docs(service): clarify ACL setup requirements for service and interactive user access

.gitignore

@@ -3,4 +3,4 @@ scripts/__pycache__/
 .DS_Store
 .cargo/config.toml
 .vscode/
-docs/superpowers
+docs/

.woodpecker/server-test.yaml

@@ -24,4 +24,4 @@ steps:
       - mise install rust 
       - mise install protoc
       - mise install cargo:cargo-nextest
-      - mise exec cargo:cargo-nextest -- cargo nextest run --no-fail-fast --all-features
+      - mise exec cargo:cargo-nextest -- cargo nextest run --no-fail-fast

AGENTS.md

@@ -6,7 +6,7 @@ This file provides guidance to Codex (Codex.ai/code) when working with code in t
 
 Arbiter is a **permissioned signing service** for cryptocurrency wallets. It consists of:
 - **`server/`** — Rust gRPC daemon that holds encrypted keys and enforces policies
-- **`operator/`** — Flutter desktop app (macOS/Windows) with a Rust backend via Rinf
+- **`useragent/`** — Flutter desktop app (macOS/Windows) with a Rust backend via Rinf
 - **`protobufs/`** — Protocol Buffer definitions shared between server and client
 
 The vault never exposes key material; it only produces signatures when requests satisfy configured policies.
@@ -28,7 +28,7 @@ Key versions: Rust 1.93.0 (with clippy), Flutter 3.38.9-stable, protoc 29.6, die
 |---|---|
 | `arbiter-proto` | Generated gRPC stubs + protobuf types; compiled from `protobufs/*.proto` via `tonic-prost-build` |
 | `arbiter-server` | Main daemon — actors, DB, EVM policy engine, gRPC service implementation |
-| `arbiter-operator` | Rust client library for the operator side of the gRPC protocol |
+| `arbiter-useragent` | Rust client library for the user agent side of the gRPC protocol |
 | `arbiter-client` | Rust client library for SDK clients |
 
 ### Common Commands
@@ -66,11 +66,11 @@ cargo insta review
 The server is actor-based using the **kameo** crate. All long-lived state lives in `GlobalActors`:
 
 - **`Bootstrapper`** — Manages the one-time bootstrap token written to `~/.arbiter/bootstrap_token` on first run.
-- **`Vault`** — Holds the encrypted root key and manages the Sealed/Unsealed vault state machine. On unseal, decrypts the root key into a `memsafe` hardened memory cell.
+- **`KeyHolder`** — Holds the encrypted root key and manages the Sealed/Unsealed vault state machine. On unseal, decrypts the root key into a `memsafe` hardened memory cell.
-- **`FlowCoordinator`** — Coordinates cross-connection flow between operators and SDK clients.
+- **`FlowCoordinator`** — Coordinates cross-connection flow between user agents and SDK clients.
 - **`EvmActor`** — Handles EVM transaction policy enforcement and signing.
 
-Per-connection actors live under `actors/operator/` and `actors/client/`, each with `auth` (challenge-response authentication) and `session` (post-auth operations) sub-modules.
+Per-connection actors live under `actors/user_agent/` and `actors/client/`, each with `auth` (challenge-response authentication) and `session` (post-auth operations) sub-modules.
 
 **Database:** SQLite via `diesel-async` + `bb8` connection pool. Schema managed by embedded Diesel migrations in `crates/arbiter-server/migrations/`. DB file lives at `~/.arbiter/arbiter.sqlite`. Tests use a temp-file DB via `db::create_test_pool()`.
 
@@ -100,41 +100,20 @@ diesel migration generate <name> --migration-dir crates/arbiter-server/migration
 diesel migration run --migration-dir crates/arbiter-server/migrations
 ```
 
-### Code Conventions
+## User Agent (Flutter + Rinf at `useragent/`)
 
-**`#[must_use]` Attribute:**
+The Flutter app uses [Rinf](https://rinf.cunarist.org) to call Rust code. The Rust logic lives in `useragent/native/hub/` as a separate crate that uses `arbiter-useragent` for the gRPC client.
-Apply the `#[must_use]` attribute to return types of functions where the return value is critical and should not be accidentally ignored. This is commonly used for:
 
-- Methods that return `bool` indicating success/failure or validation state
+Communication between Dart and Rust uses typed **signals** defined in `useragent/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
-- Any function where ignoring the return value indicates a logic error
-
-Do not apply `#[must_use]` redundantly to items (types or functions) that are already annotated with `#[must_use]`.
-
-Example:
-
-```rust
-#[must_use]
-pub fn verify(&self, nonce: i32, context: &[u8], signature: &Signature) -> bool {
-    // verification logic
-}
-```
-
-This forces callers to either use the return value or explicitly ignore it with `let _ = ...;`, preventing silent failures.
-
-## Operator (Flutter + Rinf at `operator/`)
-
-The Flutter app uses [Rinf](https://rinf.cunarist.org) to call Rust code. The Rust logic lives in `operator/native/hub/` as a separate crate that uses `arbiter-operator` for the gRPC client.
-
-Communication between Dart and Rust uses typed **signals** defined in `operator/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
 
 ```sh
-cd operator && rinf gen
+cd useragent && rinf gen
 ```
 
 ### Common Commands
 
 ```sh
-cd operator
+cd useragent
 
 # Run the app (macOS or Windows)
 flutter run
@@ -146,4 +125,4 @@ rinf gen
 flutter analyze
 ```
 
-The Rinf Rust entry point is `operator/native/hub/src/lib.rs`. It spawns actors defined in `operator/native/hub/src/actors/` which handle Dart↔server communication via signals.
+The Rinf Rust entry point is `useragent/native/hub/src/lib.rs`. It spawns actors defined in `useragent/native/hub/src/actors/` which handle Dart↔server communication via signals.

ARCHITECTURE.md

@@ -0,0 +1,155 @@
+# Arbiter
+
+Arbiter is a permissioned signing service for cryptocurrency wallets. It runs as a background service on the user's machine with an optional client application for vault management.
+
+**Core principle:** The vault NEVER exposes key material. It only produces signatures when a request satisfies the configured policies.
+---
+
+## 1. Peer Types
+
+Arbiter distinguishes two kinds of peers:
+
+- **User Agent** — A client application used by the owner to manage the vault (create wallets, approve SDK clients, configure policies).
+- **SDK Client** — A consumer of signing capabilities, typically an automation tool. In the future, this could include a browser-based wallet.
+
+---
+
+## 2. Authentication
+
+### 2.1 Challenge-Response
+
+All peers authenticate via public-key cryptography using a challenge-response protocol:
+
+1. The peer sends its public key and requests a challenge.
+2. The server looks up the key in its database. If found, it increments the nonce and returns a challenge (replay-attack protection).
+3. The peer signs the challenge with its private key and sends the signature back.
+4. The server verifies the signature:
+   - **Pass:** The connection is considered authenticated.
+   - **Fail:** The server closes the connection.
+
+### 2.2 User Agent Bootstrap
+
+On first run — when no User Agents are registered — the server generates a one-time bootstrap token. It is made available in two ways:
+
+- **Local setup:** Written to `~/.arbiter/bootstrap_token` for automatic discovery by a co-located User Agent.
+- **Remote setup:** Printed to the server's console output.
+
+The first User Agent must present this token alongside the standard challenge-response to complete registration.
+
+### 2.3 SDK Client Registration
+
+There is no bootstrap mechanism for SDK clients. They must be explicitly approved by an already-registered User Agent.
+
+---
+
+## 3. Server Identity
+
+The server proves its identity using TLS with a self-signed certificate. The TLS private key is generated on first run and is long-term; no rotation mechanism exists yet due to the complexity of multi-peer coordination.
+
+Peers verify the server by its **public key fingerprint**:
+
+- **User Agent (local):** Receives the fingerprint automatically through the bootstrap token.
+- **User Agent (remote) / SDK Client:** Must receive the fingerprint out-of-band.
+
+> A streamlined setup mechanism using a single connection string is planned but not yet implemented.
+
+---
+
+## 4. Key Management
+
+### 4.1 Key Hierarchy
+
+There are three layers of keys:
+
+| Key | Encrypts | Encrypted by |
+|---|---|---|
+| **User key** (password) | Root key | — (derived from user input) |
+| **Root key** | Wallet keys | User key |
+| **Wallet keys** | — (used for signing) | Root key |
+
+This layered design enables:
+
+- **Password rotation** without re-encrypting every wallet key (only the root key is re-encrypted).
+- **Root key rotation** without requiring the user to change their password.
+
+### 4.2 Encryption at Rest
+
+The database stores everything in encrypted form using symmetric AEAD. The encryption scheme is versioned to support transparent migration — when the vault unseals, Arbiter automatically re-encrypts any entries that are behind the current scheme version. See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the specific scheme and versioning mechanism.
+
+---
+
+## 5. Vault Lifecycle
+
+### 5.1 Sealed State
+
+On boot, the root key is encrypted and the server cannot perform any signing operations. This state is called **Sealed**.
+
+### 5.2 Unseal Flow
+
+To transition to the **Unsealed** state, a User Agent must provide the password:
+
+1. The User Agent initiates an unseal request.
+2. The server generates a one-time key pair and returns the public key.
+3. The User Agent encrypts the user's password with this one-time public key and sends the ciphertext to the server.
+4. The server decrypts and verifies the password:
+   - **Success:** The root key is decrypted and placed into a hardened memory cell. The server transitions to `Unsealed`. Any entries pending encryption scheme migration are re-encrypted.
+   - **Failure:** The server returns an error indicating the password is incorrect.
+
+### 5.3 Memory Protection
+
+Once unsealed, the root key must be protected in memory against:
+
+- Memory dumps
+- Page swaps to disk
+- Hibernation files
+
+See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the current and planned memory protection approaches.
+
+---
+
+## 6. Permission Engine
+
+### 6.1 Fundamental Rules
+
+- SDK clients have **no access by default**.
+- Access is granted **explicitly** by a User Agent.
+- Grants are scoped to **specific wallets** and governed by **policies**.
+
+Each blockchain requires its own policy system due to differences in static transaction analysis. Currently, only EVM is supported; Solana support is planned.
+
+Arbiter is also responsible for ensuring that **transaction nonces are never reused**.
+
+### 6.2 EVM Policies
+
+Every EVM grant is scoped to a specific **wallet** and **chain ID**.
+
+#### 6.2.1 Transaction Sub-Grants
+
+Arbiter maintains an ever-expanding database of known contracts and their ABIs. Based on contract knowledge, transaction requests fall into three categories:
+
+**1. Known contract (ABI available)**
+
+The transaction can be decoded and presented with semantic meaning. For example: *"Client X wants to transfer Y USDT to address Z."*
+
+Available restrictions:
+- Volume limits (e.g., "no more than 10,000 tokens ever")
+- Rate limits (e.g., "no more than 100 tokens per hour")
+
+**2. Unknown contract (no ABI)**
+
+The transaction cannot be decoded, so its effects are opaque — it could do anything, including draining all tokens. The user is warned, and if approved, access is granted to all interactions with the contract (matched by the `to` field).
+
+Available restrictions:
+- Transaction count limits (e.g., "no more than 100 transactions ever")
+- Rate limits (e.g., "no more than 5 transactions per hour")
+
+**3. Plain ether transfer (no calldata)**
+
+These transactions have no `calldata` and therefore cannot interact with contracts. They can be subject to the same volume and rate restrictions as above.
+
+#### 6.2.2 Global Limits
+
+In addition to sub-grant-specific restrictions, the following limits can be applied across all grant types:
+
+- **Gas limit** — Maximum gas per transaction.
+- **Time-window restrictions** — e.g., signing allowed only 08:00–20:00 on Mondays and Thursdays.

CLAUDE.md

@@ -1 +1,128 @@
-Refer to @AGENTS.md for instructions.
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+Arbiter is a **permissioned signing service** for cryptocurrency wallets. It consists of:
+- **`server/`** — Rust gRPC daemon that holds encrypted keys and enforces policies
+- **`useragent/`** — Flutter desktop app (macOS/Windows) with a Rust backend via Rinf
+- **`protobufs/`** — Protocol Buffer definitions shared between server and client
+
+The vault never exposes key material; it only produces signatures when requests satisfy configured policies.
+
+## Toolchain Setup
+
+Tools are managed via [mise](https://mise.jdx.dev/). Install all required tools:
+```sh
+mise install
+```
+
+Key versions: Rust 1.93.0 (with clippy), Flutter 3.38.9-stable, protoc 29.6, diesel_cli 2.3.6 (sqlite).
+
+## Server (Rust workspace at `server/`)
+
+### Crates
+
+| Crate | Purpose |
+|---|---|
+| `arbiter-proto` | Generated gRPC stubs + protobuf types; compiled from `protobufs/*.proto` via `tonic-prost-build` |
+| `arbiter-server` | Main daemon — actors, DB, EVM policy engine, gRPC service implementation |
+| `arbiter-useragent` | Rust client library for the user agent side of the gRPC protocol |
+| `arbiter-client` | Rust client library for SDK clients |
+
+### Common Commands
+
+```sh
+cd server
+
+# Build
+cargo build
+
+# Run the server daemon
+cargo run -p arbiter-server
+
+# Run all tests (preferred over cargo test)
+cargo nextest run
+
+# Run a single test
+cargo nextest run <test_name>
+
+# Lint
+cargo clippy
+
+# Security audit
+cargo audit
+
+# Check unused dependencies
+cargo shear
+
+# Run snapshot tests and update snapshots
+cargo insta review
+```
+
+### Architecture
+
+The server is actor-based using the **kameo** crate. All long-lived state lives in `GlobalActors`:
+
+- **`Bootstrapper`** — Manages the one-time bootstrap token written to `~/.arbiter/bootstrap_token` on first run.
+- **`KeyHolder`** — Holds the encrypted root key and manages the Sealed/Unsealed vault state machine. On unseal, decrypts the root key into a `memsafe` hardened memory cell.
+- **`FlowCoordinator`** — Coordinates cross-connection flow between user agents and SDK clients.
+- **`EvmActor`** — Handles EVM transaction policy enforcement and signing.
+
+Per-connection actors live under `actors/user_agent/` and `actors/client/`, each with `auth` (challenge-response authentication) and `session` (post-auth operations) sub-modules.
+
+**Database:** SQLite via `diesel-async` + `bb8` connection pool. Schema managed by embedded Diesel migrations in `crates/arbiter-server/migrations/`. DB file lives at `~/.arbiter/arbiter.sqlite`. Tests use a temp-file DB via `db::create_test_pool()`.
+
+**Cryptography:**
+- Authentication: ed25519 (challenge-response, nonce-tracked per peer)
+- Encryption at rest: XChaCha20-Poly1305 (versioned via `scheme` field for transparent migration on unseal)
+- Password KDF: Argon2
+- Unseal transport: X25519 ephemeral key exchange
+- TLS: self-signed certificate (aws-lc-rs backend), fingerprint distributed via `ArbiterUrl`
+
+**Protocol:** gRPC with Protocol Buffers. The `ArbiterUrl` type encodes host, port, CA cert, and bootstrap token into a single shareable string (printed to console on first run).
+
+### Proto Regeneration
+
+When `.proto` files in `protobufs/` change, rebuild to regenerate:
+```sh
+cd server && cargo build -p arbiter-proto
+```
+
+### Database Migrations
+
+```sh
+# Create a new migration
+diesel migration generate <name> --migration-dir crates/arbiter-server/migrations
+
+# Run migrations manually (server also runs them on startup)
+diesel migration run --migration-dir crates/arbiter-server/migrations
+```
+
+## User Agent (Flutter + Rinf at `useragent/`)
+
+The Flutter app uses [Rinf](https://rinf.cunarist.org) to call Rust code. The Rust logic lives in `useragent/native/hub/` as a separate crate that uses `arbiter-useragent` for the gRPC client.
+
+Communication between Dart and Rust uses typed **signals** defined in `useragent/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
+
+```sh
+cd useragent && rinf gen
+```
+
+### Common Commands
+
+```sh
+cd useragent
+
+# Run the app (macOS or Windows)
+flutter run
+
+# Regenerate Rust↔Dart signal bindings
+rinf gen
+
+# Analyze Dart code
+flutter analyze
+```
+
+The Rinf Rust entry point is `useragent/native/hub/src/lib.rs`. It spawns actors defined in `useragent/native/hub/src/actors/` which handle Dart↔server communication via signals.

IMPLEMENTATION.md

@@ -8,10 +8,10 @@ This document covers concrete technology choices and dependencies. For the archi
 
 ### Authentication Result Semantics
 
-Authentication no longer uses an implicit success-only response shape. Both `client` and `operator` return explicit auth status enums over the wire.
+Authentication no longer uses an implicit success-only response shape. Both `client` and `user-agent` return explicit auth status enums over the wire.
 
-- **Client:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `APPROVAL_DENIED`, `NO_OPERATORS_ONLINE`, or `INTERNAL`
+- **Client:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `APPROVAL_DENIED`, `NO_USER_AGENTS_ONLINE`, or `INTERNAL`
-- **Operator:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `BOOTSTRAP_REQUIRED`, `TOKEN_INVALID`, or `INTERNAL`
+- **User-agent:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `BOOTSTRAP_REQUIRED`, `TOKEN_INVALID`, or `INTERNAL`
 
 This makes transport-level failures and actor/domain-level auth failures distinct:
 
@@ -22,50 +22,52 @@ Clients are expected to handle these status codes directly and present the concr
 
 ### New Client Approval
 
-When a client whose public key is not yet in the database connects, all connected operators are asked to approve the connection. The first operator to respond determines the outcome; remaining requests are cancelled via a watch channel.
+When a client whose public key is not yet in the database connects, all connected user agents are asked to approve the connection. The first agent to respond determines the outcome; remaining requests are cancelled via a watch channel.
 
 ```mermaid
 flowchart TD
     A([Client connects]) --> B[Receive AuthChallengeRequest]
     B --> C{pubkey in DB?}
 
-    C -- yes --> G[Generate AuthChallenge]
+    C -- yes --> D[Read nonce\nIncrement nonce in DB]
+    D --> G
 
-    C -- no --> E[Ask all Operators:\nClientConnectionRequest]
+    C -- no --> E[Ask all UserAgents:\nClientConnectionRequest]
     E --> F{First response}
     F -- denied --> Z([Reject connection])
-    F -- approved --> F2[Cancel remaining\nOperator requests]
+    F -- approved --> F2[Cancel remaining\nUserAgent requests]
-    F2 --> F3[INSERT client]
+    F2 --> F3[INSERT client\nnonce = 1]
-    F3 --> G
+    F3 --> G[Send AuthChallenge\nwith nonce]
 
-    G --> H[Send AuthChallenge\ntimestamp + random bytes]
+    G --> H[Receive AuthChallengeSolution]
-    H --> I[Receive AuthChallengeSolution]
+    H --> I{Signature valid?}
-    I --> K{Signature valid?}
+    I -- no --> Z
-    K -- no --> Z
+    I -- yes --> J([Session started])
-    K -- yes --> J([Session started])
 ```
 
-Auth challenges are generated from fresh random bytes plus a nanosecond timestamp. The server keeps the issued challenge only in the in-flight authentication state for that connection, then verifies the signature against the same canonical challenge payload.
+### Known Issue: Concurrent Registration Race (TOCTOU)
 
-The authentication schema stores peer identity, not replay counters:
+Two connections presenting the same previously-unknown public key can race through the approval flow simultaneously:
 
-- `program_client` stores the SDK client's public key, metadata binding, and timestamps.
+1. Both check the DB → neither is registered.
-- `operator_client` stores the Operator public key and timestamps.
+2. Both request approval from user agents → both receive approval.
-- Neither table stores an authentication nonce, and challenge generation does not update either table.
+3. Both `INSERT` the client record → the second insert silently overwrites the first, resetting the nonce.
+
+This means the first connection's nonce is invalidated by the second, causing its challenge verification to fail. A fix requires either serialising new-client registration (e.g. an in-memory lock keyed on pubkey) or replacing the separate check + insert with an `INSERT OR IGNORE` / upsert guarded by a unique constraint on `public_key`.
+
+### Nonce Semantics
+
+The `program_client.nonce` column stores the **next usable nonce** — i.e. it is always one ahead of the nonce last issued in a challenge.
+
+- **New client:** inserted with `nonce = 1`; the first challenge is issued with `nonce = 0`.
+- **Existing client:** the current DB value is read and used as the challenge nonce, then immediately incremented within the same exclusive transaction, preventing replay.
 
 ---
 
 ## Cryptography
 
 ### Authentication
-- **Client protocol:** ML-DSA
+- **Signature scheme:** ed25519
-
-### User-Agent Authentication
-
-Operator authentication supports multiple signature schemes because platform-provided "hardware-bound" keys do not expose a uniform algorithm across operating systems and hardware.
-
-- **Supported schemes:** ML-DSA
-- **Why:** Secure Enclave (MacOS) support them natively, on other platforms we could emulate while they roll-out
 
 ### Encryption at Rest
 - **Scheme:** Symmetric AEAD — currently **XChaCha20-Poly1305**
@@ -86,7 +88,7 @@ Operator authentication supports multiple signature schemes because platform-pro
 
 ### Request Multiplexing
 
-Both `client` and `operator` connections support multiple in-flight requests over one gRPC bidi stream.
+Both `client` and `user-agent` connections support multiple in-flight requests over one gRPC bidi stream.
 
 - Every request carries a monotonically increasing request ID
 - Every normal response echoes the request ID it corresponds to
@@ -115,52 +117,6 @@ The central abstraction is the `Policy` trait. Each implementation handles one s
 4. **Evaluate** — `Policy::evaluate` checks the decoded meaning against the grant's policy-specific constraints and returns any violations.
 5. **Record** — If `RunKind::Execution` and there are no violations, the engine writes to `evm_transaction_log` and calls `Policy::record_transaction` for any policy-specific logging (e.g., token transfer volume).
 
-The detailed branch structure is shown below:
-
-```mermaid
-flowchart TD
-    A[SDK Client sends sign transaction request] --> B[Server resolves wallet]
-    B --> C{Wallet exists?}
-
-    C -- No --> Z1[Return wallet not found error]
-    C -- Yes --> D[Check SDK client wallet visibility]
-
-    D --> E{Wallet visible to SDK client?}
-    E -- No --> F[Start wallet visibility voting flow]
-    F --> G{Vote approved?}
-    G -- No --> Z2[Return wallet access denied error]
-    G -- Yes --> H[Persist wallet visibility]
-    E -- Yes --> I[Classify transaction meaning]
-    H --> I
-
-    I --> J{Meaning supported?}
-    J -- No --> Z3[Return unsupported transaction error]
-    J -- Yes --> K[Find matching grant]
-
-    K --> L{Grant exists?}
-    L -- Yes --> M[Check grant limits]
-    L -- No --> N[Start execution or grant voting flow]
-
-    N --> O{Operator decision}
-    O -- Reject --> Z4[Return no matching grant error]
-    O -- Allow once --> M
-    O -- Create grant --> P[Create grant with user-selected limits]
-    P --> Q[Persist grant]
-    Q --> M
-
-    M --> R{Limits exceeded?}
-    R -- Yes --> Z5[Return evaluation error]
-    R -- No --> S[Record transaction in logs]
-    S --> T[Produce signature]
-    T --> U[Return signature to SDK client]
-
-    note1[Limit checks include volume, count, and gas constraints.]
-    note2[Grant lookup depends on classified meaning, such as ether transfer or token transfer.]
-
-    K -. uses .-> note2
-    M -. checks .-> note1
-```
-
 ### Policy Trait
 
 | Method | Purpose |
@@ -192,7 +148,7 @@ flowchart TD
 Every grant has two layers:
 
 - **Shared (`evm_basic_grant`)** — wallet, chain, validity period, gas fee caps, transaction count rate limit. One row per grant regardless of type.
-- **Specific** — policy-owned tables (`evm_ether_transfer_grant`, `evm_token_transfer_grant`) holding type-specific configuration.
+- **Specific** — policy-owned tables (`evm_ether_transfer_grant`, `evm_token_transfer_grant`, etc.) holding type-specific configuration.
 
 `find_all_grants` uses a `#[diesel::auto_type]` base join between the specific and shared tables, then batch-loads related rows (targets, volume limits) in two additional queries to avoid N+1.
 
@@ -215,6 +171,7 @@ These are checked centrally in `check_shared_constraints` before policy evaluati
 - **Only EIP-1559 transactions are supported.** Legacy and EIP-2930 types are rejected outright.
 - **No opaque-calldata (unknown contract) grant type.** The architecture describes a category for unrecognised contracts, but no policy implements it yet. Any transaction that is not a plain ETH transfer or a known ERC-20 transfer is unconditionally rejected.
 - **Token registry is static.** Tokens are recognised only if they appear in the hard-coded `arbiter_tokens_registry` crate. There is no mechanism to register additional contracts at runtime.
+- **Nonce management is not implemented.** The architecture lists nonce deduplication as a core responsibility, but no nonce tracking or enforcement exists yet.
 
 ---
 
@@ -222,5 +179,5 @@ These are checked centrally in `check_shared_constraints` before policy evaluati
 
 The unsealed root key must be held in a hardened memory cell resistant to dumps, page swaps, and hibernation.
 
-- **Current:** A dedicated memory-protection abstraction is in place, with `memsafe` used behind that abstraction today
+- **Current:** Using the `memsafe` crate as an interim solution
-- **Planned:** Additional backends can be introduced behind the same abstraction, including a custom implementation based on `mlock` (Unix) and `VirtualProtect` (Windows)
+- **Planned:** Custom implementation based on `mlock` (Unix) and `VirtualProtect` (Windows)

README.md

@@ -4,7 +4,7 @@
 ## Security warning
 Arbiter can't meaningfully protect against host compromise. Potential attack flow:
 - Attacker steals TLS keys from database
-- Pretends to be server; just accepts operator challenge solutions
+- Pretends to be server; just accepts user agent challenge solutions
 - Pretend to be in sealed state and performing DH with client
 - Steals user password and derives seal key
 

docs/ARCHITECTURE.md

@@ -1,334 +0,0 @@
-# Arbiter
-
-Arbiter is a permissioned signing service for cryptocurrency wallets. It runs as a background service on the user's machine with an optional client application for vault management.
-
-**Core principle:** The vault NEVER exposes key material. It only produces signatures when a request satisfies the configured policies.
----
-
-## 1. Peer Types
-
-Arbiter distinguishes two kinds of peers:
-
-- **Operator** — A client application used by the owner to manage the vault (create wallets, approve SDK clients, configure policies).
-- **SDK Client** — A consumer of signing capabilities, typically an automation tool. In the future, this could include a browser-based wallet.
-- **Recovery Operator** — A dormant recovery participant with narrowly scoped authority used only for custody recovery and operator replacement.
-
----
-
-## 2. Authentication
-
-### 2.1 Challenge-Response
-
-All peers authenticate via public-key cryptography using a challenge-response protocol:
-
-1. The peer sends its public key and requests a challenge.
-2. The server looks up the key in its database. If found, it generates a fresh challenge from random bytes plus the current timestamp.
-3. The peer signs the canonical challenge payload with its private key and sends the signature back.
-4. The server verifies the signature:
-   - **Pass:** The connection is considered authenticated.
-   - **Fail:** The server closes the connection.
-
-Authentication challenges are per-connection, ephemeral values. They are not persisted in the peer tables, and peer records store no challenge state.
-
-### 2.2 Operator Bootstrap
-
-On first run — when no Operators are registered — the server generates a one-time bootstrap token. It is made available in two ways:
-
-- **Local setup:** Written to `~/.arbiter/bootstrap_token` for automatic discovery by a co-located Operator.
-- **Remote setup:** Printed to the server's console output.
-
-The first Operator must present this token alongside the standard challenge-response to complete registration.
-
-### 2.3 SDK Client Registration
-
-There is no bootstrap mechanism for SDK clients. They must be explicitly approved by an already-registered Operator.
-
----
-
-## 3. Multi-Operator Governance
-
-When more than one Operator is registered, the vault is treated as having multiple operators. In that mode, sensitive actions are governed by voting rather than by a single operator decision.
-
-### 3.1 Voting Rules
-
-Voting is based on the total number of registered operators:
-
-- **1 operator:** no vote is needed; the single operator decides directly.
-- **2 operators:** full consensus is required; both operators must approve.
-- **3 or more operators:** quorum is `floor(N / 2) + 1`.
-
-For a decision to count, the operator's approval or rejection must be signed by that operator's associated key. Unsigned votes, or votes that fail signature verification, are ignored.
-
-Examples:
-
-- **3 operators:** 2 approvals required
-- **4 operators:** 3 approvals required
-
-### 3.2 Actions Requiring a Vote
-
-In multi-operator mode, a successful vote is required for:
-
-- approving new SDK clients
-- granting an SDK client visibility to a wallet
-- approving a one-off transaction
-- approving creation of a persistent grant
-- approving operator replacement
-- approving server updates
-- updating Shamir secret-sharing parameters
-
-### 3.3 Special Rule for Key Rotation
-
-Key rotation always requires full quorum, regardless of the normal voting threshold.
-
-This is stricter than ordinary governance actions because rotating the root key requires every operator to participate in coordinated share refresh/update steps. The root key itself is not redistributed directly, but each operator's share material must be changed consistently.
-
-### 3.4 Root Key Custody
-
-When the vault has multiple operators, the vault root key is protected using Shamir secret sharing.
-
-The vault root key is encrypted in a way that requires reconstruction from user-held shares rather than from a single shared password.
-
-For ordinary operators, the Shamir threshold matches the ordinary governance quorum. For example:
-
-- **2 operators:** `2-of-2`
-- **3 operators:** `2-of-3`
-- **4 operators:** `3-of-4`
-
-In practice, the Shamir share set also includes Recovery Operator shares. This means the effective Shamir parameters are computed over the combined share pool while keeping the same threshold. For example:
-
-- **3 ordinary operators + 2 recovery shares:** `2-of-5`
-
-This ensures that the normal custody threshold follows the ordinary operator quorum, while still allowing dormant recovery shares to exist for break-glass recovery flows.
-
-### 3.5 Recovery Operators
-
-Recovery Operators are a separate peer type from ordinary vault operators.
-
-Their role is intentionally narrow. They can only:
-
-- participate in unsealing the vault
-- vote for operator replacement
-
-Recovery Operators do not participate in routine governance such as approving SDK clients, granting wallet visibility, approving transactions, creating grants, approving server updates, or changing Shamir parameters.
-
-### 3.6 Sleeping and Waking Recovery Operators
-
-By default, Recovery Operators are **sleeping** and do not participate in any active flow.
-
-Any ordinary operator may request that Recovery Operators **wake up**.
-
-Any ordinary operator may also cancel a pending wake-up request.
-
-This creates a dispute window before recovery powers become active. The default wake-up delay is **14 days**.
-
-Recovery Operators are therefore part of the break-glass recovery path rather than the normal operating quorum.
-
-The high-level recovery flow is:
-
-```mermaid
-sequenceDiagram
-    autonumber
-    actor Op as Ordinary Operator
-    participant Server
-    actor Other as Other Operator
-    actor Rec as Recovery Operator
-
-    Op->>Server: Request recovery wake-up
-    Server-->>Op: Wake-up pending
-    Note over Server: Default dispute window: 14 days
-
-    alt Wake-up cancelled during dispute window
-        Other->>Server: Cancel wake-up
-        Server-->>Op: Recovery cancelled
-        Server-->>Rec: Stay sleeping
-    else No cancellation for 14 days
-        Server-->>Rec: Wake up
-        Rec->>Server: Join recovery flow
-        critical Recovery authority
-            Rec->>Server: Participate in unseal
-            Rec->>Server: Vote on operator replacement
-        end
-        Server-->>Op: Recovery mode active
-    end
-```
-
-### 3.7 Committee Formation
-
-There are two ways to form a multi-operator committee:
-
-- convert an existing single-operator vault by adding new operators
-- bootstrap an unbootstrapped vault directly into multi-operator mode
-
-In both cases, committee formation is a coordinated process. Arbiter does not allow multi-operator custody to emerge implicitly from unrelated registrations.
-
-### 3.8 Bootstrapping an Unbootstrapped Vault into Multi-Operator Mode
-
-When an unbootstrapped vault is initialized as a multi-operator vault, the setup proceeds as follows:
-
-1. An operator connects to the unbootstrapped vault using an Operator and the bootstrap token.
-2. During bootstrap setup, that operator declares:
-   - the total number of ordinary operators
-   - the total number of Recovery Operators
-3. The vault enters **multi-bootstrap mode**.
-4. While in multi-bootstrap mode:
-   - every ordinary operator must connect with an Operator using the bootstrap token
-   - every Recovery Operator must also connect using the bootstrap token
-   - each participant is registered individually
-   - each participant's share is created and protected with that participant's credentials
-5. The vault is considered fully bootstrapped only after all declared operator and recovery-share registrations have completed successfully.
-
-This means the operator and recovery set is fixed at bootstrap completion time, based on the counts declared when multi-bootstrap mode was entered.
-
-### 3.9 Special Bootstrap Constraint for Two-Operator Vaults
-
-If a vault is declared with exactly **2 ordinary operators**, Arbiter requires at least **1 Recovery Operator** to be configured during bootstrap.
-
-This prevents the worst-case custody failure in which a `2-of-2` operator set becomes permanently unrecoverable after loss of a single operator.
-
----
-
-## 4. Server Identity
-
-The server proves its identity using TLS with a self-signed certificate. The TLS private key is generated on first run and is long-term; no rotation mechanism exists yet due to the complexity of multi-peer coordination.
-
-Peers verify the server by its **public key fingerprint**:
-
-- **Operator (local):** Receives the fingerprint automatically through the bootstrap token.
-- **Operator (remote) / SDK Client:** Must receive the fingerprint out-of-band.
-
-> A streamlined setup mechanism using a single connection string is planned but not yet implemented.
-
----
-
-## 5. Key Management
-
-### 5.1 Key Hierarchy
-
-There are three layers of keys:
-
-| Key | Encrypts | Encrypted by |
-|---|---|---|
-| **User key** (password) | Root key | — (derived from user input) |
-| **Root key** | Wallet keys | User key |
-| **Wallet keys** | — (used for signing) | Root key |
-
-This layered design enables:
-
-- **Password rotation** without re-encrypting every wallet key (only the root key is re-encrypted).
-- **Root key rotation** without requiring the user to change their password.
-
-### 5.2 Encryption at Rest
-
-The database stores everything in encrypted form using symmetric AEAD. The encryption scheme is versioned to support transparent migration — when the vault unseals, Arbiter automatically re-encrypts any entries that are behind the current scheme version. See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the specific scheme and versioning mechanism.
-
----
-
-## 6. Vault Lifecycle
-
-### 6.1 Sealed State
-
-On boot, the root key is encrypted and the server cannot perform any signing operations. This state is called **Sealed**.
-
-### 6.2 Unseal Flow
-
-To transition to the **Unsealed** state, an Operator must provide the password:
-
-1. The Operator initiates an unseal request.
-2. The server generates a one-time key pair and returns the public key.
-3. The Operator encrypts the user's password with this one-time public key and sends the ciphertext to the server.
-4. The server decrypts and verifies the password:
-   - **Success:** The root key is decrypted and placed into a hardened memory cell. The server transitions to `Unsealed`. Any entries pending encryption scheme migration are re-encrypted.
-   - **Failure:** The server returns an error indicating the password is incorrect.
-
-### 6.3 Memory Protection
-
-Once unsealed, the root key must be protected in memory against:
-
-- Memory dumps
-- Page swaps to disk
-- Hibernation files
-
-See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the current and planned memory protection approaches.
-
----
-
-## 7. Permission Engine
-
-### 7.1 Fundamental Rules
-
-- SDK clients have **no access by default**.
-- Access is granted **explicitly** by an Operator.
-- Grants are scoped to **specific wallets** and governed by **policies**.
-
-Each blockchain requires its own policy system due to differences in static transaction analysis. Currently, only EVM is supported; Solana support is planned.
-
-Arbiter is also responsible for ensuring that **transaction nonces are never reused**.
-
-### 7.2 EVM Policies
-
-Every EVM grant is scoped to a specific **wallet** and **chain ID**.
-
-#### 7.2.0 Transaction Signing Sequence
-
-The high-level interaction order is:
-
-```mermaid
-sequenceDiagram
-    autonumber
-    actor SDK as SDK Client
-    participant Server
-    participant operator as Operator
-
-    SDK->>Server: SignTransactionRequest
-    Server->>Server: Resolve wallet and wallet visibility
-    alt Visibility approval required
-        Server->>operator: Ask for wallet visibility approval
-        operator-->>Server: Vote result
-    end
-    Server->>Server: Evaluate transaction
-    Server->>Server: Load grant and limits context
-    alt Grant approval required
-        Server->>operator: Ask for execution / grant approval
-        operator-->>Server: Vote result
-        opt Create persistent grant
-            Server->>Server: Create and store grant
-        end
-        Server->>Server: Retry evaluation
-    end
-    critical Final authorization path
-        Server->>Server: Check limits and record execution
-        Server-->>Server: Signature or evaluation error
-    end
-    Server-->>SDK: Signature or error
-```
-
-#### 7.2.1 Transaction Sub-Grants
-
-Arbiter maintains an ever-expanding database of known contracts and their ABIs. Based on contract knowledge, transaction requests fall into three categories:
-
-**1. Known contract (ABI available)**
-
-The transaction can be decoded and presented with semantic meaning. For example: *"Client X wants to transfer Y USDT to address Z."*
-
-Available restrictions:
-- Volume limits (e.g., "no more than 10,000 tokens ever")
-- Rate limits (e.g., "no more than 100 tokens per hour")
-
-**2. Unknown contract (no ABI)**
-
-The transaction cannot be decoded, so its effects are opaque — it could do anything, including draining all tokens. The user is warned, and if approved, access is granted to all interactions with the contract (matched by the `to` field).
-
-Available restrictions:
-- Transaction count limits (e.g., "no more than 100 transactions ever")
-- Rate limits (e.g., "no more than 5 transactions per hour")
-
-**3. Plain ether transfer (no calldata)**
-
-These transactions have no `calldata` and therefore cannot interact with contracts. They can be subject to the same volume and rate restrictions as above.
-
-#### 7.2.2 Global Limits
-
-In addition to sub-grant-specific restrictions, the following limits can be applied across all grant types:
-
-- **Gas limit** — Maximum gas per transaction.
-- **Time-window restrictions** — e.g., signing allowed only 08:00–20:00 on Mondays and Thursdays.

docs/superpowers/plans/2026-03-28-grant-creation-refactor.md

@@ -111,7 +111,7 @@ String shortAddress(List<int> bytes) {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/utils.dart
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/utils.dart
 ```
 
 Expected: no errors.
@@ -168,7 +168,7 @@ class GrantCreation extends _$GrantCreation {
 - [ ] **Step 2: Run code generator**
 
 ```sh
-cd operator && dart run build_runner build --delete-conflicting-outputs
+cd useragent && dart run build_runner build --delete-conflicting-outputs
 ```
 
 Expected: generates `provider.freezed.dart` and `provider.g.dart`, no errors.
@@ -176,7 +176,7 @@ Expected: generates `provider.freezed.dart` and `provider.g.dart`, no errors.
 - [ ] **Step 3: Verify**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/provider.dart
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/provider.dart
 ```
 
 Expected: no errors.
@@ -204,7 +204,7 @@ jj describe -m "feat(grants): add GrantCreation provider (client selection + gra
 
 ```dart
 // lib/screens/dashboard/evm/grants/create/fields/client_picker_field.dart
-import 'package:arbiter/proto/operator.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
 import 'package:arbiter/providers/sdk_clients/list.dart';
 import 'package:arbiter/screens/dashboard/evm/grants/create/provider.dart';
 import 'package:flutter/material.dart';
@@ -246,7 +246,7 @@ class ClientPickerField extends ConsumerWidget {
 ```dart
 // lib/screens/dashboard/evm/grants/create/fields/wallet_access_picker_field.dart
 import 'package:arbiter/proto/evm.pb.dart';
-import 'package:arbiter/proto/operator.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
 import 'package:arbiter/providers/evm/evm.dart';
 import 'package:arbiter/providers/sdk_clients/wallet_access_list.dart';
 import 'package:arbiter/screens/dashboard/evm/grants/create/provider.dart';
@@ -522,7 +522,7 @@ class TransactionRateLimitField extends StatelessWidget {
 - [ ] **Step 8: Verify all field widgets**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/fields/
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/fields/
 ```
 
 Expected: no errors.
@@ -585,7 +585,7 @@ class SharedGrantFields extends StatelessWidget {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/shared_grant_fields.dart
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/shared_grant_fields.dart
 ```
 
 Expected: no errors.
@@ -978,7 +978,7 @@ class _TokenVolumeLimitRow extends HookWidget {
 - [ ] **Step 4: Run code generator for token_transfer_grant.g.dart**
 
 ```sh
-cd operator && dart run build_runner build --delete-conflicting-outputs
+cd useragent && dart run build_runner build --delete-conflicting-outputs
 ```
 
 Expected: generates `token_transfer_grant.g.dart`, no errors.
@@ -986,7 +986,7 @@ Expected: generates `token_transfer_grant.g.dart`, no errors.
 - [ ] **Step 5: Verify**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/grants/
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/grants/
 ```
 
 Expected: no errors.
@@ -1265,7 +1265,7 @@ String _formatError(Object error) {
 - [ ] **Step 2: Verify the full create/ directory**
 
 ```sh
-cd operator && dart analyze lib/screens/dashboard/evm/grants/create/
+cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/
 ```
 
 Expected: no errors.

docs/superpowers/plans/2026-03-28-grant-grid-view.md

@@ -14,24 +14,24 @@
 
 | File | Action | Responsibility |
 |---|---|---|
-| `operator/lib/theme/palette.dart` | Modify | Add `Palette.token` (indigo accent for token-transfer cards) |
+| `useragent/lib/theme/palette.dart` | Modify | Add `Palette.token` (indigo accent for token-transfer cards) |
-| `operator/lib/features/connection/evm/wallet_access.dart` | Modify | Add `listAllWalletAccesses()` function |
+| `useragent/lib/features/connection/evm/wallet_access.dart` | Modify | Add `listAllWalletAccesses()` function |
-| `operator/lib/providers/sdk_clients/wallet_access_list.dart` | Create | `WalletAccessListProvider` — fetches full wallet access list with IDs |
+| `useragent/lib/providers/sdk_clients/wallet_access_list.dart` | Create | `WalletAccessListProvider` — fetches full wallet access list with IDs |
-| `operator/lib/screens/dashboard/evm/grants/widgets/grant_card.dart` | Create | `GrantCard` widget — watches enrichment providers + revoke mutation; one card per grant |
+| `useragent/lib/screens/dashboard/evm/grants/widgets/grant_card.dart` | Create | `GrantCard` widget — watches enrichment providers + revoke mutation; one card per grant |
-| `operator/lib/screens/dashboard/evm/grants/grants.dart` | Create | `EvmGrantsScreen` — watches `evmGrantsProvider`; handles loading/error/empty/data states; renders `GrantCard` list |
+| `useragent/lib/screens/dashboard/evm/grants/grants.dart` | Create | `EvmGrantsScreen` — watches `evmGrantsProvider`; handles loading/error/empty/data states; renders `GrantCard` list |
-| `operator/lib/router.dart` | Modify | Register `EvmGrantsRoute` in dashboard children |
+| `useragent/lib/router.dart` | Modify | Register `EvmGrantsRoute` in dashboard children |
-| `operator/lib/screens/dashboard.dart` | Modify | Add Grants entry to `routes` list and `NavigationDestination` list |
+| `useragent/lib/screens/dashboard.dart` | Modify | Add Grants entry to `routes` list and `NavigationDestination` list |
 
 ---
 
 ## Task 1: Add `Palette.token`
 
 **Files:**
-- Modify: `operator/lib/theme/palette.dart`
+- Modify: `useragent/lib/theme/palette.dart`
 
 - [ ] **Step 1: Add the color**
 
-Replace the contents of `operator/lib/theme/palette.dart` with:
+Replace the contents of `useragent/lib/theme/palette.dart` with:
 
 ```dart
 import 'package:flutter/material.dart';
@@ -48,7 +48,7 @@ class Palette {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && flutter analyze lib/theme/palette.dart
+cd useragent && flutter analyze lib/theme/palette.dart
 ```
 
 Expected: no issues.
@@ -65,20 +65,20 @@ jj new
 ## Task 2: Add `listAllWalletAccesses` feature function
 
 **Files:**
-- Modify: `operator/lib/features/connection/evm/wallet_access.dart`
+- Modify: `useragent/lib/features/connection/evm/wallet_access.dart`
 
 `readClientWalletAccess` (existing) filters the list to one client's wallet IDs and returns `Set<int>`. This new function returns the complete unfiltered list with row IDs so the grant cards can resolve wallet_access_id → wallet + client.
 
 - [ ] **Step 1: Append function**
 
-Add at the bottom of `operator/lib/features/connection/evm/wallet_access.dart`:
+Add at the bottom of `useragent/lib/features/connection/evm/wallet_access.dart`:
 
 ```dart
 Future<List<SdkClientWalletAccess>> listAllWalletAccesses(
   Connection connection,
 ) async {
   final response = await connection.ask(
-    OperatorRequest(listWalletAccess: Empty()),
+    UserAgentRequest(listWalletAccess: Empty()),
   );
   if (!response.hasListWalletAccessResponse()) {
     throw Exception(
@@ -97,7 +97,7 @@ Each returned `SdkClientWalletAccess` has:
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && flutter analyze lib/features/connection/evm/wallet_access.dart
+cd useragent && flutter analyze lib/features/connection/evm/wallet_access.dart
 ```
 
 Expected: no issues.
@@ -114,18 +114,18 @@ jj new
 ## Task 3: Create `WalletAccessListProvider`
 
 **Files:**
-- Create: `operator/lib/providers/sdk_clients/wallet_access_list.dart`
+- Create: `useragent/lib/providers/sdk_clients/wallet_access_list.dart`
-- Generated: `operator/lib/providers/sdk_clients/wallet_access_list.g.dart`
+- Generated: `useragent/lib/providers/sdk_clients/wallet_access_list.g.dart`
 
 Mirrors the structure of `EvmGrants` in `providers/evm/evm_grants.dart` — class-based `@riverpod` with a `refresh()` method.
 
 - [ ] **Step 1: Write the provider**
 
-Create `operator/lib/providers/sdk_clients/wallet_access_list.dart`:
+Create `useragent/lib/providers/sdk_clients/wallet_access_list.dart`:
 
 ```dart
 import 'package:arbiter/features/connection/evm/wallet_access.dart';
-import 'package:arbiter/proto/operator.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
 import 'package:arbiter/providers/connection/connection_manager.dart';
 import 'package:mtcore/markettakers.dart';
 import 'package:riverpod_annotation/riverpod_annotation.dart';
@@ -165,15 +165,15 @@ class WalletAccessList extends _$WalletAccessList {
 - [ ] **Step 2: Run code generation**
 
 ```sh
-cd operator && dart run build_runner build --delete-conflicting-outputs
+cd useragent && dart run build_runner build --delete-conflicting-outputs
 ```
 
-Expected: `operator/lib/providers/sdk_clients/wallet_access_list.g.dart` created. No errors.
+Expected: `useragent/lib/providers/sdk_clients/wallet_access_list.g.dart` created. No errors.
 
 - [ ] **Step 3: Verify**
 
 ```sh
-cd operator && flutter analyze lib/providers/sdk_clients/
+cd useragent && flutter analyze lib/providers/sdk_clients/
 ```
 
 Expected: no issues.
@@ -190,26 +190,26 @@ jj new
 ## Task 4: Create `GrantCard` widget
 
 **Files:**
-- Create: `operator/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`
+- Create: `useragent/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`
 
 This widget owns all per-card logic: enrichment lookups, revoke action, and rebuild scope. The screen only passes it a `GrantEntry` — the card fetches everything else itself.
 
 **Key types:**
 - `GrantEntry` (from `proto/evm.pb.dart`): `.id`, `.shared.walletAccessId`, `.shared.chainId`, `.specific.whichGrant()`
 - `SpecificGrant_Grant.etherTransfer` / `.tokenTransfer` — enum values for the oneof
-- `SdkClientWalletAccess` (from `proto/operator.pb.dart`): `.id`, `.access.walletId`, `.access.sdkClientId`
+- `SdkClientWalletAccess` (from `proto/user_agent.pb.dart`): `.id`, `.access.walletId`, `.access.sdkClientId`
 - `WalletEntry` (from `proto/evm.pb.dart`): `.id`, `.address` (List<int>)
-- `SdkClientEntry` (from `proto/operator.pb.dart`): `.id`, `.info.name`
+- `SdkClientEntry` (from `proto/user_agent.pb.dart`): `.id`, `.info.name`
 - `revokeEvmGrantMutation` — `Mutation<void>` (global; all revoke buttons disable together while any revoke is in flight)
 - `executeRevokeEvmGrant(ref, grantId: int)` — `Future<void>`
 
 - [ ] **Step 1: Write the widget**
 
-Create `operator/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`:
+Create `useragent/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`:
 
 ```dart
 import 'package:arbiter/proto/evm.pb.dart';
-import 'package:arbiter/proto/operator.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
 import 'package:arbiter/providers/evm/evm.dart';
 import 'package:arbiter/providers/evm/evm_grants.dart';
 import 'package:arbiter/providers/sdk_clients/list.dart';
@@ -438,7 +438,7 @@ class GrantCard extends ConsumerWidget {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && flutter analyze lib/screens/dashboard/evm/grants/widgets/grant_card.dart
+cd useragent && flutter analyze lib/screens/dashboard/evm/grants/widgets/grant_card.dart
 ```
 
 Expected: no issues.
@@ -455,13 +455,13 @@ jj new
 ## Task 5: Create `EvmGrantsScreen`
 
 **Files:**
-- Create: `operator/lib/screens/dashboard/evm/grants/grants.dart`
+- Create: `useragent/lib/screens/dashboard/evm/grants/grants.dart`
 
 The screen watches only `evmGrantsProvider` for top-level state (loading / error / no connection / empty / data). When there is data it renders a list of `GrantCard` widgets — each card manages its own enrichment subscriptions.
 
 - [ ] **Step 1: Write the screen**
 
-Create `operator/lib/screens/dashboard/evm/grants/grants.dart`:
+Create `useragent/lib/screens/dashboard/evm/grants/grants.dart`:
 
 ```dart
 import 'package:arbiter/proto/evm.pb.dart';
@@ -702,7 +702,7 @@ class EvmGrantsScreen extends ConsumerWidget {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd operator && flutter analyze lib/screens/dashboard/evm/grants/
+cd useragent && flutter analyze lib/screens/dashboard/evm/grants/
 ```
 
 Expected: no issues.
@@ -719,13 +719,13 @@ jj new
 ## Task 6: Wire router and dashboard tab
 
 **Files:**
-- Modify: `operator/lib/router.dart`
+- Modify: `useragent/lib/router.dart`
-- Modify: `operator/lib/screens/dashboard.dart`
+- Modify: `useragent/lib/screens/dashboard.dart`
-- Regenerated: `operator/lib/router.gr.dart`
+- Regenerated: `useragent/lib/router.gr.dart`
 
 - [ ] **Step 1: Add route to `router.dart`**
 
-Replace the contents of `operator/lib/router.dart` with:
+Replace the contents of `useragent/lib/router.dart` with:
 
 ```dart
 import 'package:auto_route/auto_route.dart';
@@ -759,7 +759,7 @@ class Router extends RootStackRouter {
 
 - [ ] **Step 2: Update `dashboard.dart`**
 
-In `operator/lib/screens/dashboard.dart`, replace the `routes` constant:
+In `useragent/lib/screens/dashboard.dart`, replace the `routes` constant:
 
 ```dart
 final routes = [
@@ -800,7 +800,7 @@ destinations: const [
 - [ ] **Step 3: Regenerate router**
 
 ```sh
-cd operator && dart run build_runner build --delete-conflicting-outputs
+cd useragent && dart run build_runner build --delete-conflicting-outputs
 ```
 
 Expected: `lib/router.gr.dart` updated, `EvmGrantsRoute` now available, no errors.
@@ -808,7 +808,7 @@ Expected: `lib/router.gr.dart` updated, `EvmGrantsRoute` now available, no error
 - [ ] **Step 4: Full project verify**
 
 ```sh
-cd operator && flutter analyze
+cd useragent && flutter analyze
 ```
 
 Expected: no issues.

docs/superpowers/specs/2026-03-28-grant-grid-view-design.md

@@ -4,7 +4,7 @@
 
 ## Overview
 
-Add a "Grants" dashboard tab to the Flutter operator app that displays all EVM grants as a card-based grid. Each card shows a compact summary (type, chain, wallet address, client name) with a revoke action. The tab integrates into the existing `AdaptiveScaffold` navigation alongside Wallets, Clients, and About.
+Add a "Grants" dashboard tab to the Flutter user-agent app that displays all EVM grants as a card-based grid. Each card shows a compact summary (type, chain, wallet address, client name) with a revoke action. The tab integrates into the existing `AdaptiveScaffold` navigation alongside Wallets, Clients, and About.
 
 ## Scope
 
@@ -23,7 +23,7 @@ Add a "Grants" dashboard tab to the Flutter operator app that displays all EVM g
 
 ### `walletAccessListProvider`
 
-**File:** `operator/lib/providers/sdk_clients/wallet_access_list.dart`
+**File:** `useragent/lib/providers/sdk_clients/wallet_access_list.dart`
 
 - `@riverpod` class, watches `connectionManagerProvider.future`
 - Returns `List<SdkClientWalletAccess>?` (null when not connected)
@@ -85,7 +85,7 @@ NavigationDestination(
 
 ## Screen: `EvmGrantsScreen`
 
-**File:** `operator/lib/screens/dashboard/evm/grants/grants.dart`
+**File:** `useragent/lib/screens/dashboard/evm/grants/grants.dart`
 
 ```
 Scaffold

mise.lock

@@ -1,59 +1,55 @@
 # @generated - this file is auto-generated by `mise lock` https://mise.jdx.dev/dev-tools/mise-lock.html
 
 [[tools.ast-grep]]
-version = "0.42.1"
+version = "0.42.0"
 backend = "aqua:ast-grep/ast-grep"
 
 [tools.ast-grep."platforms.linux-arm64"]
-checksum = "sha256:3ba383839044cf9817929435f5ce0027f91d06931e8efb32d942e58d73d92be5"
+checksum = "sha256:5c830eae8456569e2f7212434ed9c238f58dca412d76045418ed6d394a755836"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-unknown-linux-gnu.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-arm64-musl"]
-checksum = "sha256:3ba383839044cf9817929435f5ce0027f91d06931e8efb32d942e58d73d92be5"
+checksum = "sha256:5c830eae8456569e2f7212434ed9c238f58dca412d76045418ed6d394a755836"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-unknown-linux-gnu.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-x64"]
-checksum = "sha256:5de8b87cba67fc8dc3e239d54b6484802ad745a7ae3de76be4fe89661dc52657"
+checksum = "sha256:e825a05603f0bcc4cd9076c4cc8c9abd6d008b7cd07d9aa3cc323ba4b8606651"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-unknown-linux-gnu.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-x64-musl"]
-checksum = "sha256:5de8b87cba67fc8dc3e239d54b6484802ad745a7ae3de76be4fe89661dc52657"
+checksum = "sha256:e825a05603f0bcc4cd9076c4cc8c9abd6d008b7cd07d9aa3cc323ba4b8606651"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-unknown-linux-gnu.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.macos-arm64"]
-checksum = "sha256:c3961d8e8a4ee0ce2d0d98c7beeb168bb331cdc766b53630118a7b6c4fd39015"
+checksum = "sha256:fc300d5293b1c770a5aece03a8a193b92e71e87cec726c28096990691a582620"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-apple-darwin.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-apple-darwin.zip"
 
 [tools.ast-grep."platforms.macos-x64"]
-checksum = "sha256:a038965bfd7fe44257c771cdf8918dc3467dd8ec0eef673b8b14f639b144cdbd"
+checksum = "sha256:979ffe611327056f4730a1ae71b0209b3b830f58b22c6ed194cda34f55400db2"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-apple-darwin.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-apple-darwin.zip"
 
 [tools.ast-grep."platforms.windows-x64"]
-checksum = "sha256:fe34f631bb24c08ad146f92ca2a92971a53d179461b509fd8d32dc863bff9f83"
+checksum = "sha256:55836fa1b2c65dc7d61615a4d9368622a0d2371a76d28b9a165e5a3ab6ae32a4"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-pc-windows-msvc.zip"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-pc-windows-msvc.zip"
 
 [[tools."cargo:cargo-audit"]]
 version = "0.22.1"
 backend = "cargo:cargo-audit"
 
 [[tools."cargo:cargo-edit"]]
-version = "0.13.10"
+version = "0.13.9"
 backend = "cargo:cargo-edit"
 
 [[tools."cargo:cargo-features-manager"]]
-version = "0.12.0"
+version = "0.11.1"
 backend = "cargo:cargo-features-manager"
 
 [[tools."cargo:cargo-insta"]]
-version = "1.47.2"
+version = "1.46.3"
 backend = "cargo:cargo-insta"
 
-[[tools."cargo:cargo-mutants"]]
-version = "27.0.0"
-backend = "cargo:cargo-mutants"
-
 [[tools."cargo:cargo-nextest"]]
-version = "0.9.133"
+version = "0.9.126"
 backend = "cargo:cargo-nextest"
 
 [[tools."cargo:cargo-shear"]]
@@ -65,19 +61,15 @@ version = "0.10.2"
 backend = "cargo:cargo-vet"
 
 [[tools."cargo:diesel_cli"]]
-version = "2.3.7"
+version = "2.3.6"
 backend = "cargo:diesel_cli"
 
 [tools."cargo:diesel_cli".options]
 default-features = "false"
 features = "sqlite,sqlite-bundled"
 
-[[tools."cargo:flutter_rust_bridge_codegen"]]
-version = "2.12.0"
-backend = "cargo:flutter_rust_bridge_codegen"
-
 [[tools.flutter]]
-version = "3.41.7-stable"
+version = "3.38.9-stable"
 backend = "asdf:flutter"
 
 [[tools.protoc]]
@@ -113,44 +105,37 @@ checksum = "sha256:1ebd7c87baffb9f1c47169b640872bf5fb1e4408079c691af527be9561d8f
 url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-win64.zip"
 
 [[tools.python]]
-version = "3.14.4"
+version = "3.14.3"
 backend = "core:python"
 
 [tools.python."platforms.linux-arm64"]
-checksum = "sha256:b8b597fdb2f8dccdc502c11947b60a4b65eb6bce79cfa60c7ccf9b6e8352c60a"
+checksum = "sha256:53700338695e402a1a1fe22be4a41fbdacc70e22bb308a48eca8ed67cb7992be"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-aarch64-unknown-linux-gnu-install_only_stripped.tar.gz"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-aarch64-unknown-linux-gnu-install_only_stripped.tar.gz"
-provenance = "github-attestations"
 
 [tools.python."platforms.linux-arm64-musl"]
-checksum = "sha256:b8b597fdb2f8dccdc502c11947b60a4b65eb6bce79cfa60c7ccf9b6e8352c60a"
+checksum = "sha256:53700338695e402a1a1fe22be4a41fbdacc70e22bb308a48eca8ed67cb7992be"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-aarch64-unknown-linux-gnu-install_only_stripped.tar.gz"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-aarch64-unknown-linux-gnu-install_only_stripped.tar.gz"
-provenance = "github-attestations"
 
 [tools.python."platforms.linux-x64"]
-checksum = "sha256:fe9a9c32d13870af632cbac3dfc7528ae53597e94472aa4c7d6a42e8166136cd"
+checksum = "sha256:d7a9f970914bb4c88756fe3bdcc186d4feb90e9500e54f1db47dae4dc9687e39"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz"
-provenance = "github-attestations"
 
 [tools.python."platforms.linux-x64-musl"]
-checksum = "sha256:fe9a9c32d13870af632cbac3dfc7528ae53597e94472aa4c7d6a42e8166136cd"
+checksum = "sha256:d7a9f970914bb4c88756fe3bdcc186d4feb90e9500e54f1db47dae4dc9687e39"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz"
-provenance = "github-attestations"
 
 [tools.python."platforms.macos-arm64"]
-checksum = "blake3:0314ec66e0f33ec04959583b5900bc8edae371a396aa96b8874e750d1fe936e6"
+checksum = "sha256:c43aecde4a663aebff99b9b83da0efec506479f1c3f98331442f33d2c43501f9"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-aarch64-apple-darwin-install_only_stripped.tar.gz"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-aarch64-apple-darwin-install_only_stripped.tar.gz"
-provenance = "github-attestations"
 
 [tools.python."platforms.macos-x64"]
-checksum = "sha256:d51250a32fa5d9f0799c7bcb71720c27b10a3afd4a7de288120f96085d508a5a"
+checksum = "sha256:9ab41dbc2f100a2a45d1833b9c11165f51051c558b5213eda9a9731d5948a0c0"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-x86_64-apple-darwin-install_only_stripped.tar.gz"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-x86_64-apple-darwin-install_only_stripped.tar.gz"
-provenance = "github-attestations"
 
 [tools.python."platforms.windows-x64"]
-checksum = "sha256:a976991dcd085c1bb5d9a8084823a6bc8b7f9b079d8c432574a6ddd68c3a6fe1"
+checksum = "sha256:bbe19034b35b0267176a7442575ae7dc6343480fd4d35598cb7700173d431e09"
-url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260414/cpython-3.14.4+20260414-x86_64-pc-windows-msvc-install_only_stripped.tar.gz"
+url = "https://github.com/astral-sh/python-build-standalone/releases/download/20260324/cpython-3.14.3+20260324-x86_64-pc-windows-msvc-install_only_stripped.tar.gz"
-provenance = "github-attestations"
 
 [[tools.rust]]
-version = "1.95.0"
+version = "1.93.0"
 backend = "core:rust"

mise.toml

@@ -1,24 +1,22 @@
 [tools]
-"cargo:diesel_cli" = { version = "2.3.7", features = "sqlite,sqlite-bundled", default-features = "false" }
+"cargo:diesel_cli" = { version = "2.3.6", features = "sqlite,sqlite-bundled", default-features = false }
 "cargo:cargo-audit" = "0.22.1"
 "cargo:cargo-vet" = "0.10.2"
-flutter = "3.41.7-stable"
+flutter = "3.38.9-stable"
 protoc = "29.6"
-rust = { version = "1.95.0", components = "clippy,rust-analyzer" }
+"rust" = {version = "1.93.0", components = "clippy"}
-"cargo:cargo-features-manager" = "0.12.0"
+"cargo:cargo-features-manager" = "0.11.1"
-"cargo:cargo-nextest" = "0.9.133"
+"cargo:cargo-nextest" = "0.9.126"
 "cargo:cargo-shear" = "latest"
-"cargo:cargo-insta" = "1.47.2"
+"cargo:cargo-insta" = "1.46.3"
-python = "3.14.4"
+python = "3.14.3"
-ast-grep = "0.42.1"
+ast-grep = "0.42.0"
-"cargo:cargo-edit" = "0.13.10"
+"cargo:cargo-edit" = "0.13.9"
-"cargo:cargo-mutants" = "27.0.0"
-"cargo:flutter_rust_bridge_codegen" = "2.12.0"
 
 [tasks.codegen]
-sources = ['protobufs/*.proto', 'protobufs/**/*.proto']
+sources = ['protobufs/*.proto']
-outputs = ['useragent/lib/proto/**']
+outputs = ['useragent/lib/proto/*']
 run = '''
 dart pub global activate protoc_plugin && \
-protoc --dart_out=grpc:useragent/lib/proto --proto_path=protobufs/ $(find protobufs -name '*.proto' | sort)
+protoc --dart_out=grpc:useragent/lib/proto --proto_path=protobufs/ protobufs/*.proto
 '''

protobufs/arbiter.proto

@@ -3,7 +3,7 @@ syntax = "proto3";
 package arbiter;
 
 import "client.proto";
-import "operator.proto";
+import "user_agent.proto";
 
 message ServerInfo {
   string version = 1;
@@ -12,5 +12,5 @@ message ServerInfo {
 
 service ArbiterService {
   rpc Client(stream arbiter.client.ClientRequest) returns (stream arbiter.client.ClientResponse);
-  rpc Operator(stream arbiter.operator.OperatorRequest) returns (stream arbiter.operator.OperatorResponse);
+  rpc UserAgent(stream arbiter.user_agent.UserAgentRequest) returns (stream arbiter.user_agent.UserAgentResponse);
 }

protobufs/client.proto

@@ -2,24 +2,63 @@ syntax = "proto3";
 
 package arbiter.client;
 
-import "client/auth.proto";
+import "evm.proto";
-import "client/evm.proto";
+import "google/protobuf/empty.proto";
-import "client/vault.proto";
+
+message ClientInfo {
+  string name = 1;
+  optional string description = 2;
+  optional string version = 3;
+}
+
+message AuthChallengeRequest {
+  bytes pubkey = 1;
+  ClientInfo client_info = 2;
+}
+
+message AuthChallenge {
+  bytes pubkey = 1;
+  int32 nonce = 2;
+}
+
+message AuthChallengeSolution {
+  bytes signature = 1;
+}
+
+enum AuthResult {
+  AUTH_RESULT_UNSPECIFIED = 0;
+  AUTH_RESULT_SUCCESS = 1;
+  AUTH_RESULT_INVALID_KEY = 2;
+  AUTH_RESULT_INVALID_SIGNATURE = 3;
+  AUTH_RESULT_APPROVAL_DENIED = 4;
+  AUTH_RESULT_NO_USER_AGENTS_ONLINE = 5;
+  AUTH_RESULT_INTERNAL = 6;
+}
+
+enum VaultState {
+  VAULT_STATE_UNSPECIFIED = 0;
+  VAULT_STATE_UNBOOTSTRAPPED = 1;
+  VAULT_STATE_SEALED = 2;
+  VAULT_STATE_UNSEALED = 3;
+  VAULT_STATE_ERROR = 4;
+}
 
 message ClientRequest {
   int32 request_id = 4;
   oneof payload {
-    auth.Request auth = 1;
+    AuthChallengeRequest auth_challenge_request = 1;
-    vault.Request vault = 2;
+    AuthChallengeSolution auth_challenge_solution = 2;
-    evm.Request evm = 3;
+    google.protobuf.Empty query_vault_state = 3;
   }
 }
 
 message ClientResponse {
   optional int32 request_id = 7;
   oneof payload {
-    auth.Response auth = 1;
+    AuthChallenge auth_challenge = 1;
-    vault.Response vault = 2;
+    AuthResult auth_result = 2;
-    evm.Response evm = 3;
+    arbiter.evm.EvmSignTransactionResponse evm_sign_transaction = 3;
+    arbiter.evm.EvmAnalyzeTransactionResponse evm_analyze_transaction = 4;
+    VaultState vault_state = 6;
   }
 }

protobufs/client/auth.proto

@@ -1,43 +0,0 @@
-syntax = "proto3";
-
-package arbiter.client.auth;
-
-import "shared/client.proto";
-
-message AuthChallengeRequest {
-  bytes pubkey = 1;
-  arbiter.shared.ClientInfo client_info = 2;
-}
-
-message AuthChallenge {
-  uint64 timestamp_nanos = 1;
-  bytes random = 2;
-}
-
-message AuthChallengeSolution {
-  bytes signature = 1;
-}
-
-enum AuthResult {
-  AUTH_RESULT_UNSPECIFIED = 0;
-  AUTH_RESULT_SUCCESS = 1;
-  AUTH_RESULT_INVALID_KEY = 2;
-  AUTH_RESULT_INVALID_SIGNATURE = 3;
-  AUTH_RESULT_APPROVAL_DENIED = 4;
-  AUTH_RESULT_NO_OPERATORS_ONLINE = 5;
-  AUTH_RESULT_INTERNAL = 6;
-}
-
-message Request {
-  oneof payload {
-    AuthChallengeRequest challenge_request = 1;
-    AuthChallengeSolution challenge_solution = 2;
-  }
-}
-
-message Response {
-  oneof payload {
-    AuthChallenge challenge = 1;
-    AuthResult result = 2;
-  }
-}

protobufs/client/evm.proto

@@ -1,19 +0,0 @@
-syntax = "proto3";
-
-package arbiter.client.evm;
-
-import "evm.proto";
-
-message Request {
-  oneof payload {
-    arbiter.evm.EvmSignTransactionRequest sign_transaction = 1;
-    arbiter.evm.EvmAnalyzeTransactionRequest analyze_transaction = 2;
-  }
-}
-
-message Response {
-  oneof payload {
-    arbiter.evm.EvmSignTransactionResponse sign_transaction = 1;
-    arbiter.evm.EvmAnalyzeTransactionResponse analyze_transaction = 2;
-  }
-}

protobufs/client/vault.proto

@@ -1,18 +0,0 @@
-syntax = "proto3";
-
-package arbiter.client.vault;
-
-import "google/protobuf/empty.proto";
-import "shared/vault.proto";
-
-message Request {
-  oneof payload {
-    google.protobuf.Empty query_state = 1;
-  }
-}
-
-message Response {
-  oneof payload {
-    arbiter.shared.VaultState state = 1;
-  }
-}

protobufs/evm.proto

@@ -4,7 +4,6 @@ package arbiter.evm;
 
 import "google/protobuf/empty.proto";
 import "google/protobuf/timestamp.proto";
-import "shared/evm.proto";
 
 enum EvmError {
   EVM_ERROR_UNSPECIFIED = 0;
@@ -75,7 +74,71 @@ message SpecificGrant {
   }
 }
 
-// --- Operator grant management ---
+message EtherTransferMeaning {
+  bytes to = 1; // 20-byte Ethereum address
+  bytes value = 2; // U256 as big-endian bytes
+}
+
+message TokenInfo {
+  string symbol = 1;
+  bytes address = 2; // 20-byte Ethereum address
+  uint64 chain_id = 3;
+}
+
+// Mirror of token_transfers::Meaning
+message TokenTransferMeaning {
+  TokenInfo token = 1;
+  bytes to = 2; // 20-byte Ethereum address
+  bytes value = 3; // U256 as big-endian bytes
+}
+
+// Mirror of policies::SpecificMeaning
+message SpecificMeaning {
+  oneof meaning {
+    EtherTransferMeaning ether_transfer = 1;
+    TokenTransferMeaning token_transfer = 2;
+  }
+}
+
+// --- Eval error types ---
+message GasLimitExceededViolation {
+  optional bytes max_gas_fee_per_gas = 1; // U256 as big-endian bytes
+  optional bytes max_priority_fee_per_gas = 2; // U256 as big-endian bytes
+}
+
+message EvalViolation {
+  oneof kind {
+    bytes invalid_target = 1; // 20-byte Ethereum address
+    GasLimitExceededViolation gas_limit_exceeded = 2;
+    google.protobuf.Empty rate_limit_exceeded = 3;
+    google.protobuf.Empty volumetric_limit_exceeded = 4;
+    google.protobuf.Empty invalid_time = 5;
+    google.protobuf.Empty invalid_transaction_type = 6;
+  }
+}
+
+// Transaction was classified but no grant covers it
+message NoMatchingGrantError {
+  SpecificMeaning meaning = 1;
+}
+
+// Transaction was classified and a grant was found, but constraints were violated
+message PolicyViolationsError {
+  SpecificMeaning meaning = 1;
+  repeated EvalViolation violations = 2;
+}
+
+// top-level error returned when transaction evaluation fails
+message TransactionEvalError {
+  oneof kind {
+    google.protobuf.Empty contract_creation_not_supported = 1;
+    google.protobuf.Empty unsupported_transaction_type = 2;
+    NoMatchingGrantError no_matching_grant = 3;
+    PolicyViolationsError policy_violations = 4;
+  }
+}
+
+// --- UserAgent grant management ---
 message EvmGrantCreateRequest {
   SharedSettings shared = 1;
   SpecificGrant specific = 2;
@@ -134,7 +197,7 @@ message EvmSignTransactionRequest {
 message EvmSignTransactionResponse {
   oneof result {
     bytes signature = 1; // 65-byte signature: r[32] || s[32] || v[1]
-    arbiter.shared.evm.TransactionEvalError eval_error = 2;
+    TransactionEvalError eval_error = 2;
     EvmError error = 3;
   }
 }
@@ -146,8 +209,8 @@ message EvmAnalyzeTransactionRequest {
 
 message EvmAnalyzeTransactionResponse {
   oneof result {
-    arbiter.shared.evm.SpecificMeaning meaning = 1;
+    SpecificMeaning meaning = 1;
-    arbiter.shared.evm.TransactionEvalError eval_error = 2;
+    TransactionEvalError eval_error = 2;
     EvmError error = 3;
   }
 }

protobufs/operator.proto

@@ -1,28 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator;
-
-import "operator/auth.proto";
-import "operator/evm.proto";
-import "operator/sdk_client.proto";
-import "operator/vault/vault.proto";
-
-message OperatorRequest {
-  int32 id = 16;
-  oneof payload {
-    auth.Request auth = 1;
-    vault.Request vault = 2;
-    evm.Request evm = 3;
-    sdk_client.Request sdk_client = 4;
-  }
-}
-
-message OperatorResponse {
-  optional int32 id = 16;
-  oneof payload {
-    auth.Response auth = 1;
-    vault.Response vault = 2;
-    evm.Response evm = 3;
-    sdk_client.Response sdk_client = 4;
-  }
-}

protobufs/operator/auth.proto

@@ -1,41 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.auth;
-
-message AuthChallengeRequest {
-  bytes pubkey = 1;
-  optional string bootstrap_token = 2;
-}
-
-message AuthChallenge {
-  uint64 timestamp_nanos = 1;
-  bytes random = 2;
-}
-
-message AuthChallengeSolution {
-  bytes signature = 1;
-}
-
-enum AuthResult {
-  AUTH_RESULT_UNSPECIFIED = 0;
-  AUTH_RESULT_SUCCESS = 1;
-  AUTH_RESULT_INVALID_KEY = 2;
-  AUTH_RESULT_INVALID_SIGNATURE = 3;
-  AUTH_RESULT_BOOTSTRAP_REQUIRED = 4;
-  AUTH_RESULT_TOKEN_INVALID = 5;
-  AUTH_RESULT_INTERNAL = 6;
-}
-
-message Request {
-  oneof payload {
-    AuthChallengeRequest challenge_request = 1;
-    AuthChallengeSolution challenge_solution = 2;
-  }
-}
-
-message Response {
-  oneof payload {
-    AuthChallenge challenge = 1;
-    AuthResult result = 2;
-  }
-}

protobufs/operator/evm.proto

@@ -1,33 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.evm;
-
-import "evm.proto";
-import "google/protobuf/empty.proto";
-
-message SignTransactionRequest {
-  int32 client_id = 1;
-  arbiter.evm.EvmSignTransactionRequest request = 2;
-}
-
-message Request {
-  oneof payload {
-    google.protobuf.Empty wallet_create = 1;
-    google.protobuf.Empty wallet_list = 2;
-    arbiter.evm.EvmGrantCreateRequest grant_create = 3;
-    arbiter.evm.EvmGrantDeleteRequest grant_delete = 4;
-    arbiter.evm.EvmGrantListRequest grant_list = 5;
-    SignTransactionRequest sign_transaction = 6;
-  }
-}
-
-message Response {
-  oneof payload {
-    arbiter.evm.WalletCreateResponse wallet_create = 1;
-    arbiter.evm.WalletListResponse wallet_list = 2;
-    arbiter.evm.EvmGrantCreateResponse grant_create = 3;
-    arbiter.evm.EvmGrantDeleteResponse grant_delete = 4;
-    arbiter.evm.EvmGrantListResponse grant_list = 5;
-    arbiter.evm.EvmSignTransactionResponse sign_transaction = 6;
-  }
-}

protobufs/operator/sdk_client.proto

@@ -1,100 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.sdk_client;
-
-import "shared/client.proto";
-import "google/protobuf/empty.proto";
-
-enum Error {
-  ERROR_UNSPECIFIED = 0;
-  ERROR_ALREADY_EXISTS = 1;
-  ERROR_NOT_FOUND = 2;
-  ERROR_HAS_RELATED_DATA = 3; // hard-delete blocked by FK (client has grants or transaction logs)
-  ERROR_INTERNAL = 4;
-}
-
-message RevokeRequest {
-  int32 client_id = 1;
-}
-
-message Entry {
-  int32 id = 1;
-  bytes pubkey = 2;
-  arbiter.shared.ClientInfo info = 3;
-  int32 created_at = 4;
-}
-
-message List {
-  repeated Entry clients = 1;
-}
-
-message RevokeResponse {
-  oneof result {
-    google.protobuf.Empty ok = 1;
-    Error error = 2;
-  }
-}
-
-message ListResponse {
-  oneof result {
-    List clients = 1;
-    Error error = 2;
-  }
-}
-
-message ConnectionRequest {
-  bytes pubkey = 1;
-  arbiter.shared.ClientInfo info = 2;
-}
-
-message ConnectionResponse {
-  bool approved = 1;
-  bytes pubkey = 2;
-}
-
-message ConnectionCancel {
-  bytes pubkey = 1;
-}
-
-message WalletAccess {
-  int32 wallet_id = 1;
-  int32 sdk_client_id = 2;
-}
-
-message WalletAccessEntry {
-  int32 id = 1;
-  WalletAccess access = 2;
-}
-
-message GrantWalletAccess {
-  repeated WalletAccess accesses = 1;
-}
-
-message RevokeWalletAccess {
-  repeated int32 accesses = 1;
-}
-
-message ListWalletAccessResponse {
-  repeated WalletAccessEntry accesses = 1;
-}
-
-message Request {
-  oneof payload {
-    ConnectionResponse connection_response = 1;
-    RevokeRequest revoke = 2;
-    google.protobuf.Empty list = 3;
-    GrantWalletAccess grant_wallet_access = 4;
-    RevokeWalletAccess revoke_wallet_access = 5;
-    google.protobuf.Empty list_wallet_access = 6;
-  }
-}
-
-message Response {
-  oneof payload {
-    ConnectionRequest connection_request = 1;
-    ConnectionCancel connection_cancel = 2;
-    RevokeResponse revoke = 3;
-    ListResponse list = 4;
-    ListWalletAccessResponse list_wallet_access = 5;
-  }
-}

protobufs/operator/vault/bootstrap.proto

@@ -1,24 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.vault.bootstrap;
-
-message BootstrapEncryptedKey {
-  bytes nonce = 1;
-  bytes ciphertext = 2;
-  bytes associated_data = 3;
-}
-
-enum BootstrapResult {
-  BOOTSTRAP_RESULT_UNSPECIFIED = 0;
-  BOOTSTRAP_RESULT_SUCCESS = 1;
-  BOOTSTRAP_RESULT_ALREADY_BOOTSTRAPPED = 2;
-  BOOTSTRAP_RESULT_INVALID_KEY = 3;
-}
-
-message Request {
-  BootstrapEncryptedKey encrypted_key = 2;
-}
-
-message Response {
-  BootstrapResult result = 1;
-}

protobufs/operator/vault/unseal.proto

@@ -1,37 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.vault.unseal;
-
-message UnsealStart {
-  bytes client_pubkey = 1;
-}
-
-message UnsealStartResponse {
-  bytes server_pubkey = 1;
-}
-message UnsealEncryptedKey {
-  bytes nonce = 1;
-  bytes ciphertext = 2;
-  bytes associated_data = 3;
-}
-
-enum UnsealResult {
-  UNSEAL_RESULT_UNSPECIFIED = 0;
-  UNSEAL_RESULT_SUCCESS = 1;
-  UNSEAL_RESULT_INVALID_KEY = 2;
-  UNSEAL_RESULT_UNBOOTSTRAPPED = 3;
-}
-
-message Request {
-  oneof payload {
-    UnsealStart start = 1;
-    UnsealEncryptedKey encrypted_key = 2;
-  }
-}
-
-message Response {
-  oneof payload {
-    UnsealStartResponse start = 1;
-    UnsealResult result = 2;
-  }
-}

protobufs/operator/vault/vault.proto

@@ -1,24 +0,0 @@
-syntax = "proto3";
-
-package arbiter.operator.vault;
-
-import "google/protobuf/empty.proto";
-import "shared/vault.proto";
-import "operator/vault/bootstrap.proto";
-import "operator/vault/unseal.proto";
-
-message Request {
-  oneof payload {
-    google.protobuf.Empty query_state = 1;
-    unseal.Request unseal = 2;
-    bootstrap.Request bootstrap = 3;
-  }
-}
-
-message Response {
-  oneof payload {
-    arbiter.shared.VaultState state = 1;
-    unseal.Response unseal = 2;
-    bootstrap.Response bootstrap = 3;
-  }
-}

protobufs/shared/client.proto

@@ -1,9 +0,0 @@
-syntax = "proto3";
-
-package arbiter.shared;
-
-message ClientInfo {
-  string name = 1;
-  optional string description = 2;
-  optional string version = 3;
-}

protobufs/shared/evm.proto

@@ -1,74 +0,0 @@
-syntax = "proto3";
-
-package arbiter.shared.evm;
-
-import "google/protobuf/empty.proto";
-
-message EtherTransferMeaning {
-  bytes to = 1; // 20-byte Ethereum address
-  bytes value = 2; // U256 as big-endian bytes
-}
-
-message TokenInfo {
-  string symbol = 1;
-  bytes address = 2; // 20-byte Ethereum address
-  uint64 chain_id = 3;
-}
-
-// Mirror of token_transfers::Meaning
-message TokenTransferMeaning {
-  TokenInfo token = 1;
-  bytes to = 2; // 20-byte Ethereum address
-  bytes value = 3; // U256 as big-endian bytes
-}
-
-// Mirror of policies::SpecificMeaning
-message SpecificMeaning {
-  oneof meaning {
-    EtherTransferMeaning ether_transfer = 1;
-    TokenTransferMeaning token_transfer = 2;
-  }
-}
-
-message GasLimitExceededViolation {
-  optional bytes max_gas_fee_per_gas = 1; // U256 as big-endian bytes
-  optional bytes max_priority_fee_per_gas = 2; // U256 as big-endian bytes
-}
-
-message EvalViolation {
-  message ChainIdMismatch {
-    uint64 expected = 1;
-    uint64 actual = 2;
-  }
-  oneof kind {
-    bytes invalid_target = 1; // 20-byte Ethereum address
-    GasLimitExceededViolation gas_limit_exceeded = 2;
-    google.protobuf.Empty rate_limit_exceeded = 3;
-    google.protobuf.Empty volumetric_limit_exceeded = 4;
-    google.protobuf.Empty invalid_time = 5;
-    google.protobuf.Empty invalid_transaction_type = 6;
-
-    ChainIdMismatch chain_id_mismatch = 7;
-  }
-}
-
-// Transaction was classified but no grant covers it
-message NoMatchingGrantError {
-  SpecificMeaning meaning = 1;
-}
-
-// Transaction was classified and a grant was found, but constraints were violated
-message PolicyViolationsError {
-  SpecificMeaning meaning = 1;
-  repeated EvalViolation violations = 2;
-}
-
-// top-level error returned when transaction evaluation fails
-message TransactionEvalError {
-  oneof kind {
-    google.protobuf.Empty contract_creation_not_supported = 1;
-    google.protobuf.Empty unsupported_transaction_type = 2;
-    NoMatchingGrantError no_matching_grant = 3;
-    PolicyViolationsError policy_violations = 4;
-  }
-}

protobufs/shared/vault.proto

@@ -1,11 +0,0 @@
-syntax = "proto3";
-
-package arbiter.shared;
-
-enum VaultState {
-  VAULT_STATE_UNSPECIFIED = 0;
-  VAULT_STATE_UNBOOTSTRAPPED = 1;
-  VAULT_STATE_SEALED = 2;
-  VAULT_STATE_UNSEALED = 3;
-  VAULT_STATE_ERROR = 4;
-}

protobufs/user_agent.proto

@@ -0,0 +1,199 @@
+syntax = "proto3";
+
+package arbiter.user_agent;
+
+import "client.proto";
+import "evm.proto";
+import "google/protobuf/empty.proto";
+
+enum KeyType {
+  KEY_TYPE_UNSPECIFIED = 0;
+  KEY_TYPE_ED25519 = 1;
+  KEY_TYPE_ECDSA_SECP256K1 = 2;
+  KEY_TYPE_RSA = 3;
+}
+
+// --- SDK client management ---
+
+enum SdkClientError {
+  SDK_CLIENT_ERROR_UNSPECIFIED = 0;
+  SDK_CLIENT_ERROR_ALREADY_EXISTS = 1;
+  SDK_CLIENT_ERROR_NOT_FOUND = 2;
+  SDK_CLIENT_ERROR_HAS_RELATED_DATA = 3; // hard-delete blocked by FK (client has grants or transaction logs)
+  SDK_CLIENT_ERROR_INTERNAL = 4;
+}
+
+message SdkClientRevokeRequest {
+  int32 client_id = 1;
+}
+
+message SdkClientEntry {
+  int32 id = 1;
+  bytes pubkey = 2;
+  arbiter.client.ClientInfo info = 3;
+  int32 created_at = 4;
+}
+
+message SdkClientList {
+  repeated SdkClientEntry clients = 1;
+}
+
+message SdkClientRevokeResponse {
+  oneof result {
+    google.protobuf.Empty ok = 1;
+    SdkClientError error = 2;
+  }
+}
+
+message SdkClientListResponse {
+  oneof result {
+    SdkClientList clients = 1;
+    SdkClientError error = 2;
+  }
+}
+
+message AuthChallengeRequest {
+  bytes pubkey = 1;
+  optional string bootstrap_token = 2;
+  KeyType key_type = 3;
+}
+
+message AuthChallenge {
+  int32 nonce = 2;
+  reserved 1;
+}
+
+message AuthChallengeSolution {
+  bytes signature = 1;
+}
+
+enum AuthResult {
+  AUTH_RESULT_UNSPECIFIED = 0;
+  AUTH_RESULT_SUCCESS = 1;
+  AUTH_RESULT_INVALID_KEY = 2;
+  AUTH_RESULT_INVALID_SIGNATURE = 3;
+  AUTH_RESULT_BOOTSTRAP_REQUIRED = 4;
+  AUTH_RESULT_TOKEN_INVALID = 5;
+  AUTH_RESULT_INTERNAL = 6;
+}
+
+message UnsealStart {
+  bytes client_pubkey = 1;
+}
+
+message UnsealStartResponse {
+  bytes server_pubkey = 1;
+}
+message UnsealEncryptedKey {
+  bytes nonce = 1;
+  bytes ciphertext = 2;
+  bytes associated_data = 3;
+}
+
+message BootstrapEncryptedKey {
+  bytes nonce = 1;
+  bytes ciphertext = 2;
+  bytes associated_data = 3;
+}
+
+enum UnsealResult {
+  UNSEAL_RESULT_UNSPECIFIED = 0;
+  UNSEAL_RESULT_SUCCESS = 1;
+  UNSEAL_RESULT_INVALID_KEY = 2;
+  UNSEAL_RESULT_UNBOOTSTRAPPED = 3;
+}
+
+enum BootstrapResult {
+  BOOTSTRAP_RESULT_UNSPECIFIED = 0;
+  BOOTSTRAP_RESULT_SUCCESS = 1;
+  BOOTSTRAP_RESULT_ALREADY_BOOTSTRAPPED = 2;
+  BOOTSTRAP_RESULT_INVALID_KEY = 3;
+}
+
+enum VaultState {
+  VAULT_STATE_UNSPECIFIED = 0;
+  VAULT_STATE_UNBOOTSTRAPPED = 1;
+  VAULT_STATE_SEALED = 2;
+  VAULT_STATE_UNSEALED = 3;
+  VAULT_STATE_ERROR = 4;
+}
+
+message SdkClientConnectionRequest {
+  bytes pubkey = 1;
+  arbiter.client.ClientInfo info = 2;
+}
+
+message SdkClientConnectionResponse {
+  bool approved = 1;
+  bytes pubkey = 2;
+}
+
+message SdkClientConnectionCancel {
+  bytes pubkey = 1;
+}
+
+message WalletAccess {
+  int32 wallet_id = 1;
+  int32 sdk_client_id = 2;
+}
+
+message SdkClientWalletAccess {
+  int32 id = 1;
+  WalletAccess access = 2;
+}
+
+message SdkClientGrantWalletAccess {
+  repeated WalletAccess accesses = 1;
+}
+
+message SdkClientRevokeWalletAccess {
+  repeated int32 accesses = 1;
+}
+
+message ListWalletAccessResponse {
+  repeated SdkClientWalletAccess accesses = 1;
+}
+
+message UserAgentRequest {
+  int32 id = 16;
+  oneof payload {
+    AuthChallengeRequest auth_challenge_request = 1;
+    AuthChallengeSolution auth_challenge_solution = 2;
+    UnsealStart unseal_start = 3;
+    UnsealEncryptedKey unseal_encrypted_key = 4;
+    google.protobuf.Empty query_vault_state = 5;
+    google.protobuf.Empty evm_wallet_create = 6;
+    google.protobuf.Empty evm_wallet_list = 7;
+    arbiter.evm.EvmGrantCreateRequest evm_grant_create = 8;
+    arbiter.evm.EvmGrantDeleteRequest evm_grant_delete = 9;
+    arbiter.evm.EvmGrantListRequest evm_grant_list = 10;
+    SdkClientConnectionResponse sdk_client_connection_response = 11;
+    SdkClientRevokeRequest sdk_client_revoke = 12;
+    google.protobuf.Empty sdk_client_list = 13;
+    BootstrapEncryptedKey bootstrap_encrypted_key = 14;
+    SdkClientGrantWalletAccess grant_wallet_access = 15;
+    SdkClientRevokeWalletAccess revoke_wallet_access = 17;
+    google.protobuf.Empty list_wallet_access = 18;
+  }
+}
+message UserAgentResponse {
+  optional int32 id = 16;
+  oneof payload {
+    AuthChallenge auth_challenge = 1;
+    AuthResult auth_result = 2;
+    UnsealStartResponse unseal_start_response = 3;
+    UnsealResult unseal_result = 4;
+    VaultState vault_state = 5;
+    arbiter.evm.WalletCreateResponse evm_wallet_create = 6;
+    arbiter.evm.WalletListResponse evm_wallet_list = 7;
+    arbiter.evm.EvmGrantCreateResponse evm_grant_create = 8;
+    arbiter.evm.EvmGrantDeleteResponse evm_grant_delete = 9;
+    arbiter.evm.EvmGrantListResponse evm_grant_list = 10;
+    SdkClientConnectionRequest sdk_client_connection_request = 11;
+    SdkClientConnectionCancel sdk_client_connection_cancel = 12;
+    SdkClientRevokeResponse sdk_client_revoke_response = 13;
+    SdkClientListResponse sdk_client_list_response = 14;
+    BootstrapResult bootstrap_result = 15;
+    ListWalletAccessResponse list_wallet_access_response = 17;
+  }
+}

server/.cargo/mutants.toml

@@ -1 +0,0 @@
-test_tool = "nextest"

server/.gitignore

@@ -1,2 +0,0 @@
-mutants.out/
-mutants.out.old/

server/Cargo.toml

@@ -4,170 +4,42 @@ members = [
 ]
 resolver = "3"
 
+[workspace.lints.clippy]
+disallowed-methods = "deny"
+
 
 [workspace.dependencies]
-alloy = "2.0.0"
+tonic = { version = "0.14.5", features = [
-async-trait = "0.1.89"
+    "deflate",
-base64 = "0.22.1"
+    "gzip",
-chrono = { version = "0.4.44", features = ["serde"] }
+    "tls-connect-info",
-ed25519-dalek = { version = "3.0.0-pre.6", features = ["rand_core"] }
+    "zstd",
-futures = "0.3.32"
+] }
-k256 = { version = "0.13.4", features = ["ecdsa", "pkcs8"] }
-kameo = {git = "https://github.com/hdbg/kameo.git", rev = "805b417"}
-kameo_actors = {git = "https://github.com/hdbg/kameo.git", rev = "805b417"}
-hmac = "0.13.0"
-miette = { version = "7.6.0", features = ["fancy", "serde"] }
-ml-dsa = { version = "0.1.0-rc.8", features = ["zeroize"] }
-mutants = "0.0.4"
-prost = "0.14.3"
-prost-types = { version = "0.14.3", features = ["chrono"] }
-rand = "0.10.1"
-rcgen = { version = "0.14.7", features = [ "aws_lc_rs",  "pem", "x509-parser", "zeroize" ], default-features = false }
-rsa = { version = "0.9", features = ["sha2"] }
-rstest = "0.26.1"
-rustls = { version = "0.23.38", features = ["aws-lc-rs", "logging", "prefer-post-quantum", "std"], default-features = false }
-rustls-pki-types = "1.14.0"
-sha2 = "0.11"
-smlang = "0.8.0"
-spki = "0.8"
-thiserror = "2.0.18"
-tokio = { version = "1.52.1", features = ["full"] }
-tokio-stream = { version = "0.1.18", features = ["full"] }
-tonic = { version = "0.14.5", features = [ "deflate", "gzip", "tls-connect-info", "zstd" ] }
 tracing = "0.1.44"
+tokio = { version = "1.50.0", features = ["full"] }
+ed25519-dalek = { version = "3.0.0-pre.6", features = ["rand_core"] }
+chrono = { version = "0.4.44", features = ["serde"] }
+rand = "0.10.0"
+rustls = { version = "0.23.37", features = ["aws-lc-rs"] }
+smlang = "0.8.0"
+miette = { version = "7.6.0", features = ["fancy", "serde"] }
+thiserror = "2.0.18"
+async-trait = "0.1.89"
+futures = "0.3.32"
+tokio-stream = { version = "0.1.18", features = ["full"] }
+kameo = "0.19.2"
+prost-types = { version = "0.14.3", features = ["chrono"] }
 x25519-dalek = { version = "2.0.1", features = ["getrandom"] }
-
+rstest = "0.26.1"
-[workspace.lints.rust]
+rustls-pki-types = "1.14.0"
-missing_unsafe_on_extern = "deny"
+alloy = "1.7.3"
-unsafe_attr_outside_unsafe = "deny"
+rcgen = { version = "0.14.7", features = [
-unsafe_op_in_unsafe_fn = "deny"
+    "aws_lc_rs",
-unstable_features = "deny"
+    "pem",
-
+    "x509-parser",
-deprecated_safe_2024 = "warn"
+    "zeroize",
-ffi_unwind_calls = "warn"
+], default-features = false }
-linker_messages = "warn"
+k256 = { version = "0.13.4", features = ["ecdsa", "pkcs8"] }
-
+rsa = { version = "0.9", features = ["sha2"] }
-elided_lifetimes_in_paths = "warn"
+sha2 = "0.10"
-explicit_outlives_requirements = "warn"
+spki = "0.7"
-impl-trait-overcaptures = "warn"
-impl-trait-redundant-captures = "warn"
-redundant_lifetimes = "warn"
-single_use_lifetimes = "warn"
-unused_lifetimes = "warn"
-
-macro_use_extern_crate = "warn"
-redundant_imports = "warn"
-unused_import_braces = "warn"
-unused_macro_rules = "warn"
-unused_qualifications = "warn"
-
-unit_bindings = "warn"
-
-# missing_docs = "warn" # ENABLE BY THE FIRST MAJOR VERSION!!
-unnameable_types = "warn"
-
-[workspace.lints.clippy]
-derive_partial_eq_without_eq = "allow" 
-future_not_send = "allow"
-inconsistent_struct_constructor = "allow"
-inline_always = "allow"
-missing_errors_doc = "allow"
-missing_fields_in_debug = "allow"
-missing_panics_doc = "allow"
-must_use_candidate = "allow"
-needless_pass_by_ref_mut = "allow"
-pub_underscore_fields = "allow"
-redundant_pub_crate = "allow" 
-uninhabited_references = "allow" # safe with unsafe_code = "forbid" and standard uninhabited pattern (match *self {})
-
-# restriction lints
-alloc_instead_of_core = "warn"
-allow_attributes_without_reason = "warn"
-as_conversions = "warn"
-assertions_on_result_states = "warn"
-cfg_not_test = "warn"
-clone_on_ref_ptr = "warn"
-cognitive_complexity = "warn"
-create_dir = "warn"
-dbg_macro = "warn"
-decimal_literal_representation = "warn"
-default_union_representation = "warn"
-deref_by_slicing = "warn"
-disallowed_script_idents = "warn"
-doc_include_without_cfg = "warn"
-empty_drop = "warn"
-empty_enum_variants_with_brackets = "warn"
-empty_structs_with_brackets = "warn"
-exit = "warn"
-filetype_is_file = "warn"
-float_arithmetic = "warn"
-float_cmp_const = "warn"
-fn_to_numeric_cast_any = "warn"
-get_unwrap = "warn"
-if_then_some_else_none = "warn"
-indexing_slicing = "warn"
-infinite_loop = "warn"
-inline_asm_x86_att_syntax = "warn"
-inline_asm_x86_intel_syntax = "warn"
-integer_division = "warn"
-large_include_file = "warn"
-lossy_float_literal = "warn"
-map_with_unused_argument_over_ranges = "warn"
-mem_forget = "warn"
-missing_assert_message = "warn"
-mixed_read_write_in_expression = "warn"
-modulo_arithmetic = "warn"
-multiple_unsafe_ops_per_block = "warn"
-mutex_atomic = "warn"
-mutex_integer = "warn"
-needless_raw_strings = "warn"
-non_ascii_literal = "warn"
-non_zero_suggestions = "warn"
-pathbuf_init_then_push = "warn"
-pointer_format = "warn"
-precedence_bits = "warn"
-pub_without_shorthand = "warn"
-rc_buffer = "warn"
-rc_mutex = "warn"
-redundant_test_prefix = "warn"
-redundant_type_annotations = "warn"
-ref_patterns = "warn"
-renamed_function_params = "warn"
-rest_pat_in_fully_bound_structs = "warn"
-return_and_then = "warn"
-semicolon_inside_block = "warn"
-str_to_string = "warn"
-string_add = "warn"
-string_lit_chars_any = "warn"
-string_slice = "warn"
-suspicious_xor_used_as_pow = "warn"
-try_err = "warn"
-undocumented_unsafe_blocks = "warn"
-uninlined_format_args = "warn"
-unnecessary_safety_comment = "warn"
-unnecessary_safety_doc = "warn"
-unnecessary_self_imports = "warn"
-unneeded_field_pattern = "warn"
-unused_result_ok = "warn"
-verbose_file_reads = "warn"
-
-# cargo lints
-negative_feature_names = "warn"
-redundant_feature_names = "warn"
-wildcard_dependencies = "warn"
-
-# ENABLE BY THE FIRST MAJOR VERSION!!
-# todo = "warn"
-# unimplemented = "warn"
-# panic = "warn"
-# panic_in_result_fn = "warn"
-# 
-# cargo_common_metadata = "warn"
-# multiple_crate_versions = "warn" # a controversial option since it's really difficult to maintain
-
-disallowed_methods = "deny"
-
-nursery = { level = "warn", priority = -1 }
-pedantic = { level = "warn", priority = -1 }
-
-type_repetition_in_bounds = "allow"   # sometimes, it's better for readability this way

server/clippy.toml

@@ -7,22 +7,3 @@ disallowed-methods = [
     { path = "rsa::traits::Decryptor::decrypt", reason = "RSA decryption is forbidden (RUSTSEC-2023-0071 Marvin Attack). This blocks decrypt() on rsa::{pkcs1v15,oaep}::DecryptingKey." },
     { path = "rsa::traits::RandomizedDecryptor::decrypt_with_rng", reason = "RSA decryption is forbidden (RUSTSEC-2023-0071 Marvin Attack). This blocks decrypt_with_rng() on rsa::{pkcs1v15,oaep}::DecryptingKey." },
 ]
-
-allow-indexing-slicing-in-tests = true
-allow-panic-in-tests = true
-check-inconsistent-struct-field-initializers = true
-suppress-restriction-lint-in-const = true
-allow-renamed-params-for = [
-    "core::convert::From",
-    "core::convert::TryFrom",
-    "core::str::FromStr",
-    "kameo::actor::Actor",
-]
-
-module-items-ordered-within-groupings = ["UPPER_SNAKE_CASE"]
-source-item-ordering = ["enum"]
-trait-assoc-item-kinds-order = [
-    "const",
-    "type",
-    "fn",
-] # community tested standard

server/crates/arbiter-client/Cargo.toml

@@ -13,15 +13,14 @@ evm = ["dep:alloy"]
 
 [dependencies]
 arbiter-proto.path = "../arbiter-proto"
-arbiter-crypto.path = "../arbiter-crypto"
 alloy = { workspace = true, optional = true }
 tonic.workspace = true
 tonic.features = ["tls-aws-lc"]
 tokio.workspace = true
 tokio-stream.workspace = true
+ed25519-dalek.workspace = true
 thiserror.workspace = true
 http = "1.4.0"
-rustls-webpki = { version = "0.103.12", features = ["aws-lc-rs"] }
+rustls-webpki = { version = "0.103.10", features = ["aws-lc-rs"] }
 async-trait.workspace = true
 rand.workspace = true
-chrono.workspace = true

server/crates/arbiter-client/src/auth.rs

@@ -1,50 +1,40 @@
+use arbiter_proto::{
+    ClientMetadata, format_challenge,
+    proto::client::{
+        AuthChallengeRequest, AuthChallengeSolution, AuthResult, ClientInfo as ProtoClientInfo,
+        ClientRequest, client_request::Payload as ClientRequestPayload,
+        client_response::Payload as ClientResponsePayload,
+    },
+};
+use ed25519_dalek::Signer as _;
+
 use crate::{
     storage::StorageError,
     transport::{ClientTransport, next_request_id},
 };
-use arbiter_crypto::authn::{self, CLIENT_CONTEXT, SigningKey};
-use arbiter_proto::{
-    ClientMetadata,
-    proto::{
-        client::{
-            ClientRequest,
-            auth::{
-                self as proto_auth, AuthChallenge, AuthChallengeRequest, AuthChallengeSolution,
-                AuthResult, request::Payload as AuthRequestPayload,
-                response::Payload as AuthResponsePayload,
-            },
-            client_request::Payload as ClientRequestPayload,
-            client_response::Payload as ClientResponsePayload,
-        },
-        shared::ClientInfo as ProtoClientInfo,
-    },
-};
-
-use chrono::DateTime;
 
 #[derive(Debug, thiserror::Error)]
 pub enum AuthError {
-    #[error("Server sent invalid auth challenge")]
-    InvalidChallenge,
-    #[error("Client approval denied by Operator")]
-    ApprovalDenied,
     #[error("Auth challenge was not returned by server")]
     MissingAuthChallenge,
 
-    #[error("No Operators online to approve client")]
+    #[error("Client approval denied by User Agent")]
-    NoOperatorsOnline,
+    ApprovalDenied,
 
-    #[error("Signing key storage error")]
+    #[error("No User Agents online to approve client")]
-    Storage(#[from] StorageError),
+    NoUserAgentsOnline,
 
     #[error("Unexpected auth response payload")]
     UnexpectedAuthResponse,
+
+    #[error("Signing key storage error")]
+    Storage(#[from] StorageError),
 }
 
 fn map_auth_result(code: i32) -> AuthError {
     match AuthResult::try_from(code).unwrap_or(AuthResult::Unspecified) {
         AuthResult::ApprovalDenied => AuthError::ApprovalDenied,
-        AuthResult::NoOperatorsOnline => AuthError::NoOperatorsOnline,
+        AuthResult::NoUserAgentsOnline => AuthError::NoUserAgentsOnline,
         AuthResult::Unspecified
         | AuthResult::Success
         | AuthResult::InvalidKey
@@ -56,21 +46,21 @@ fn map_auth_result(code: i32) -> AuthError {
 async fn send_auth_challenge_request(
     transport: &mut ClientTransport,
     metadata: ClientMetadata,
-    key: &SigningKey,
+    key: &ed25519_dalek::SigningKey,
-) -> Result<(), AuthError> {
+) -> std::result::Result<(), AuthError> {
     transport
         .send(ClientRequest {
             request_id: next_request_id(),
-            payload: Some(ClientRequestPayload::Auth(proto_auth::Request {
+            payload: Some(ClientRequestPayload::AuthChallengeRequest(
-                payload: Some(AuthRequestPayload::ChallengeRequest(AuthChallengeRequest {
+                AuthChallengeRequest {
-                    pubkey: key.public_key().to_bytes(),
+                    pubkey: key.verifying_key().to_bytes().to_vec(),
                     client_info: Some(ProtoClientInfo {
                         name: metadata.name,
                         description: metadata.description,
                         version: metadata.version,
                     }),
-                })),
+                },
-            })),
+            )),
         })
         .await
         .map_err(|_| AuthError::UnexpectedAuthResponse)
@@ -78,7 +68,7 @@ async fn send_auth_challenge_request(
 
 async fn receive_auth_challenge(
     transport: &mut ClientTransport,
-) -> Result<AuthChallenge, AuthError> {
+) -> std::result::Result<arbiter_proto::proto::client::AuthChallenge, AuthError> {
     let response = transport
         .recv()
         .await
@@ -86,73 +76,58 @@ async fn receive_auth_challenge(
 
     let payload = response.payload.ok_or(AuthError::MissingAuthChallenge)?;
     match payload {
-        ClientResponsePayload::Auth(response) => match response.payload {
+        ClientResponsePayload::AuthChallenge(challenge) => Ok(challenge),
-            Some(AuthResponsePayload::Challenge(challenge)) => Ok(challenge),
+        ClientResponsePayload::AuthResult(result) => Err(map_auth_result(result)),
-            Some(AuthResponsePayload::Result(result)) => Err(map_auth_result(result)),
-            None => Err(AuthError::MissingAuthChallenge),
-        },
         _ => Err(AuthError::UnexpectedAuthResponse),
     }
 }
 
 async fn send_auth_challenge_solution(
     transport: &mut ClientTransport,
-    key: &SigningKey,
+    key: &ed25519_dalek::SigningKey,
-    challenge: AuthChallenge,
+    challenge: arbiter_proto::proto::client::AuthChallenge,
-) -> Result<(), AuthError> {
+) -> std::result::Result<(), AuthError> {
-    let timestamp = DateTime::from_timestamp_nanos(challenge.timestamp_nanos as i64);
+    let challenge_payload = format_challenge(challenge.nonce, &challenge.pubkey);
-    let challenge = authn::AuthChallenge {
+    let signature = key.sign(&challenge_payload).to_bytes().to_vec();
-        nonce: *challenge
-            .random
-            .as_array()
-            .ok_or(AuthError::InvalidChallenge)?,
-        timestamp,
-    };
-    let challenge_payload: Vec<u8> = challenge.format();
-    let signature = key
-        .sign_message(&challenge_payload, CLIENT_CONTEXT)
-        .map_err(|_| AuthError::UnexpectedAuthResponse)?
-        .to_bytes();
 
     transport
         .send(ClientRequest {
             request_id: next_request_id(),
-            payload: Some(ClientRequestPayload::Auth(proto_auth::Request {
+            payload: Some(ClientRequestPayload::AuthChallengeSolution(
-                payload: Some(AuthRequestPayload::ChallengeSolution(
+                AuthChallengeSolution { signature },
-                    AuthChallengeSolution { signature },
+            )),
-                )),
-            })),
         })
         .await
         .map_err(|_| AuthError::UnexpectedAuthResponse)
 }
 
-async fn receive_auth_confirmation(transport: &mut ClientTransport) -> Result<(), AuthError> {
+async fn receive_auth_confirmation(
+    transport: &mut ClientTransport,
+) -> std::result::Result<(), AuthError> {
     let response = transport
         .recv()
         .await
         .map_err(|_| AuthError::UnexpectedAuthResponse)?;
 
-    let payload = response.payload.ok_or(AuthError::UnexpectedAuthResponse)?;
+    let payload = response
+        .payload
+        .ok_or(AuthError::UnexpectedAuthResponse)?;
     match payload {
-        ClientResponsePayload::Auth(response) => match response.payload {
+        ClientResponsePayload::AuthResult(result)
-            Some(AuthResponsePayload::Result(result))
+            if AuthResult::try_from(result).ok() == Some(AuthResult::Success) =>
-                if AuthResult::try_from(result).ok() == Some(AuthResult::Success) =>
+        {
-            {
+            Ok(())
-                Ok(())
+        }
-            }
+        ClientResponsePayload::AuthResult(result) => Err(map_auth_result(result)),
-            Some(AuthResponsePayload::Result(result)) => Err(map_auth_result(result)),
-            _ => Err(AuthError::UnexpectedAuthResponse),
-        },
         _ => Err(AuthError::UnexpectedAuthResponse),
     }
 }
 
-pub async fn authenticate(
+pub(crate) async fn authenticate(
     transport: &mut ClientTransport,
     metadata: ClientMetadata,
-    key: &SigningKey,
+    key: &ed25519_dalek::SigningKey,
-) -> Result<(), AuthError> {
+) -> std::result::Result<(), AuthError> {
     send_auth_challenge_request(transport, metadata, key).await?;
     let challenge = receive_auth_challenge(transport).await?;
     send_auth_challenge_solution(transport, key, challenge).await?;

server/crates/arbiter-client/src/bin/test_connect.rs

@@ -1,8 +1,10 @@
-use arbiter_client::ArbiterClient;
-use arbiter_proto::{ClientMetadata, url::ArbiterUrl};
 
 use std::io::{self, Write};
 
+use arbiter_client::ArbiterClient;
+use arbiter_proto::{ClientMetadata, url::ArbiterUrl};
+use tonic::ConnectError;
+
 #[tokio::main]
 async fn main() {
     println!("Testing connection to Arbiter server...");
@@ -21,6 +23,8 @@ async fn main() {
         return;
     }
 
+   
+
     let url = match ArbiterUrl::try_from(input) {
         Ok(url) => url,
         Err(err) => {
@@ -29,16 +33,16 @@ async fn main() {
         }
     };
 
-    println!("{url:#?}");
+     println!("{:#?}", url);
 
     let metadata = ClientMetadata {
-        name: "arbiter-client test_connect".to_owned(),
+        name: "arbiter-client test_connect".to_string(),
-        description: Some("Manual connection smoke test".to_owned()),
+        description: Some("Manual connection smoke test".to_string()),
-        version: Some(env!("CARGO_PKG_VERSION").to_owned()),
+        version: Some(env!("CARGO_PKG_VERSION").to_string()),
     };
 
     match ArbiterClient::connect(url, metadata).await {
         Ok(_) => println!("Connected and authenticated successfully."),
-        Err(err) => eprintln!("Failed to connect: {err:#?}"),
+        Err(err) => eprintln!("Failed to connect: {:#?}", err),
     }
-}
+}

server/crates/arbiter-client/src/client.rs

@@ -1,55 +1,45 @@
-#[cfg(feature = "evm")]
+use arbiter_proto::{ClientMetadata, proto::arbiter_service_client::ArbiterServiceClient, url::ArbiterUrl};
-use crate::wallets::evm::ArbiterEvmWallet;
-use crate::{
-    StorageError,
-    auth::{AuthError, authenticate},
-    storage::{FileSigningKeyStorage, SigningKeyStorage},
-    transport::{BUFFER_LENGTH, ClientTransport},
-};
-use arbiter_crypto::authn::SigningKey;
-use arbiter_proto::{
-    ClientMetadata, proto::arbiter_service_client::ArbiterServiceClient, url::ArbiterUrl,
-};
-
 use std::sync::Arc;
 use tokio::sync::{Mutex, mpsc};
 use tokio_stream::wrappers::ReceiverStream;
 use tonic::transport::ClientTlsConfig;
 
+use crate::{
+    StorageError, auth::{AuthError, authenticate}, storage::{FileSigningKeyStorage, SigningKeyStorage}, transport::{BUFFER_LENGTH, ClientTransport}
+};
+
+#[cfg(feature = "evm")]
+use crate::wallets::evm::ArbiterEvmWallet;
+
 #[derive(Debug, thiserror::Error)]
-pub enum ArbiterClientError {
+pub enum Error {
-    #[error("Authentication error")]
+    #[error("gRPC error")]
-    Authentication(#[from] AuthError),
+    Grpc(#[from] tonic::Status),
 
     #[error("Could not establish connection")]
     Connection(#[from] tonic::transport::Error),
 
-    #[error("gRPC error")]
+    #[error("Invalid server URI")]
-    Grpc(#[from] tonic::Status),
+    InvalidUri(#[from] http::uri::InvalidUri),
 
     #[error("Invalid CA certificate")]
     InvalidCaCert(#[from] webpki::Error),
 
-    #[error("Invalid server URI")]
+    #[error("Authentication error")]
-    InvalidUri(#[from] http::uri::InvalidUri),
+    Authentication(#[from] AuthError),
 
     #[error("Storage error")]
     Storage(#[from] StorageError),
+    
 }
 
 pub struct ArbiterClient {
-    #[expect(
+    #[allow(dead_code)]
-        dead_code,
-        reason = "transport will be used in future methods for sending requests and receiving responses"
-    )]
     transport: Arc<Mutex<ClientTransport>>,
 }
 
 impl ArbiterClient {
-    pub async fn connect(
+    pub async fn connect(url: ArbiterUrl, metadata: ClientMetadata) -> Result<Self, Error> {
-        url: ArbiterUrl,
-        metadata: ClientMetadata,
-    ) -> Result<Self, ArbiterClientError> {
         let storage = FileSigningKeyStorage::from_default_location()?;
         Self::connect_with_storage(url, metadata, &storage).await
     }
@@ -58,7 +48,7 @@ impl ArbiterClient {
         url: ArbiterUrl,
         metadata: ClientMetadata,
         storage: &S,
-    ) -> Result<Self, ArbiterClientError> {
+    ) -> Result<Self, Error> {
         let key = storage.load_or_create()?;
         Self::connect_with_key(url, metadata, key).await
     }
@@ -66,16 +56,15 @@ impl ArbiterClient {
     pub async fn connect_with_key(
         url: ArbiterUrl,
         metadata: ClientMetadata,
-        key: SigningKey,
+        key: ed25519_dalek::SigningKey,
-    ) -> Result<Self, ArbiterClientError> {
+    ) -> Result<Self, Error> {
         let anchor = webpki::anchor_from_trusted_cert(&url.ca_cert)?.to_owned();
         let tls = ClientTlsConfig::new().trust_anchor(anchor);
 
-        let channel =
+        let channel = tonic::transport::Channel::from_shared(format!("https://{}:{}", url.host, url.port))?
-            tonic::transport::Channel::from_shared(format!("https://{}:{}", url.host, url.port))?
+            .tls_config(tls)?
-                .tls_config(tls)?
+            .connect()
-                .connect()
+            .await?;
-                .await?;
 
         let mut client = ArbiterServiceClient::new(channel);
         let (tx, rx) = mpsc::channel(BUFFER_LENGTH);
@@ -94,8 +83,7 @@ impl ArbiterClient {
     }
 
     #[cfg(feature = "evm")]
-    #[expect(clippy::unused_async, reason = "false positive")]
+    pub async fn evm_wallets(&self) -> Result<Vec<ArbiterEvmWallet>, Error> {
-    pub async fn evm_wallets(&self) -> Result<Vec<ArbiterEvmWallet>, ArbiterClientError> {
         todo!("fetch EVM wallet list from server")
     }
 }

server/crates/arbiter-client/src/lib.rs

@@ -5,8 +5,8 @@ mod transport;
 pub mod wallets;
 
 pub use auth::AuthError;
-pub use client::{ArbiterClient, ArbiterClientError};
+pub use client::{ArbiterClient, Error};
 pub use storage::{FileSigningKeyStorage, SigningKeyStorage, StorageError};
 
 #[cfg(feature = "evm")]
-pub use wallets::evm::{ArbiterEvmSignTransactionError, ArbiterEvmWallet};
+pub use wallets::evm::ArbiterEvmWallet;

server/crates/arbiter-client/src/storage.rs

@@ -1,19 +1,17 @@
-use arbiter_crypto::authn::SigningKey;
 use arbiter_proto::home_path;
-
 use std::path::{Path, PathBuf};
 
 #[derive(Debug, thiserror::Error)]
 pub enum StorageError {
-    #[error("Invalid signing key length in storage: expected {expected} bytes, got {actual} bytes")]
-    InvalidKeyLength { expected: usize, actual: usize },
-
     #[error("I/O error")]
     Io(#[from] std::io::Error),
+
+    #[error("Invalid signing key length in storage: expected {expected} bytes, got {actual} bytes")]
+    InvalidKeyLength { expected: usize, actual: usize },
 }
 
 pub trait SigningKeyStorage {
-    fn load_or_create(&self) -> Result<SigningKey, StorageError>;
+    fn load_or_create(&self) -> std::result::Result<ed25519_dalek::SigningKey, StorageError>;
 }
 
 #[derive(Debug, Clone)]
@@ -22,17 +20,17 @@ pub struct FileSigningKeyStorage {
 }
 
 impl FileSigningKeyStorage {
-    pub const DEFAULT_FILE_NAME: &str = "sdk_client_ml_dsa.key";
+    pub const DEFAULT_FILE_NAME: &str = "sdk_client_ed25519.key";
 
     pub fn new(path: impl Into<PathBuf>) -> Self {
         Self { path: path.into() }
     }
 
-    pub fn from_default_location() -> Result<Self, StorageError> {
+    pub fn from_default_location() -> std::result::Result<Self, StorageError> {
         Ok(Self::new(home_path()?.join(Self::DEFAULT_FILE_NAME)))
     }
 
-    fn read_key(path: &Path) -> Result<SigningKey, StorageError> {
+    fn read_key(path: &Path) -> std::result::Result<ed25519_dalek::SigningKey, StorageError> {
         let bytes = std::fs::read(path)?;
         let raw: [u8; 32] =
             bytes
@@ -41,12 +39,12 @@ impl FileSigningKeyStorage {
                     expected: 32,
                     actual: v.len(),
                 })?;
-        Ok(SigningKey::from_seed(raw))
+        Ok(ed25519_dalek::SigningKey::from_bytes(&raw))
     }
 }
 
 impl SigningKeyStorage for FileSigningKeyStorage {
-    fn load_or_create(&self) -> Result<SigningKey, StorageError> {
+    fn load_or_create(&self) -> std::result::Result<ed25519_dalek::SigningKey, StorageError> {
         if let Some(parent) = self.path.parent() {
             std::fs::create_dir_all(parent)?;
         }
@@ -55,8 +53,8 @@ impl SigningKeyStorage for FileSigningKeyStorage {
             return Self::read_key(&self.path);
         }
 
-        let key = SigningKey::generate();
+        let key = ed25519_dalek::SigningKey::generate(&mut rand::rng());
-        let raw_key = key.to_seed();
+        let raw_key = key.to_bytes();
 
         // Use create_new to prevent accidental overwrite if another process creates the key first.
         match std::fs::OpenOptions::new()
@@ -105,7 +103,7 @@ mod tests {
             .load_or_create()
             .expect("second load_or_create should read same key");
 
-        assert_eq!(key_a.to_seed(), key_b.to_seed());
+        assert_eq!(key_a.to_bytes(), key_b.to_bytes());
         assert!(path.exists());
 
         std::fs::remove_file(path).expect("temp key file should be removable");
@@ -126,7 +124,7 @@ mod tests {
                 assert_eq!(expected, 32);
                 assert_eq!(actual, 31);
             }
-            other @ StorageError::Io(_) => panic!("unexpected error: {other:?}"),
+            other => panic!("unexpected error: {other:?}"),
         }
 
         std::fs::remove_file(path).expect("temp key file should be removable");

server/crates/arbiter-client/src/transport.rs

@@ -1,17 +1,18 @@
-use arbiter_proto::proto::client::{ClientRequest, ClientResponse};
+use arbiter_proto::proto::{
-
+    client::{ClientRequest, ClientResponse},
+};
 use std::sync::atomic::{AtomicI32, Ordering};
 use tokio::sync::mpsc;
 
-pub const BUFFER_LENGTH: usize = 16;
+pub(crate) const BUFFER_LENGTH: usize = 16;
 static NEXT_REQUEST_ID: AtomicI32 = AtomicI32::new(1);
 
-pub fn next_request_id() -> i32 {
+pub(crate) fn next_request_id() -> i32 {
     NEXT_REQUEST_ID.fetch_add(1, Ordering::Relaxed)
 }
 
 #[derive(Debug, thiserror::Error)]
-pub enum ClientSignError {
+pub(crate) enum ClientSignError {
     #[error("Transport channel closed")]
     ChannelClosed,
 
@@ -19,23 +20,29 @@ pub enum ClientSignError {
     ConnectionClosed,
 }
 
-pub struct ClientTransport {
+pub(crate) struct ClientTransport {
     pub(crate) sender: mpsc::Sender<ClientRequest>,
     pub(crate) receiver: tonic::Streaming<ClientResponse>,
 }
 
 impl ClientTransport {
-    pub(crate) async fn send(&mut self, request: ClientRequest) -> Result<(), ClientSignError> {
+    pub(crate) async fn send(
+        &mut self,
+        request: ClientRequest,
+    ) -> std::result::Result<(), ClientSignError> {
         self.sender
             .send(request)
             .await
             .map_err(|_| ClientSignError::ChannelClosed)
     }
 
-    pub(crate) async fn recv(&mut self) -> Result<ClientResponse, ClientSignError> {
+    pub(crate) async fn recv(
+        &mut self,
+    ) -> std::result::Result<ClientResponse, ClientSignError> {
         match self.receiver.message().await {
             Ok(Some(resp)) => Ok(resp),
-            Ok(None) | Err(_) => Err(ClientSignError::ConnectionClosed),
+            Ok(None) => Err(ClientSignError::ConnectionClosed),
+            Err(_) => Err(ClientSignError::ConnectionClosed),
         }
     }
 }

server/crates/arbiter-client/src/wallets/evm.rs

@@ -1,21 +1,3 @@
-use crate::transport::{ClientTransport, next_request_id};
-use arbiter_proto::proto::{
-    client::{
-        ClientRequest,
-        client_request::Payload as ClientRequestPayload,
-        client_response::Payload as ClientResponsePayload,
-        evm::{
-            self as proto_evm, request::Payload as EvmRequestPayload,
-            response::Payload as EvmResponsePayload,
-        },
-    },
-    evm::{
-        EvmSignTransactionRequest,
-        evm_sign_transaction_response::Result as EvmSignTransactionResult,
-    },
-    shared::evm::TransactionEvalError,
-};
-
 use alloy::{
     consensus::SignableTransaction,
     network::TxSigner,
@@ -26,30 +8,7 @@ use async_trait::async_trait;
 use std::sync::Arc;
 use tokio::sync::Mutex;
 
-/// A typed error payload returned by [`ArbiterEvmWallet`] transaction signing.
+use crate::transport::ClientTransport;
-///
-/// This is wrapped into `alloy::signers::Error::Other`, so consumers can downcast by [`TryFrom`] and
-/// interpret the concrete policy evaluation failure instead of parsing strings.
-#[derive(Debug, thiserror::Error)]
-#[non_exhaustive]
-pub enum ArbiterEvmSignTransactionError {
-    #[error("transaction rejected by policy: {0:?}")]
-    PolicyEval(TransactionEvalError),
-}
-
-impl<'a> TryFrom<&'a Error> for &'a ArbiterEvmSignTransactionError {
-    type Error = ();
-
-    fn try_from(value: &'a Error) -> Result<Self, Self::Error> {
-        if let Error::Other(inner) = value
-            && let Some(eval_error) = inner.downcast_ref()
-        {
-            Ok(eval_error)
-        } else {
-            Err(())
-        }
-    }
-}
 
 pub struct ArbiterEvmWallet {
     transport: Arc<Mutex<ClientTransport>>,
@@ -58,11 +17,7 @@ pub struct ArbiterEvmWallet {
 }
 
 impl ArbiterEvmWallet {
-    #[expect(
+    pub(crate) fn new(transport: Arc<Mutex<ClientTransport>>, address: Address) -> Self {
-        dead_code,
-        reason = "new will be used in future methods for creating wallets with different parameters"
-    )]
-    pub(crate) const fn new(transport: Arc<Mutex<ClientTransport>>, address: Address) -> Self {
         Self {
             transport,
             address,
@@ -70,12 +25,11 @@ impl ArbiterEvmWallet {
         }
     }
 
-    pub const fn address(&self) -> Address {
+    pub fn address(&self) -> Address {
         self.address
     }
 
-    #[must_use]
+    pub fn with_chain_id(mut self, chain_id: ChainId) -> Self {
-    pub const fn with_chain_id(mut self, chain_id: ChainId) -> Self {
         self.chain_id = Some(chain_id);
         self
     }
@@ -125,73 +79,11 @@ impl TxSigner<Signature> for ArbiterEvmWallet {
         &self,
         tx: &mut dyn SignableTransaction<Signature>,
     ) -> Result<Signature> {
+        let _transport = self.transport.lock().await;
         self.validate_chain_id(tx)?;
 
-        let mut transport = self.transport.lock().await;
+        Err(Error::other(
-        let request_id = next_request_id();
+            "transaction signing is not supported by current arbiter.client protocol",
-        let rlp_transaction = tx.encoded_for_signing();
+        ))
-
-        transport
-            .send(ClientRequest {
-                request_id,
-                payload: Some(ClientRequestPayload::Evm(proto_evm::Request {
-                    payload: Some(EvmRequestPayload::SignTransaction(
-                        EvmSignTransactionRequest {
-                            wallet_address: self.address.to_vec(),
-                            rlp_transaction,
-                        },
-                    )),
-                })),
-            })
-            .await
-            .map_err(|_| Error::other("failed to send evm sign transaction request"))?;
-
-        let response = transport
-            .recv()
-            .await
-            .map_err(|_| Error::other("failed to receive evm sign transaction response"))?;
-        drop(transport);
-
-        if response.request_id != Some(request_id) {
-            return Err(Error::other(
-                "received mismatched response id for evm sign transaction",
-            ));
-        }
-
-        let payload = response
-            .payload
-            .ok_or_else(|| Error::other("missing evm sign transaction response payload"))?;
-
-        let ClientResponsePayload::Evm(proto_evm::Response {
-            payload: Some(payload),
-        }) = payload
-        else {
-            return Err(Error::other(
-                "unexpected response payload for evm sign transaction request",
-            ));
-        };
-
-        let EvmResponsePayload::SignTransaction(response) = payload else {
-            return Err(Error::other(
-                "unexpected evm response payload for sign transaction request",
-            ));
-        };
-
-        let result = response
-            .result
-            .ok_or_else(|| Error::other("missing evm sign transaction result"))?;
-
-        match result {
-            EvmSignTransactionResult::Signature(signature) => {
-                Signature::try_from(signature.as_slice())
-                    .map_err(|_| Error::other("invalid signature returned by server"))
-            }
-            EvmSignTransactionResult::EvalError(eval_error) => Err(Error::other(
-                ArbiterEvmSignTransactionError::PolicyEval(eval_error),
-            )),
-            EvmSignTransactionResult::Error(code) => Err(Error::other(format!(
-                "server failed to sign transaction with error code {code}"
-            ))),
-        }
     }
 }

server/crates/arbiter-crypto/.gitignore

@@ -1 +0,0 @@
-/target

server/crates/arbiter-crypto/Cargo.toml

@@ -1,22 +0,0 @@
-[package]
-name = "arbiter-crypto"
-version = "0.1.0"
-edition = "2024"
-
-[dependencies]
-ml-dsa = {workspace = true, optional = true }
-rand = {workspace = true, optional = true}
-memsafe = {version = "0.4.0", optional = true}
-hmac.workspace = true
-alloy.workspace = true
-x-wing = { version = "0.1.0-rc.0", features = ["zeroize"] }
-chrono.workspace = true
-thiserror.workspace = true
-
-[lints]
-workspace = true
-
-[features]
-default = ["authn", "safecell"]
-authn = ["dep:ml-dsa", "dep:rand"]
-safecell = ["dep:memsafe"]

server/crates/arbiter-crypto/src/authn/mod.rs

@@ -1,2 +0,0 @@
-pub mod v1;
-pub use v1::*;

server/crates/arbiter-crypto/src/authn/v1.rs

@@ -1,252 +0,0 @@
-use chrono::{DateTime, Utc};
-use hmac::digest::Digest;
-use ml_dsa::{
-    EncodedVerifyingKey, Error, KeyGen, MlDsa87, Seed, Signature as MlDsaSignature,
-    SigningKey as MlDsaSigningKey, VerifyingKey as MlDsaVerifyingKey, signature::Keypair as _,
-};
-use rand::RngExt;
-
-pub static CLIENT_CONTEXT: &[u8] = b"arbiter_client";
-pub static OPERATOR_CONTEXT: &[u8] = b"arbiter_operator";
-
-const NONCE_SIZE: usize = 32;
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, thiserror::Error)]
-#[error("invalid length: expected {expected} bytes, got {actual} bytes")]
-pub struct InvalidLength {
-    pub expected: usize,
-    pub actual: usize,
-}
-
-#[derive(Debug, Clone)]
-pub struct AuthChallenge {
-    pub nonce: [u8; NONCE_SIZE],
-    pub timestamp: DateTime<Utc>,
-}
-
-impl AuthChallenge {
-    pub fn generate(rng: &mut impl rand::CryptoRng) -> Self {
-        let timestamp = Utc::now();
-        let nonce = {
-            let mut array = [0; NONCE_SIZE];
-            rng.fill(&mut array);
-            array
-        };
-
-        Self { nonce, timestamp }
-    }
-
-    pub fn format(&self) -> Vec<u8> {
-        {
-            let mut buffer = Vec::from(self.nonce);
-
-            let stamp = self
-                .timestamp
-                .timestamp_nanos_opt()
-                .expect("We would be long dead by the time this triggers :)");
-            buffer.extend_from_slice(stamp.to_be_bytes().as_slice());
-
-            buffer
-        }
-    }
-
-    pub fn from_parts(nonce: &[u8], timestamp: i64) -> Result<Self, InvalidLength> {
-        let random_nonce = nonce.as_array().ok_or(InvalidLength {
-            expected: NONCE_SIZE,
-            actual: nonce.len(),
-        })?;
-        Ok(Self {
-            nonce: *random_nonce,
-            timestamp: DateTime::from_timestamp_nanos(timestamp),
-        })
-    }
-}
-
-pub type KeyParams = MlDsa87;
-
-#[derive(Clone, Debug, PartialEq)]
-pub struct PublicKey(Box<MlDsaVerifyingKey<KeyParams>>);
-
-impl crate::hashing::Hashable for PublicKey {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.to_bytes());
-    }
-}
-
-#[derive(Clone, Debug, PartialEq)]
-pub struct Signature(Box<MlDsaSignature<KeyParams>>);
-
-#[derive(Debug)]
-pub struct SigningKey(Box<MlDsaSigningKey<KeyParams>>);
-
-impl PublicKey {
-    pub fn to_bytes(&self) -> Vec<u8> {
-        self.0.encode().0.to_vec()
-    }
-
-    #[must_use]
-    pub fn verify(&self, challenge: &AuthChallenge, context: &[u8], signature: &Signature) -> bool {
-        let challenge = challenge.format();
-        self.0
-            .verify_with_context(&challenge, context, &signature.0)
-    }
-}
-
-impl Signature {
-    pub fn to_bytes(&self) -> Vec<u8> {
-        self.0.encode().0.to_vec()
-    }
-}
-
-impl SigningKey {
-    pub fn generate() -> Self {
-        Self(Box::new(KeyParams::key_gen(&mut rand::rng())))
-    }
-
-    pub fn from_seed(seed: [u8; 32]) -> Self {
-        Self(Box::new(KeyParams::from_seed(&Seed::from(seed))))
-    }
-
-    pub fn to_seed(&self) -> [u8; 32] {
-        self.0.to_seed().into()
-    }
-
-    pub fn public_key(&self) -> PublicKey {
-        self.0.verifying_key().into()
-    }
-
-    pub fn sign_message(&self, message: &[u8], context: &[u8]) -> Result<Signature, Error> {
-        self.0
-            .signing_key()
-            .sign_deterministic(message, context)
-            .map(Into::into)
-    }
-
-    pub fn sign_challenge(
-        &self,
-        challenge: &AuthChallenge,
-        context: &[u8],
-    ) -> Result<Signature, Error> {
-        let challenge = challenge.format();
-
-        self.sign_message(&challenge, context)
-    }
-}
-
-impl From<MlDsaVerifyingKey<KeyParams>> for PublicKey {
-    fn from(value: MlDsaVerifyingKey<KeyParams>) -> Self {
-        Self(Box::new(value))
-    }
-}
-
-impl From<MlDsaSignature<KeyParams>> for Signature {
-    fn from(value: MlDsaSignature<KeyParams>) -> Self {
-        Self(Box::new(value))
-    }
-}
-
-impl From<MlDsaSigningKey<KeyParams>> for SigningKey {
-    fn from(value: MlDsaSigningKey<KeyParams>) -> Self {
-        Self(Box::new(value))
-    }
-}
-
-impl TryFrom<Vec<u8>> for PublicKey {
-    type Error = ();
-
-    fn try_from(value: Vec<u8>) -> Result<Self, Self::Error> {
-        Self::try_from(value.as_slice())
-    }
-}
-
-impl TryFrom<&'_ [u8]> for PublicKey {
-    type Error = ();
-
-    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
-        let encoded = EncodedVerifyingKey::<KeyParams>::try_from(value).map_err(|_| ())?;
-        Ok(Self(Box::new(MlDsaVerifyingKey::decode(&encoded))))
-    }
-}
-
-impl TryFrom<Vec<u8>> for Signature {
-    type Error = ();
-
-    fn try_from(value: Vec<u8>) -> Result<Self, Self::Error> {
-        Self::try_from(value.as_slice())
-    }
-}
-
-impl TryFrom<&'_ [u8]> for Signature {
-    type Error = ();
-
-    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
-        MlDsaSignature::try_from(value)
-            .map(|sig| Self(Box::new(sig)))
-            .map_err(|_| ())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use ml_dsa::{KeyGen, MlDsa87, signature::Keypair as _};
-
-    use crate::authn::AuthChallenge;
-
-    use super::{CLIENT_CONTEXT, PublicKey, Signature, SigningKey, OPERATOR_CONTEXT};
-
-    #[test]
-    fn public_key_round_trip_decodes() {
-        let key = MlDsa87::key_gen(&mut rand::rng());
-        let encoded = PublicKey::from(key.verifying_key()).to_bytes();
-
-        let decoded = PublicKey::try_from(encoded.as_slice()).expect("public key should decode");
-
-        assert_eq!(decoded, PublicKey::from(key.verifying_key()));
-    }
-
-    #[test]
-    fn signature_round_trip_decodes() {
-        let key = SigningKey::generate();
-        let signature = key
-            .sign_message(b"challenge", CLIENT_CONTEXT)
-            .expect("signature should be created");
-
-        let decoded =
-            Signature::try_from(signature.to_bytes().as_slice()).expect("signature should decode");
-
-        assert_eq!(decoded, signature);
-    }
-
-    #[test]
-    fn challenge_verification_uses_context_and_canonical_key_bytes() {
-        let key = SigningKey::generate();
-        let public_key = key.public_key();
-        let challenge = AuthChallenge::generate(&mut rand::rng());
-        let signature = key
-            .sign_challenge(&challenge, CLIENT_CONTEXT)
-            .expect("signature should be created");
-
-        assert!(public_key.verify(&challenge, CLIENT_CONTEXT, &signature));
-        assert!(!public_key.verify(&challenge, OPERATOR_CONTEXT, &signature));
-    }
-
-    #[test]
-    fn signing_key_round_trip_seed_preserves_public_key_and_signing() {
-        let original = SigningKey::generate();
-        let restored = SigningKey::from_seed(original.to_seed());
-
-        assert_eq!(restored.public_key(), original.public_key());
-
-        let challenge = AuthChallenge::generate(&mut rand::rng());
-
-        let signature = restored
-            .sign_challenge(&challenge, CLIENT_CONTEXT)
-            .expect("signature should be created");
-
-        assert!(
-            restored
-                .public_key()
-                .verify(&challenge, CLIENT_CONTEXT, &signature)
-        );
-    }
-}

server/crates/arbiter-crypto/src/hashing.rs

@@ -1,112 +0,0 @@
-use std::collections::HashSet;
-
-pub use hmac::digest::Digest;
-
-/// Deterministically hash a value by feeding its fields into the hasher in a consistent order.
-#[diagnostic::on_unimplemented(
-    note = "for local types consider adding `#[derive(arbiter_macros::Hashable)]` to your `{Self}` type",
-    note = "for types from other crates check whether the crate offers a `Hashable` implementation"
-)]
-pub trait Hashable {
-    fn hash<H: Digest>(&self, hasher: &mut H);
-}
-
-macro_rules! impl_numeric {
-    ($($t:ty),*) => {
-        $(
-            impl Hashable for $t {
-                fn hash<H: Digest>(&self, hasher: &mut H) {
-                    hasher.update(&self.to_be_bytes());
-                }
-            }
-        )*
-    };
-}
-
-impl_numeric!(u8, u16, u32, u64, i8, i16, i32, i64);
-
-impl Hashable for &[u8] {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self);
-    }
-}
-
-impl Hashable for String {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.as_bytes());
-    }
-}
-
-impl<T: Hashable + PartialOrd> Hashable for Vec<T> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        let ref_sorted = {
-            let mut sorted = self.iter().collect::<Vec<_>>();
-            sorted.sort_by(|a, b| a.partial_cmp(b).unwrap());
-            sorted
-        };
-        for item in ref_sorted {
-            item.hash(hasher);
-        }
-    }
-}
-
-impl<T: Hashable + PartialOrd, S: std::hash::BuildHasher> Hashable for HashSet<T, S> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        let ref_sorted = {
-            let mut sorted = self.iter().collect::<Vec<_>>();
-            sorted.sort_by(|a, b| a.partial_cmp(b).unwrap());
-            sorted
-        };
-        for item in ref_sorted {
-            item.hash(hasher);
-        }
-    }
-}
-
-impl<T: Hashable> Hashable for Option<T> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        match self {
-            Some(value) => {
-                hasher.update([1]);
-                value.hash(hasher);
-            }
-            None => hasher.update([0]),
-        }
-    }
-}
-
-impl<T: Hashable> Hashable for Box<T> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        self.as_ref().hash(hasher);
-    }
-}
-
-impl<T: Hashable> Hashable for &T {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        (*self).hash(hasher);
-    }
-}
-
-impl Hashable for alloy::primitives::Address {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.as_slice());
-    }
-}
-
-impl Hashable for alloy::primitives::U256 {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.to_be_bytes::<32>());
-    }
-}
-
-impl Hashable for chrono::Duration {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.num_seconds().to_be_bytes());
-    }
-}
-
-impl Hashable for chrono::DateTime<chrono::Utc> {
-    fn hash<H: Digest>(&self, hasher: &mut H) {
-        hasher.update(self.timestamp_millis().to_be_bytes());
-    }
-}

server/crates/arbiter-crypto/src/lib.rs

@@ -1,7 +0,0 @@
-#[cfg(feature = "authn")]
-pub mod authn;
-pub mod hashing;
-#[cfg(feature = "safecell")]
-pub mod safecell;
-
-pub use x_wing;

server/crates/arbiter-macros/Cargo.toml

@@ -1,18 +0,0 @@
-[package]
-name = "arbiter-macros"
-version = "0.1.0"
-edition = "2024"
-
-[lib]
-proc-macro = true
-
-[dependencies]
-proc-macro2 = "1.0"
-quote = "1.0"
-syn = { version = "2.0", features = ["derive", "fold", "full", "visit-mut"] }
-
-[dev-dependencies]
-arbiter-crypto = { path = "../arbiter-crypto" }
-
-[lints]
-workspace = true

server/crates/arbiter-macros/src/hashable.rs

@@ -1,131 +0,0 @@
-use crate::utils::{HASHABLE_TRAIT_PATH, HMAC_DIGEST_PATH};
-
-use proc_macro2::{Span, TokenStream, TokenTree};
-use quote::quote;
-use syn::{DataStruct, DeriveInput, Fields, Generics, Index, parse_quote, spanned::Spanned};
-
-pub(crate) fn derive(input: &DeriveInput) -> TokenStream {
-    match &input.data {
-        syn::Data::Struct(struct_data) => hashable_struct(input, struct_data),
-        syn::Data::Enum(_) => {
-            syn::Error::new_spanned(input, "Hashable can currently be derived only for structs")
-                .to_compile_error()
-        }
-        syn::Data::Union(_) => {
-            syn::Error::new_spanned(input, "Hashable cannot be derived for unions")
-                .to_compile_error()
-        }
-    }
-}
-
-fn hashable_struct(input: &DeriveInput, struct_data: &DataStruct) -> TokenStream {
-    let ident = &input.ident;
-    let hashable_trait = HASHABLE_TRAIT_PATH.to_path();
-    let hmac_digest = HMAC_DIGEST_PATH.to_path();
-    let generics = add_hashable_bounds(input.generics.clone(), &hashable_trait);
-    let field_accesses = collect_field_accesses(struct_data);
-    let hash_calls = build_hash_calls(&field_accesses, &hashable_trait);
-
-    let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
-
-    quote! {
-        #[automatically_derived]
-        impl #impl_generics #hashable_trait for #ident #ty_generics #where_clause {
-            fn hash<H: #hmac_digest>(&self, hasher: &mut H) {
-                #(#hash_calls)*
-            }
-        }
-    }
-}
-
-fn add_hashable_bounds(mut generics: Generics, hashable_trait: &syn::Path) -> Generics {
-    for type_param in generics.type_params_mut() {
-        type_param.bounds.push(parse_quote!(#hashable_trait));
-    }
-
-    generics
-}
-
-struct FieldAccess {
-    access: TokenStream,
-    span: Span,
-}
-
-fn collect_field_accesses(struct_data: &DataStruct) -> Vec<FieldAccess> {
-    match &struct_data.fields {
-        Fields::Named(fields) => {
-            // Keep deterministic alphabetical order for named fields.
-            // Do not remove this sort, because it keeps hash output stable regardless of source order.
-            let mut named_fields = fields
-                .named
-                .iter()
-                .map(|field| {
-                    let name = field
-                        .ident
-                        .as_ref()
-                        .expect("Fields::Named(fields) must have names")
-                        .clone();
-                    (name.to_string(), name)
-                })
-                .collect::<Vec<_>>();
-
-            named_fields.sort_by(|a, b| a.0.cmp(&b.0));
-
-            named_fields
-                .into_iter()
-                .map(|(_, name)| FieldAccess {
-                    access: quote! { #name },
-                    span: name.span(),
-                })
-                .collect()
-        }
-        Fields::Unnamed(fields) => fields
-            .unnamed
-            .iter()
-            .enumerate()
-            .map(|(i, field)| FieldAccess {
-                access: {
-                    let index = Index::from(i);
-                    quote! { #index }
-                },
-                span: field.ty.span(),
-            })
-            .collect(),
-        Fields::Unit => Vec::new(),
-    }
-}
-
-fn build_hash_calls(
-    field_accesses: &[FieldAccess],
-    hashable_trait: &syn::Path,
-) -> Vec<TokenStream> {
-    field_accesses
-        .iter()
-        .map(|field| {
-            let access = &field.access;
-            let call = quote! {
-                #hashable_trait::hash(&self.#access, hasher);
-            };
-
-            respan(call, field.span)
-        })
-        .collect()
-}
-
-/// Recursively set span on all tokens, including interpolated ones.
-fn respan(tokens: TokenStream, span: Span) -> TokenStream {
-    tokens
-        .into_iter()
-        .map(|tt| match tt {
-            TokenTree::Group(g) => {
-                let mut new = proc_macro2::Group::new(g.delimiter(), respan(g.stream(), span));
-                new.set_span(span);
-                TokenTree::Group(new)
-            }
-            mut other => {
-                other.set_span(span);
-                other
-            }
-        })
-        .collect()
-}

server/crates/arbiter-macros/src/lib.rs

@@ -1,10 +0,0 @@
-use syn::{DeriveInput, parse_macro_input};
-
-mod hashable;
-mod utils;
-
-#[proc_macro_derive(Hashable)]
-pub fn derive_hashable(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
-    let input = parse_macro_input!(input as DeriveInput);
-    hashable::derive(&input).into()
-}

server/crates/arbiter-macros/src/utils.rs

@@ -1,24 +0,0 @@
-pub(crate) struct ToPath(pub &'static str);
-
-impl ToPath {
-    pub(crate) fn to_path(&self) -> syn::Path {
-        syn::parse_str(self.0).expect("Invalid path")
-    }
-}
-
-macro_rules! ensure_path {
-    ($path:path as $name:ident) => {
-        const _: () = {
-            #[cfg(test)]
-            #[expect(
-                unused_imports,
-                reason = "Ensures the path is valid and will cause a compile error if not"
-            )]
-            use $path as _;
-        };
-        pub(crate) const $name: ToPath = ToPath(stringify!($path));
-    };
-}
-
-ensure_path!(::arbiter_crypto::hashing::Hashable as HASHABLE_TRAIT_PATH);
-ensure_path!(::arbiter_crypto::hashing::Digest as HMAC_DIGEST_PATH);

server/crates/arbiter-proto/Cargo.toml

@@ -11,13 +11,13 @@ tokio.workspace = true
 futures.workspace = true
 hex = "0.4.3"
 tonic-prost = "0.14.5"
-prost.workspace = true
+prost = "0.14.3"
 kameo.workspace = true
 url = "2.5.8"
 miette.workspace = true
 thiserror.workspace = true
 rustls-pki-types.workspace = true
-base64.workspace = true
+base64 = "0.22.1"
 prost-types.workspace = true
 tracing.workspace = true
 async-trait.workspace = true

server/crates/arbiter-proto/build.rs

@@ -10,7 +10,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         .compile_protos(
             &[
                 format!("{}/arbiter.proto", PROTOBUF_DIR),
-                format!("{}/operator.proto", PROTOBUF_DIR),
+                format!("{}/user_agent.proto", PROTOBUF_DIR),
                 format!("{}/client.proto", PROTOBUF_DIR),
                 format!("{}/evm.proto", PROTOBUF_DIR),
             ],

server/crates/arbiter-proto/src/lib.rs

@@ -1,59 +1,21 @@
 pub mod transport;
 pub mod url;
 
+use base64::{Engine, prelude::BASE64_STANDARD};
+use std::{
+    path::PathBuf,
+    sync::{LazyLock, RwLock},
+};
+
 pub mod proto {
     tonic::include_proto!("arbiter");
 
-    pub mod shared {
+    pub mod user_agent {
-        tonic::include_proto!("arbiter.shared");
+        tonic::include_proto!("arbiter.user_agent");
-
-        pub mod evm {
-            tonic::include_proto!("arbiter.shared.evm");
-        }
-    }
-
-    pub mod operator {
-        tonic::include_proto!("arbiter.operator");
-
-        pub mod auth {
-            tonic::include_proto!("arbiter.operator.auth");
-        }
-
-        pub mod evm {
-            tonic::include_proto!("arbiter.operator.evm");
-        }
-
-        pub mod sdk_client {
-            tonic::include_proto!("arbiter.operator.sdk_client");
-        }
-
-        pub mod vault {
-            tonic::include_proto!("arbiter.operator.vault");
-
-            pub mod bootstrap {
-                tonic::include_proto!("arbiter.operator.vault.bootstrap");
-            }
-
-            pub mod unseal {
-                tonic::include_proto!("arbiter.operator.vault.unseal");
-            }
-        }
     }
 
     pub mod client {
         tonic::include_proto!("arbiter.client");
-
-        pub mod auth {
-            tonic::include_proto!("arbiter.client.auth");
-        }
-
-        pub mod evm {
-            tonic::include_proto!("arbiter.client.evm");
-        }
-
-        pub mod vault {
-            tonic::include_proto!("arbiter.client.vault");
-        }
     }
 
     pub mod evm {
@@ -69,8 +31,27 @@ pub struct ClientMetadata {
 }
 
 pub static BOOTSTRAP_PATH: &str = "bootstrap_token";
+pub const DEFAULT_SERVER_PORT: u16 = 50051;
+static HOME_OVERRIDE: LazyLock<RwLock<Option<PathBuf>>> = LazyLock::new(|| RwLock::new(None));
+
+pub fn set_home_path_override(path: Option<PathBuf>) -> Result<(), std::io::Error> {
+    let mut lock = HOME_OVERRIDE
+        .write()
+        .map_err(|_| std::io::Error::other("home path override lock poisoned"))?;
+    *lock = path;
+    Ok(())
+}
 
 pub fn home_path() -> Result<std::path::PathBuf, std::io::Error> {
+    if let Some(path) = HOME_OVERRIDE
+        .read()
+        .map_err(|_| std::io::Error::other("home path override lock poisoned"))?
+        .clone()
+    {
+        std::fs::create_dir_all(&path)?;
+        return Ok(path);
+    }
+
     static ARBITER_HOME: &str = ".arbiter";
     let home_dir = std::env::home_dir().ok_or(std::io::Error::new(
         std::io::ErrorKind::PermissionDenied,
@@ -82,3 +63,8 @@ pub fn home_path() -> Result<std::path::PathBuf, std::io::Error> {
 
     Ok(arbiter_home)
 }
+
+pub fn format_challenge(nonce: i32, pubkey: &[u8]) -> Vec<u8> {
+    let concat_form = format!("{}:{}", nonce, BASE64_STANDARD.encode(pubkey));
+    concat_form.into_bytes()
+}

server/crates/arbiter-proto/src/transport.rs

@@ -54,10 +54,11 @@
 //!   as a closed outbound channel.
 //! - [`Bi::recv`] returns `None` when the underlying transport closes.
 //! - Message translation is intentionally out of scope for this module.
-use async_trait::async_trait;
+
-use kameo::{error::Infallible, prelude::*};
 use std::marker::PhantomData;
 
+use async_trait::async_trait;
+
 /// Errors returned by transport adapters implementing [`Bi`].
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
@@ -105,36 +106,6 @@ pub trait Receiver<Inbound>: Send + Sync {
 /// any built-in correlation mechanism between inbound and outbound items.
 pub trait Bi<Inbound, Outbound>: Sender<Outbound> + Receiver<Inbound> + Send + Sync {}
 
-#[async_trait]
-impl<T, Outbound> Sender<Outbound> for &mut T
-where
-    T: Sender<Outbound> + ?Sized,
-    Outbound: Send + 'static,
-{
-    async fn send(&mut self, item: Outbound) -> Result<(), Error> {
-        (**self).send(item).await
-    }
-}
-
-#[async_trait]
-impl<T, Inbound> Receiver<Inbound> for &mut T
-where
-    T: Receiver<Inbound> + ?Sized,
-    Inbound: Send + 'static,
-{
-    async fn recv(&mut self) -> Option<Inbound> {
-        (**self).recv().await
-    }
-}
-
-impl<T, Inbound, Outbound> Bi<Inbound, Outbound> for &mut T
-where
-    T: Bi<Inbound, Outbound> + ?Sized,
-    Inbound: Send + 'static,
-    Outbound: Send + 'static,
-{
-}
-
 pub trait SplittableBi<Inbound, Outbound>: Bi<Inbound, Outbound> {
     type Sender: Sender<Outbound>;
     type Receiver: Receiver<Inbound>;
@@ -190,29 +161,3 @@ where
 }
 
 pub mod grpc;
-
-#[derive(thiserror::Error, Debug)]
-pub enum ForwardError<I> {
-    #[error("Transport error: {0}")]
-    Transport(#[from] Error),
-    #[error("Actor delivery error: {0}")]
-    Actor(SendError<I>),
-}
-
-pub async fn forward_to_actor<Transport, Inbound, Outbound, Handler>(
-    transport: &mut Transport,
-    actor: &ActorRef<Handler>,
-) -> Result<(), ForwardError<Inbound>>
-where
-    Transport: Bi<Inbound, <Outbound as Reply>::Ok>,
-    Handler: Actor + Message<Inbound, Reply = Outbound>,
-    Inbound: Send + 'static,
-    Outbound: Send + 'static + Reply<Error = Infallible>, // `Infallible` to enforce contract that `Outbound` carries handler-level error
-{
-    while let Some(request) = transport.recv().await {
-        let resp = actor.ask(request).await.map_err(ForwardError::Actor)?;
-        transport.send(resp).await?
-    }
-
-    Err(Error::ChannelClosed.into())
-}

server/crates/arbiter-proto/src/transport/grpc.rs

@@ -1,10 +1,10 @@
-use super::{Bi, Receiver, Sender};
-
 use async_trait::async_trait;
 use futures::StreamExt;
 use tokio::sync::mpsc;
 use tokio_stream::wrappers::ReceiverStream;
 
+use super::{Bi, Receiver, Sender};
+
 pub struct GrpcSender<Outbound> {
     tx: mpsc::Sender<Result<Outbound, tonic::Status>>,
 }

server/crates/arbiter-proto/src/url.rs

@@ -1,11 +1,13 @@
+use std::fmt::Display;
+
 use base64::{Engine as _, prelude::BASE64_URL_SAFE};
 use rustls_pki_types::CertificateDer;
-use std::fmt::Display;
 
 const ARBITER_URL_SCHEME: &str = "arbiter";
 const CERT_QUERY_KEY: &str = "cert";
 const BOOTSTRAP_TOKEN_QUERY_KEY: &str = "bootstrap_token";
 
+
 #[derive(Debug, Clone)]
 pub struct ArbiterUrl {
     pub host: String,
@@ -104,7 +106,7 @@ mod tests {
 
     #[rstest]
 
-    fn parsing_correctness(
+    fn test_parsing_correctness(
         #[values("127.0.0.1", "localhost", "192.168.1.1", "some.domain.com")] host: &str,
 
         #[values(None, Some("token123".to_string()))] bootstrap_token: Option<String>,

server/crates/arbiter-server/Cargo.toml

@@ -16,9 +16,8 @@ diesel-async = { version = "0.8.0", features = [
     "sqlite",
     "tokio",
 ] }
+ed25519-dalek.workspace = true
 arbiter-proto.path = "../arbiter-proto"
-arbiter-crypto.path = "../arbiter-crypto"
-arbiter-macros.path = "../arbiter-macros"
 tracing.workspace = true
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 tonic.workspace = true
@@ -26,6 +25,7 @@ tonic.features = ["tls-aws-lc"]
 tokio.workspace = true
 rustls.workspace = true
 smlang.workspace = true
+miette.workspace = true
 thiserror.workspace = true
 fatality = "0.1.1"
 diesel_migrations = { version = "2.3.1", features = ["sqlite"] }
@@ -37,32 +37,27 @@ dashmap = "6.1.0"
 rand.workspace = true
 rcgen.workspace = true
 chrono.workspace = true
+memsafe = "0.4.0"
 zeroize = { version = "1.8.2", features = ["std", "simd"] }
 kameo.workspace = true
+x25519-dalek.workspace = true
 chacha20poly1305 = { version = "0.10.1", features = ["std"] }
 argon2 = { version = "0.5.3", features = ["zeroize"] }
 restructed = "0.2.2"
 strum = { version = "0.28.0", features = ["derive"] }
 pem = "3.0.6"
+k256.workspace = true
+rsa.workspace = true
 sha2.workspace = true
-hmac.workspace = true
 spki.workspace = true
 alloy.workspace = true
 prost-types.workspace = true
-prost.workspace = true
 arbiter-tokens-registry.path = "../arbiter-tokens-registry"
-anyhow = "1.0.102"
+clap = { version = "4.6", features = ["derive"] }
-serde_with = "3.18.0"
-mutants.workspace = true
-subtle = "2.6.1"
-ml-dsa.workspace = true
-ed25519-dalek.workspace = true
-x25519-dalek.workspace = true
-k256.workspace = true
-kameo_actors.workspace = true
 
 [dev-dependencies]
-insta = "1.47.2"
+insta = "1.46.3"
-proptest = "1.11.0"
-rstest.workspace = true
 test-log = { version = "0.2", default-features = false, features = ["trace"] }
+
+[target.'cfg(windows)'.dependencies]
+windows-service = "0.8"

server/crates/arbiter-server/migrations/2026-02-14-171124-0000_init/up.sql

@@ -43,13 +43,15 @@ create table if not exists arbiter_settings (
 insert into arbiter_settings (id) values (1) on conflict do nothing;
 -- ensure singleton row exists
 
-create table if not exists operator_client (
+create table if not exists useragent_client (
     id integer not null primary key,
+    nonce integer not null default(1), -- used for auth challenge
     public_key blob not null,
+    key_type integer not null default(1), -- 1=Ed25519, 2=ECDSA(secp256k1)
     created_at integer not null default(unixepoch ('now')),
     updated_at integer not null default(unixepoch ('now'))
 ) STRICT;
-create unique index if not exists uniq_operator_client_public_key on operator_client (public_key);
+create unique index if not exists uniq_useragent_client_public_key on useragent_client (public_key, key_type);
 
 create table if not exists client_metadata (
     id integer not null primary key,
@@ -71,6 +73,7 @@ create unique index if not exists uniq_metadata_binding_client on client_metadat
 
 create table if not exists program_client (
     id integer not null primary key,
+    nonce integer not null default(1), -- used for auth challenge
     public_key blob not null,
     metadata_id integer not null references client_metadata (id) on delete cascade,
     created_at integer not null default(unixepoch ('now')),
@@ -188,19 +191,3 @@ create table if not exists evm_ether_transfer_grant_target (
 ) STRICT;
 
 create unique index if not exists uniq_ether_transfer_target on evm_ether_transfer_grant_target (grant_id, address);
-
--- ===============================
--- Integrity Envelopes
--- ===============================
-create table if not exists integrity_envelope (
-    id integer not null primary key,
-    entity_kind text not null,
-    entity_id blob not null,
-    payload_version integer not null,
-    key_version integer not null,
-    mac blob not null, -- 20-byte recipient address
-    signed_at integer not null default(unixepoch ('now')),
-    created_at integer not null default(unixepoch ('now'))
-) STRICT;
-
-create unique index if not exists uniq_integrity_envelope_entity on integrity_envelope (entity_kind, entity_id);

server/crates/arbiter-server/src/actors/bootstrap.rs

@@ -1,20 +1,19 @@
-use crate::db::{self, DatabasePool, schema};
 use arbiter_proto::{BOOTSTRAP_PATH, home_path};
-
 use diesel::QueryDsl;
 use diesel_async::RunQueryDsl;
 use kameo::{Actor, messages};
+use miette::Diagnostic;
 use rand::{RngExt, distr::Alphanumeric, make_rng, rngs::StdRng};
-use subtle::ConstantTimeEq as _;
 use thiserror::Error;
 
+use crate::db::{self, DatabasePool, schema};
 const TOKEN_LENGTH: usize = 64;
 
 pub async fn generate_token() -> Result<String, std::io::Error> {
     let rng: StdRng = make_rng();
 
-    let token = rng.sample_iter(Alphanumeric).take(TOKEN_LENGTH).fold(
+    let token: String = rng.sample_iter(Alphanumeric).take(TOKEN_LENGTH).fold(
-        String::default(),
+        Default::default(),
         |mut accum, char| {
             accum += char.to_string().as_str();
             accum
@@ -26,16 +25,19 @@ pub async fn generate_token() -> Result<String, std::io::Error> {
     Ok(token)
 }
 
-#[derive(Error, Debug)]
+#[derive(Error, Debug, Diagnostic)]
 pub enum Error {
     #[error("Database error: {0}")]
+    #[diagnostic(code(arbiter_server::bootstrap::database))]
     Database(#[from] db::PoolError),
 
-    #[error("I/O error: {0}")]
-    Io(#[from] std::io::Error),
-
     #[error("Database query error: {0}")]
+    #[diagnostic(code(arbiter_server::bootstrap::database_query))]
     Query(#[from] diesel::result::Error),
+
+    #[error("I/O error: {0}")]
+    #[diagnostic(code(arbiter_server::bootstrap::io))]
+    Io(#[from] std::io::Error),
 }
 
 #[derive(Actor)]
@@ -45,14 +47,14 @@ pub struct Bootstrapper {
 
 impl Bootstrapper {
     pub async fn new(db: &DatabasePool) -> Result<Self, Error> {
-        let row_count: i64 = {
+        let mut conn = db.get().await?;
-            let mut conn = db.get().await?;
 
-            schema::operator_client::table
+        let row_count: i64 = schema::useragent_client::table
-                .count()
+            .count()
-                .get_result(&mut conn)
+            .get_result(&mut conn)
-                .await?
+            .await?;
-        };
+
+        drop(conn);
 
         let token = if row_count == 0 {
             let token = generate_token().await?;
@@ -69,13 +71,10 @@ impl Bootstrapper {
 impl Bootstrapper {
     #[message]
     pub fn is_correct_token(&self, token: String) -> bool {
-        self.token.as_ref().is_some_and(|expected| {
+        match &self.token {
-            let expected_bytes = expected.as_bytes();
+            Some(expected) => *expected == token,
-            let token_bytes = token.as_bytes();
+            None => false,
-
+        }
-            let choice = expected_bytes.ct_eq(token_bytes);
-            bool::from(choice)
-        })
     }
 
     #[message]

server/crates/arbiter-server/src/actors/client/auth.rs

@@ -1,40 +1,34 @@
-use super::{ClientConnection, ClientCredentials, ClientProfile};
-use crate::{
-    actors::{
-        GlobalActors,
-        flow_coordinator::{self, RequestClientApproval},
-        vault::Vault,
-    },
-    crypto::integrity::{self, AttestationStatus},
-    db::{
-        self,
-        models::{ProgramClientMetadata, SqliteTimestamp},
-        schema::program_client,
-    },
-};
-use arbiter_crypto::authn::{self, AuthChallenge, CLIENT_CONTEXT};
 use arbiter_proto::{
-    ClientMetadata,
+    ClientMetadata, format_challenge, transport::{Bi, expect_message}
-    transport::{Bi, expect_message},
 };
-
 use chrono::Utc;
 use diesel::{
     ExpressionMethods as _, OptionalExtension as _, QueryDsl as _, SelectableHelper as _,
     dsl::insert_into, update,
 };
 use diesel_async::RunQueryDsl as _;
-use kameo::{actor::ActorRef, error::SendError};
+use ed25519_dalek::{Signature, VerifyingKey};
+use kameo::error::SendError;
 use tracing::error;
 
+use crate::{
+    actors::{
+        client::{ClientConnection, ClientProfile},
+        flow_coordinator::{self, RequestClientApproval},
+    },
+    db::{
+        self,
+        models::{ProgramClientMetadata, SqliteTimestamp},
+        schema::program_client,
+    },
+};
+
 #[derive(thiserror::Error, Debug, Clone, PartialEq, Eq)]
 pub enum Error {
     #[error("Database pool unavailable")]
     DatabasePoolUnavailable,
     #[error("Database operation failed")]
     DatabaseOperationFailed,
-    #[error("Integrity check failed")]
-    IntegrityCheckFailed,
     #[error("Invalid challenge solution")]
     InvalidChallengeSolution,
     #[error("Client approval request failed")]
@@ -43,18 +37,11 @@ pub enum Error {
     Transport,
 }
 
-impl From<diesel::result::Error> for Error {
-    fn from(e: diesel::result::Error) -> Self {
-        error!(?e, "Database error");
-        Self::DatabaseOperationFailed
-    }
-}
-
 #[derive(thiserror::Error, Debug, Clone, PartialEq, Eq)]
 pub enum ApproveError {
     #[error("Internal error")]
     Internal,
-    #[error("Client connection denied by operators")]
+    #[error("Client connection denied by user agents")]
     Denied,
     #[error("Upstream error: {0}")]
     Upstream(flow_coordinator::ApprovalError),
@@ -63,79 +50,74 @@ pub enum ApproveError {
 #[derive(Debug, Clone)]
 pub enum Inbound {
     AuthChallengeRequest {
-        pubkey: authn::PublicKey,
+        pubkey: VerifyingKey,
         metadata: ClientMetadata,
     },
     AuthChallengeSolution {
-        signature: authn::Signature,
+        signature: Signature,
     },
 }
 
 #[derive(Debug, Clone)]
 pub enum Outbound {
-    AuthChallenge { challenge: AuthChallenge },
+    AuthChallenge { pubkey: VerifyingKey, nonce: i32 },
     AuthSuccess,
 }
 
-async fn get_client_id(
+pub struct ClientInfo {
+    pub id: i32,
+    pub current_nonce: i32,
+}
+
+/// Atomically reads and increments the nonce for a known client.
+/// Returns `None` if the pubkey is not registered.
+async fn get_client_and_nonce(
     db: &db::DatabasePool,
-    pubkey: &authn::PublicKey,
+    pubkey: &VerifyingKey,
-) -> Result<Option<i32>, Error> {
+) -> Result<Option<ClientInfo>, Error> {
-    let pubkey_bytes = pubkey.to_bytes();
+    let pubkey_bytes = pubkey.as_bytes().to_vec();
+
     let mut conn = db.get().await.map_err(|e| {
         error!(error = ?e, "Database pool error");
         Error::DatabasePoolUnavailable
     })?;
-    program_client::table
+
-        .filter(program_client::public_key.eq(&pubkey_bytes))
+    conn.exclusive_transaction(|conn| {
-        .select(program_client::id)
+        let pubkey_bytes = pubkey_bytes.clone();
-        .first::<i32>(&mut conn)
+        Box::pin(async move {
-        .await
+            let Some((client_id, current_nonce)) = program_client::table
-        .optional()
+                .filter(program_client::public_key.eq(&pubkey_bytes))
-        .map_err(|e| {
+                .select((program_client::id, program_client::nonce))
-            error!(error = ?e, "Database error");
+                .first::<(i32, i32)>(conn)
-            Error::DatabaseOperationFailed
+                .await
+                .optional()?
+            else {
+                return Result::<_, diesel::result::Error>::Ok(None);
+            };
+
+            update(program_client::table)
+                .filter(program_client::public_key.eq(&pubkey_bytes))
+                .set(program_client::nonce.eq(current_nonce + 1))
+                .execute(conn)
+                .await?;
+
+            Ok(Some(ClientInfo {
+                id: client_id,
+                current_nonce,
+            }))
         })
-}
+    })
-
-async fn verify_integrity(
-    db: &db::DatabasePool,
-    vault: &ActorRef<Vault>,
-    pubkey: &authn::PublicKey,
-) -> Result<(), Error> {
-    let mut db_conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        Error::DatabasePoolUnavailable
-    })?;
-
-    let id = get_client_id(db, pubkey).await?.ok_or_else(|| {
-        error!("Client not found during integrity verification");
-        Error::DatabaseOperationFailed
-    })?;
-
-    let attestation = integrity::verify_entity(
-        &mut db_conn,
-        vault,
-        &ClientCredentials {
-            pubkey: pubkey.clone(),
-        },
-        id,
-    )
     .await
     .map_err(|e| {
-        error!(?e, "Integrity verification failed");
+        error!(error = ?e, "Database error");
-        Error::IntegrityCheckFailed
+        Error::DatabaseOperationFailed
-    })?;
+    })
-
-    if attestation != AttestationStatus::Attested {
-        error!("Integrity attestation unavailable for client {id}");
-        return Err(Error::IntegrityCheckFailed);
-    }
-
-    Ok(())
 }
 
-async fn approve_new_client(actors: &GlobalActors, profile: ClientProfile) -> Result<(), Error> {
+async fn approve_new_client(
+    actors: &crate::actors::GlobalActors,
+    profile: ClientProfile,
+) -> Result<(), Error> {
     let result = actors
         .flow_coordinator
         .ask(RequestClientApproval { client: profile })
@@ -157,62 +139,45 @@ async fn approve_new_client(actors: &GlobalActors, profile: ClientProfile) -> Re
 
 async fn insert_client(
     db: &db::DatabasePool,
-    vault: &ActorRef<Vault>,
+    pubkey: &VerifyingKey,
-    pubkey: &authn::PublicKey,
     metadata: &ClientMetadata,
 ) -> Result<i32, Error> {
-    use crate::db::schema::client_metadata;
+    use crate::db::schema::{client_metadata, program_client};
-
-    let pubkey = pubkey.clone();
-    let metadata = metadata.clone();
-
     let mut conn = db.get().await.map_err(|e| {
         error!(error = ?e, "Database pool error");
         Error::DatabasePoolUnavailable
     })?;
 
-    conn.exclusive_transaction(|conn| {
+    let metadata_id = insert_into(client_metadata::table)
-        let vault = vault.clone();
+        .values((
-        let pubkey = pubkey.clone();
+            client_metadata::name.eq(&metadata.name),
-        Box::pin(async move {
+            client_metadata::description.eq(&metadata.description),
-            let metadata_id = insert_into(client_metadata::table)
+            client_metadata::version.eq(&metadata.version),
-                .values((
+        ))
-                    client_metadata::name.eq(&metadata.name),
+        .returning(client_metadata::id)
-                    client_metadata::description.eq(&metadata.description),
+        .get_result::<i32>(&mut conn)
-                    client_metadata::version.eq(&metadata.version),
+        .await
-                ))
+        .map_err(|e| {
-                .returning(client_metadata::id)
+            error!(error = ?e, "Failed to insert client metadata");
-                .get_result::<i32>(conn)
+            Error::DatabaseOperationFailed
-                .await?;
+        })?;
 
-            let client_id = insert_into(program_client::table)
+    let client_id = insert_into(program_client::table)
-                .values((
+        .values((
-                    program_client::public_key.eq(pubkey.to_bytes()),
+            program_client::public_key.eq(pubkey.as_bytes().to_vec()),
-                    program_client::metadata_id.eq(metadata_id),
+            program_client::metadata_id.eq(metadata_id),
-                ))
+            program_client::nonce.eq(1), // pre-incremented; challenge uses 0
-                .on_conflict_do_nothing()
+        ))
-                .returning(program_client::id)
+        .on_conflict_do_nothing()
-                .get_result::<i32>(conn)
+        .returning(program_client::id)
-                .await?;
+        .get_result::<i32>(&mut conn)
+        .await
+        .map_err(|e| {
+            error!(error = ?e, "Failed to insert client metadata");
+            Error::DatabaseOperationFailed
+        })?;
 
-            integrity::sign_entity(
+    Ok(client_id)
-                conn,
-                &vault,
-                &ClientCredentials {
-                    pubkey: pubkey.clone(),
-                },
-                client_id,
-            )
-            .await
-            .map_err(|e| {
-                error!(error = ?e, "Failed to sign integrity tag for new client key");
-                Error::DatabaseOperationFailed
-            })?;
-
-            Ok(client_id)
-        })
-    })
-    .await
 }
 
 async fn sync_client_metadata(
@@ -288,16 +253,14 @@ async fn sync_client_metadata(
 
 async fn challenge_client<T>(
     transport: &mut T,
-    pubkey: authn::PublicKey,
+    pubkey: VerifyingKey,
-    challenge: AuthChallenge,
+    nonce: i32,
 ) -> Result<(), Error>
 where
     T: Bi<Inbound, Result<Outbound, Error>> + ?Sized,
 {
     transport
-        .send(Ok(Outbound::AuthChallenge {
+        .send(Ok(Outbound::AuthChallenge { pubkey, nonce }))
-            challenge: challenge.clone(),
-        }))
         .await
         .map_err(|e| {
             error!(error = ?e, "Failed to send auth challenge");
@@ -314,15 +277,20 @@ where
         Error::Transport
     })?;
 
-    if !pubkey.verify(&challenge, CLIENT_CONTEXT, &signature) {
+    let formatted = format_challenge(nonce, pubkey.as_bytes());
+
+    pubkey.verify_strict(&formatted, &signature).map_err(|_| {
         error!("Challenge solution verification failed");
-        return Err(Error::InvalidChallengeSolution);
+        Error::InvalidChallengeSolution
-    }
+    })?;
 
     Ok(())
 }
 
-pub async fn authenticate<T>(props: &mut ClientConnection, transport: &mut T) -> Result<i32, Error>
+pub async fn authenticate<T>(
+    props: &mut ClientConnection,
+    transport: &mut T,
+) -> Result<VerifyingKey, Error>
 where
     T: Bi<Inbound, Result<Outbound, Error>> + Send + ?Sized,
 {
@@ -330,26 +298,29 @@ where
         return Err(Error::Transport);
     };
 
-    let client_id = if let Some(id) = get_client_id(&props.db, &pubkey).await? {
+    let info = match get_client_and_nonce(&props.db, &pubkey).await? {
-        verify_integrity(&props.db, &props.actors.vault, &pubkey).await?;
+        Some(nonce) => nonce,
-        id
+        None => {
-    } else {
+            approve_new_client(
-        approve_new_client(
+                &props.actors,
-            &props.actors,
+                ClientProfile {
-            ClientProfile {
+                    pubkey,
-                pubkey: pubkey.clone(),
+                    metadata: metadata.clone(),
-                metadata: metadata.clone(),
+                },
-            },
+            )
-        )
+            .await?;
-        .await?;
+            let client_id = insert_client(&props.db, &pubkey, &metadata).await?;
-        insert_client(&props.db, &props.actors.vault, &pubkey, &metadata).await?
+            ClientInfo {
+                id: client_id,
+                current_nonce: 0,
+            }
+        }
     };
 
-    sync_client_metadata(&props.db, client_id, &metadata).await?;
+    sync_client_metadata(&props.db, info.id, &metadata).await?;
-
-    let challenge = AuthChallenge::generate(&mut rand::rng());
-    challenge_client(transport, pubkey, challenge).await?;
 
+    challenge_client(transport, pubkey, info.current_nonce).await?;
+    
     transport
         .send(Ok(Outbound::AuthSuccess))
         .await
@@ -358,5 +329,5 @@ where
             Error::Transport
         })?;
 
-    Ok(client_id)
+    Ok(pubkey)
 }

server/crates/arbiter-server/src/actors/client/mod.rs

@@ -1,35 +1,25 @@
-use crate::{
-    actors::GlobalActors, crypto::integrity::Integrable, db, peers::client::session::ClientSession,
-};
-use arbiter_crypto::authn;
-use arbiter_macros::Hashable;
 use arbiter_proto::{ClientMetadata, transport::Bi};
-
 use kameo::actor::Spawn;
 use tracing::{error, info};
 
+use crate::{
+    actors::{GlobalActors, client::{ session::ClientSession}},
+    db,
+};
+
 #[derive(Debug, Clone)]
 pub struct ClientProfile {
-    pub pubkey: authn::PublicKey,
+    pub pubkey: ed25519_dalek::VerifyingKey,
     pub metadata: ClientMetadata,
 }
 
-#[derive(Hashable)]
-pub struct ClientCredentials {
-    pub pubkey: authn::PublicKey,
-}
-
-impl Integrable for ClientCredentials {
-    const KIND: &'static str = "client_credentials";
-}
-
 pub struct ClientConnection {
     pub(crate) db: db::DatabasePool,
     pub(crate) actors: GlobalActors,
 }
 
 impl ClientConnection {
-    pub const fn new(db: db::DatabasePool, actors: GlobalActors) -> Self {
+    pub fn new(db: db::DatabasePool, actors: GlobalActors) -> Self {
         Self { db, actors }
     }
 }
@@ -41,11 +31,9 @@ pub async fn connect_client<T>(mut props: ClientConnection, transport: &mut T)
 where
     T: Bi<auth::Inbound, Result<auth::Outbound, auth::Error>> + Send + ?Sized,
 {
-    let fut = auth::authenticate(&mut props, transport);
+    match auth::authenticate(&mut props, transport).await {
-    println!("authenticate future size: {}", size_of_val(&fut));
+        Ok(_pubkey) => {
-    match fut.await {
+            ClientSession::spawn(ClientSession::new(props));
-        Ok(client_id) => {
-            ClientSession::spawn(ClientSession::new(props, client_id));
             info!("Client authenticated, session started");
         }
         Err(err) => {

server/crates/arbiter-server/src/actors/client/session.rs

@@ -0,0 +1,72 @@
+use kameo::{Actor, messages};
+use tracing::error;
+
+use crate::{
+    actors::{
+        GlobalActors, client::ClientConnection, flow_coordinator::RegisterClient,
+        keyholder::KeyHolderState,
+    },
+    db,
+};
+
+pub struct ClientSession {
+    props: ClientConnection,
+}
+
+impl ClientSession {
+    pub(crate) fn new(props: ClientConnection) -> Self {
+        Self { props }
+    }
+}
+
+#[messages]
+impl ClientSession {
+    #[message]
+    pub(crate) async fn handle_query_vault_state(&mut self) -> Result<KeyHolderState, Error> {
+        use crate::actors::keyholder::GetState;
+
+        let vault_state = match self.props.actors.key_holder.ask(GetState {}).await {
+            Ok(state) => state,
+            Err(err) => {
+                error!(?err, actor = "client", "keyholder.query.failed");
+                return Err(Error::Internal);
+            }
+        };
+
+        Ok(vault_state)
+    }
+}
+
+impl Actor for ClientSession {
+    type Args = Self;
+
+    type Error = Error;
+
+    async fn on_start(
+        args: Self::Args,
+        this: kameo::prelude::ActorRef<Self>,
+    ) -> Result<Self, Self::Error> {
+        args.props
+            .actors
+            .flow_coordinator
+            .ask(RegisterClient { actor: this })
+            .await
+            .map_err(|_| Error::ConnectionRegistrationFailed)?;
+        Ok(args)
+    }
+}
+
+impl ClientSession {
+    pub fn new_test(db: db::DatabasePool, actors: GlobalActors) -> Self {
+        let props = ClientConnection::new(db, actors);
+        Self { props }
+    }
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("Connection registration failed")]
+    ConnectionRegistrationFailed,
+    #[error("Internal error")]
+    Internal,
+}

server/crates/arbiter-server/src/actors/evm/mod.rs

@@ -1,24 +1,4 @@
-use crate::{
+use alloy::{consensus::TxEip1559, primitives::Address, signers::Signature};
-    actors::vault::{CreateNew, Decrypt, Vault},
-    crypto::integrity,
-    db::{
-        DatabaseError, DatabasePool,
-        models::{self},
-        schema,
-    },
-    evm::{
-        self, ListError, RunKind,
-        policies::{
-            CombinedSettings, Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning,
-            ether_transfer::EtherTransfer, token_transfers::TokenTransfer,
-        },
-    },
-};
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-use alloy::{
-    consensus::TxEip1559, network::TxSignerSync as _, primitives::Address, signers::Signature,
-};
 use diesel::{
     ExpressionMethods, OptionalExtension as _, QueryDsl, SelectableHelper as _, dsl::insert_into,
 };
@@ -26,60 +6,83 @@ use diesel_async::RunQueryDsl;
 use kameo::{Actor, actor::ActorRef, messages};
 use rand::{SeedableRng, rng, rngs::StdRng};
 
+use crate::{
+    actors::keyholder::{CreateNew, Decrypt, KeyHolder},
+    db::{
+        self, DatabaseError, DatabasePool,
+        models::{self, SqliteTimestamp},
+        schema,
+    },
+    evm::{
+        self, RunKind,
+        policies::{
+            FullGrant, Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning,
+            ether_transfer::EtherTransfer, token_transfers::TokenTransfer,
+        },
+    },
+    safe_cell::{SafeCell, SafeCellHandle as _},
+};
+
 pub use crate::evm::safe_signer;
 
-#[derive(Debug, thiserror::Error)]
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
 pub enum SignTransactionError {
     #[error("Wallet not found")]
+    #[diagnostic(code(arbiter::evm::sign::wallet_not_found))]
     WalletNotFound,
 
     #[error("Database error: {0}")]
+    #[diagnostic(code(arbiter::evm::sign::database))]
     Database(#[from] DatabaseError),
 
-    #[error("Vault error: {0}")]
+    #[error("Keyholder error: {0}")]
-    Vault(#[from] crate::actors::vault::Error),
+    #[diagnostic(code(arbiter::evm::sign::keyholder))]
+    Keyholder(#[from] crate::actors::keyholder::Error),
 
-    #[error("Vault mailbox error")]
+    #[error("Keyholder mailbox error")]
-    VaultSend,
+    #[diagnostic(code(arbiter::evm::sign::keyholder_send))]
+    KeyholderSend,
 
     #[error("Signing error: {0}")]
+    #[diagnostic(code(arbiter::evm::sign::signing))]
     Signing(#[from] alloy::signers::Error),
 
     #[error("Policy error: {0}")]
+    #[diagnostic(code(arbiter::evm::sign::vet))]
     Vet(#[from] evm::VetError),
 }
 
-#[derive(Debug, thiserror::Error)]
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
 pub enum Error {
-    #[error("Vault error: {0}")]
+    #[error("Keyholder error: {0}")]
-    Vault(#[from] crate::actors::vault::Error),
+    #[diagnostic(code(arbiter::evm::keyholder))]
+    Keyholder(#[from] crate::actors::keyholder::Error),
 
-    #[error("Vault mailbox error")]
+    #[error("Keyholder mailbox error")]
-    VaultSend,
+    #[diagnostic(code(arbiter::evm::keyholder_send))]
+    KeyholderSend,
 
     #[error("Database error: {0}")]
+    #[diagnostic(code(arbiter::evm::database))]
     Database(#[from] DatabaseError),
-
-    #[error("Integrity violation: {0}")]
-    Integrity(#[from] integrity::Error),
 }
 
 #[derive(Actor)]
 pub struct EvmActor {
-    pub vault: ActorRef<Vault>,
+    pub keyholder: ActorRef<KeyHolder>,
     pub db: DatabasePool,
     pub rng: StdRng,
     pub engine: evm::Engine,
 }
 
 impl EvmActor {
-    pub fn new(vault: ActorRef<Vault>, db: DatabasePool) -> Self {
+    pub fn new(keyholder: ActorRef<KeyHolder>, db: DatabasePool) -> Self {
         // is it safe to seed rng from system once?
         // todo: audit
         let rng = StdRng::from_rng(&mut rng());
-        let engine = evm::Engine::new(db.clone(), vault.clone());
+        let engine = evm::Engine::new(db.clone());
         Self {
-            vault,
+            keyholder,
             db,
             rng,
             engine,
@@ -96,10 +99,10 @@ impl EvmActor {
         let plaintext = key_cell.read_inline(|reader| SafeCell::new(reader.to_vec()));
 
         let aead_id: i32 = self
-            .vault
+            .keyholder
             .ask(CreateNew { plaintext })
             .await
-            .map_err(|_| Error::VaultSend)?;
+            .map_err(|_| Error::KeyholderSend)?;
 
         let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
         let wallet_id = insert_into(schema::evm_wallet::table)
@@ -134,64 +137,50 @@ impl EvmActor {
 #[messages]
 impl EvmActor {
     #[message]
-    pub async fn operator_create_grant(
+    pub async fn useragent_create_grant(
         &mut self,
         basic: SharedGrantSettings,
         grant: SpecificGrant,
-    ) -> Result<i32, Error> {
+    ) -> Result<i32, DatabaseError> {
         match grant {
-            SpecificGrant::EtherTransfer(settings) => self
+            SpecificGrant::EtherTransfer(settings) => {
-                .engine
+                self.engine
-                .create_grant::<EtherTransfer>(CombinedSettings {
+                    .create_grant::<EtherTransfer>(FullGrant {
-                    shared: basic,
+                        basic,
-                    specific: settings,
+                        specific: settings,
-                })
+                    })
-                .await
+                    .await
-                .map_err(Error::from),
+            }
-            SpecificGrant::TokenTransfer(settings) => self
+            SpecificGrant::TokenTransfer(settings) => {
-                .engine
+                self.engine
-                .create_grant::<TokenTransfer>(CombinedSettings {
+                    .create_grant::<TokenTransfer>(FullGrant {
-                    shared: basic,
+                        basic,
-                    specific: settings,
+                        specific: settings,
-                })
+                    })
-                .await
+                    .await
-                .map_err(Error::from),
+            }
         }
     }
 
     #[message]
-    #[expect(clippy::unused_async, reason = "reserved for impl")]
+    pub async fn useragent_delete_grant(&mut self, grant_id: i32) -> Result<(), Error> {
-    pub async fn operator_delete_grant(&mut self, _grant_id: i32) -> Result<(), Error> {
+        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
-        // let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
+        diesel::update(schema::evm_basic_grant::table)
-        // let vault = self.vault.clone();
+            .filter(schema::evm_basic_grant::id.eq(grant_id))
-
+            .set(schema::evm_basic_grant::revoked_at.eq(SqliteTimestamp::now()))
-        // diesel_async::AsyncConnection::transaction(&mut conn, |conn| {
+            .execute(&mut conn)
-        //     Box::pin(async move {
+            .await
-        //         diesel::update(schema::evm_basic_grant::table)
+            .map_err(DatabaseError::from)?;
-        //             .filter(schema::evm_basic_grant::id.eq(grant_id))
+        Ok(())
-        //             .set(schema::evm_basic_grant::revoked_at.eq(SqliteTimestamp::now()))
-        //             .execute(conn)
-        //             .await?;
-
-        //         let signed = integrity::evm::load_signed_grant_by_basic_id(conn, grant_id).await?;
-
-        //         diesel::result::QueryResult::Ok(())
-        //     })
-        // })
-        // .await
-        // .map_err(DatabaseError::from)?;
-
-        // Ok(())
-        todo!()
     }
 
     #[message]
-    pub async fn operator_list_grants(&mut self) -> Result<Vec<Grant<SpecificGrant>>, Error> {
+    pub async fn useragent_list_grants(&mut self) -> Result<Vec<Grant<SpecificGrant>>, Error> {
-        match self.engine.list_all_grants().await {
+        Ok(self
-            Ok(grants) => Ok(grants),
+            .engine
-            Err(ListError::Database(db_err)) => Err(Error::Database(db_err)),
+            .list_all_grants()
-            Err(ListError::Integrity(integrity_err)) => Err(Error::Integrity(integrity_err)),
+            .await
-        }
+            .map_err(DatabaseError::from)?)
     }
 
     #[message]
@@ -257,12 +246,12 @@ impl EvmActor {
         drop(conn);
 
         let raw_key: SafeCell<Vec<u8>> = self
-            .vault
+            .keyholder
             .ask(Decrypt {
                 aead_id: wallet.aead_encrypted_id,
             })
             .await
-            .map_err(|_| SignTransactionError::VaultSend)?;
+            .map_err(|_| SignTransactionError::KeyholderSend)?;
 
         let signer = safe_signer::SafeSigner::from_cell(raw_key)?;
 
@@ -270,6 +259,7 @@ impl EvmActor {
             .evaluate_transaction(wallet_access, transaction.clone(), RunKind::Execution)
             .await?;
 
+        use alloy::network::TxSignerSync as _;
         Ok(signer.sign_transaction_sync(&mut transaction)?)
     }
 }

server/crates/arbiter-server/src/actors/flow_coordinator/client_connect_approval.rs

@@ -1,26 +1,25 @@
-use crate::{
+use std::ops::ControlFlow;
-    actors::flow_coordinator::ApprovalError,
-    peers::{
-        client::ClientProfile,
-        operator::{OperatorSession, session::BeginNewClientApproval},
-    },
-};
 
 use kameo::{
     Actor, messages,
     prelude::{ActorId, ActorRef, ActorStopReason, Context, WeakActorRef},
     reply::ReplySender,
 };
-use std::ops::ControlFlow;
+
+use crate::actors::{
+    client::ClientProfile,
+    flow_coordinator::ApprovalError,
+    user_agent::{UserAgentSession, session::BeginNewClientApproval},
+};
 
 pub struct Args {
     pub client: ClientProfile,
-    pub operators: Vec<ActorRef<OperatorSession>>,
+    pub user_agents: Vec<ActorRef<UserAgentSession>>,
-    pub reply: ReplySender<Result<bool, ApprovalError>>,
+    pub reply: ReplySender<Result<bool, ApprovalError>>
 }
 
 pub struct ClientApprovalController {
-    /// Number of operators that have not yet responded (approval or denial) or died.
+    /// Number of UAs that have not yet responded (approval or denial) or died.
     pending: usize,
     /// Number of approvals received so far.
     approved: usize,
@@ -40,23 +39,18 @@ impl Actor for ClientApprovalController {
     type Error = ();
 
     async fn on_start(
-        Args {
+        Args { client, mut user_agents, reply }: Self::Args,
-            client,
-            operators,
-            reply,
-        }: Self::Args,
         actor_ref: ActorRef<Self>,
     ) -> Result<Self, Self::Error> {
         let this = Self {
-            pending: operators.len(),
+            pending: user_agents.len(),
             approved: 0,
             reply: Some(reply),
         };
 
-        for operator in operators {
+        for user_agent in user_agents.drain(..) {
-            actor_ref.link(&operator).await;
+            actor_ref.link(&user_agent).await;
-
+            let _ = user_agent
-            let _ = operator
                 .tell(BeginNewClientApproval {
                     client: client.clone(),
                     controller: actor_ref.clone(),
@@ -73,10 +67,10 @@ impl Actor for ClientApprovalController {
         _: ActorId,
         _: ActorStopReason,
     ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        // A linked operator died before responding — counts as a non-approval.
+        // A linked UA died before responding — counts as a non-approval.
         self.pending = self.pending.saturating_sub(1);
         if self.pending == 0 {
-            // At least one operator didn't approve: deny.
+            // At least one UA didn't approve: deny.
             self.send_reply(Ok(false));
             return Ok(ControlFlow::Break(ActorStopReason::Normal));
         }
@@ -87,7 +81,7 @@ impl Actor for ClientApprovalController {
 #[messages]
 impl ClientApprovalController {
     #[message(ctx)]
-    pub fn client_approval_answer(&mut self, approved: bool, ctx: &mut Context<Self, ()>) {
+    pub async fn client_approval_answer(&mut self, approved: bool, ctx: &mut Context<Self, ()>) {
         if !approved {
             // Denial wins immediately regardless of other pending responses.
             self.send_reply(Ok(false));
@@ -99,7 +93,7 @@ impl ClientApprovalController {
         self.pending = self.pending.saturating_sub(1);
 
         if self.pending == 0 {
-            // Every connected operator approved.
+            // Every connected UA approved.
             self.send_reply(Ok(true));
             ctx.stop();
         }

server/crates/arbiter-server/src/actors/flow_coordinator/mod.rs

@@ -1,10 +1,4 @@
-use crate::{
+use std::{collections::HashMap, ops::ControlFlow};
-    actors::{
-        flow_coordinator::client_connect_approval::ClientApprovalController,
-        operator_registry::{GetConnected, OperatorRegistry},
-    },
-    peers::client::{ClientProfile, session::ClientSession},
-};
 
 use kameo::{
     Actor,
@@ -13,23 +7,20 @@ use kameo::{
     prelude::{ActorStopReason, Context, WeakActorRef},
     reply::DelegatedReply,
 };
-use std::{collections::HashMap, ops::ControlFlow};
 use tracing::info;
 
+use crate::actors::{
+    client::{ClientProfile, session::ClientSession},
+    flow_coordinator::client_connect_approval::ClientApprovalController,
+    user_agent::session::UserAgentSession,
+};
+
 pub mod client_connect_approval;
 
+#[derive(Default)]
 pub struct FlowCoordinator {
+    pub user_agents: HashMap<ActorId, ActorRef<UserAgentSession>>,
     pub clients: HashMap<ActorId, ActorRef<ClientSession>>,
-    operator_registry: ActorRef<OperatorRegistry>,
-}
-
-impl FlowCoordinator {
-    pub fn new(operator_registry: ActorRef<OperatorRegistry>) -> Self {
-        Self {
-            clients: HashMap::default(),
-            operator_registry,
-        }
-    }
 }
 
 impl Actor for FlowCoordinator {
@@ -47,7 +38,13 @@ impl Actor for FlowCoordinator {
         id: ActorId,
         _: ActorStopReason,
     ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        if self.clients.remove(&id).is_some() {
+        if self.user_agents.remove(&id).is_some() {
+            info!(
+                ?id,
+                actor = "FlowCoordinator",
+                event = "useragent.disconnected"
+            );
+        } else if self.clients.remove(&id).is_some() {
             info!(
                 ?id,
                 actor = "FlowCoordinator",
@@ -66,12 +63,23 @@ impl Actor for FlowCoordinator {
 
 #[derive(Debug, thiserror::Error, Clone, PartialEq, Eq, Hash)]
 pub enum ApprovalError {
-    #[error("No operators connected")]
+    #[error("No user agents connected")]
-    NoOperatorsConnected,
+    NoUserAgentsConnected,
 }
 
 #[messages]
 impl FlowCoordinator {
+    #[message(ctx)]
+    pub async fn register_user_agent(
+        &mut self,
+        actor: ActorRef<UserAgentSession>,
+        ctx: &mut Context<Self, ()>,
+    ) {
+        info!(id = %actor.id(), actor = "FlowCoordinator", event = "useragent.connected");
+        ctx.actor_ref().link(&actor).await;
+        self.user_agents.insert(actor.id(), actor);
+    }
+
     #[message(ctx)]
     pub async fn register_client(
         &mut self,
@@ -93,19 +101,15 @@ impl FlowCoordinator {
             unreachable!("Expected `request_client_approval` to have callback channel");
         };
 
-        let Ok(refs) = self.operator_registry.ask(GetConnected).await else {
+        let refs: Vec<_> = self.user_agents.values().cloned().collect();
-            reply_sender.send(Err(ApprovalError::NoOperatorsConnected));
-            return reply;
-        };
-
         if refs.is_empty() {
-            reply_sender.send(Err(ApprovalError::NoOperatorsConnected));
+            reply_sender.send(Err(ApprovalError::NoUserAgentsConnected));
             return reply;
         }
 
         ClientApprovalController::spawn(client_connect_approval::Args {
             client,
-            operators: refs,
+            user_agents: refs,
             reply: reply_sender,
         });
 

server/crates/arbiter-server/src/actors/keyholder/encryption.rs

@@ -0,0 +1 @@
+pub mod v1;

server/crates/arbiter-server/src/actors/keyholder/encryption/v1.rs

@@ -0,0 +1,243 @@
+use std::ops::Deref as _;
+
+use argon2::{Algorithm, Argon2, password_hash::Salt as ArgonSalt};
+use chacha20poly1305::{
+    AeadInPlace, Key, KeyInit as _, XChaCha20Poly1305, XNonce,
+    aead::{AeadMut, Error, Payload},
+};
+use rand::{
+    Rng as _, SeedableRng,
+    rngs::{StdRng, SysRng},
+};
+
+use crate::safe_cell::{SafeCell, SafeCellHandle as _};
+
+pub const ROOT_KEY_TAG: &[u8] = "arbiter/seal/v1".as_bytes();
+pub const TAG: &[u8] = "arbiter/private-key/v1".as_bytes();
+
+pub const NONCE_LENGTH: usize = 24;
+
+#[derive(Default)]
+pub struct Nonce([u8; NONCE_LENGTH]);
+impl Nonce {
+    pub fn increment(&mut self) {
+        for i in (0..self.0.len()).rev() {
+            if self.0[i] == 0xFF {
+                self.0[i] = 0;
+            } else {
+                self.0[i] += 1;
+                break;
+            }
+        }
+    }
+
+    pub fn to_vec(&self) -> Vec<u8> {
+        self.0.to_vec()
+    }
+}
+impl<'a> TryFrom<&'a [u8]> for Nonce {
+    type Error = ();
+
+    fn try_from(value: &'a [u8]) -> Result<Self, Self::Error> {
+        if value.len() != NONCE_LENGTH {
+            return Err(());
+        }
+        let mut nonce = [0u8; NONCE_LENGTH];
+        nonce.copy_from_slice(value);
+        Ok(Self(nonce))
+    }
+}
+
+pub struct KeyCell(pub SafeCell<Key>);
+impl From<SafeCell<Key>> for KeyCell {
+    fn from(value: SafeCell<Key>) -> Self {
+        Self(value)
+    }
+}
+impl TryFrom<SafeCell<Vec<u8>>> for KeyCell {
+    type Error = ();
+
+    fn try_from(mut value: SafeCell<Vec<u8>>) -> Result<Self, Self::Error> {
+        let value = value.read();
+        if value.len() != size_of::<Key>() {
+            return Err(());
+        }
+        let cell = SafeCell::new_inline(|cell_write: &mut Key| {
+            cell_write.copy_from_slice(&value);
+        });
+        Ok(Self(cell))
+    }
+}
+
+impl KeyCell {
+    pub fn new_secure_random() -> Self {
+        let key = SafeCell::new_inline(|key_buffer: &mut Key| {
+            #[allow(
+                clippy::unwrap_used,
+                reason = "Rng failure is unrecoverable and should panic"
+            )]
+            let mut rng = StdRng::try_from_rng(&mut SysRng).unwrap();
+            rng.fill_bytes(key_buffer);
+        });
+
+        key.into()
+    }
+
+    pub fn encrypt_in_place(
+        &mut self,
+        nonce: &Nonce,
+        associated_data: &[u8],
+        mut buffer: impl AsMut<Vec<u8>>,
+    ) -> Result<(), Error> {
+        let key_reader = self.0.read();
+        let key_ref = key_reader.deref();
+        let cipher = XChaCha20Poly1305::new(key_ref);
+        let nonce = XNonce::from_slice(nonce.0.as_ref());
+        let buffer = buffer.as_mut();
+        cipher.encrypt_in_place(nonce, associated_data, buffer)
+    }
+    pub fn decrypt_in_place(
+        &mut self,
+        nonce: &Nonce,
+        associated_data: &[u8],
+        buffer: &mut SafeCell<Vec<u8>>,
+    ) -> Result<(), Error> {
+        let key_reader = self.0.read();
+        let key_ref = key_reader.deref();
+        let cipher = XChaCha20Poly1305::new(key_ref);
+        let nonce = XNonce::from_slice(nonce.0.as_ref());
+        let mut buffer = buffer.write();
+        let buffer: &mut Vec<u8> = buffer.as_mut();
+        cipher.decrypt_in_place(nonce, associated_data, buffer)
+    }
+
+    pub fn encrypt(
+        &mut self,
+        nonce: &Nonce,
+        associated_data: &[u8],
+        plaintext: impl AsRef<[u8]>,
+    ) -> Result<Vec<u8>, Error> {
+        let key_reader = self.0.read();
+        let key_ref = key_reader.deref();
+        let mut cipher = XChaCha20Poly1305::new(key_ref);
+        let nonce = XNonce::from_slice(nonce.0.as_ref());
+
+        let ciphertext = cipher.encrypt(
+            nonce,
+            Payload {
+                msg: plaintext.as_ref(),
+                aad: associated_data,
+            },
+        )?;
+        Ok(ciphertext)
+    }
+}
+
+pub type Salt = [u8; ArgonSalt::RECOMMENDED_LENGTH];
+
+pub fn generate_salt() -> Salt {
+    let mut salt = Salt::default();
+    #[allow(
+        clippy::unwrap_used,
+        reason = "Rng failure is unrecoverable and should panic"
+    )]
+    let mut rng = StdRng::try_from_rng(&mut SysRng).unwrap();
+    rng.fill_bytes(&mut salt);
+    salt
+}
+
+/// User password might be of different length, have not enough entropy, etc...
+/// Derive a fixed-length key from the password using Argon2id, which is designed for password hashing and key derivation.
+pub fn derive_seal_key(mut password: SafeCell<Vec<u8>>, salt: &Salt) -> KeyCell {
+    #[allow(clippy::unwrap_used)]
+    let params = argon2::Params::new(262_144, 3, 4, None).unwrap();
+    let hasher = Argon2::new(Algorithm::Argon2id, argon2::Version::V0x13, params);
+    let mut key = SafeCell::new(Key::default());
+    password.read_inline(|password_source| {
+        let mut key_buffer = key.write();
+        let key_buffer: &mut [u8] = key_buffer.as_mut();
+
+        #[allow(
+            clippy::unwrap_used,
+            reason = "Better fail completely than return a weak key"
+        )]
+        hasher
+            .hash_password_into(password_source.deref(), salt, key_buffer)
+            .unwrap();
+    });
+
+    key.into()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::safe_cell::SafeCell;
+
+    #[test]
+    pub fn derive_seal_key_deterministic() {
+        static PASSWORD: &[u8] = b"password";
+        let password = SafeCell::new(PASSWORD.to_vec());
+        let password2 = SafeCell::new(PASSWORD.to_vec());
+        let salt = generate_salt();
+
+        let mut key1 = derive_seal_key(password, &salt);
+        let mut key2 = derive_seal_key(password2, &salt);
+
+        let key1_reader = key1.0.read();
+        let key2_reader = key2.0.read();
+
+        assert_eq!(key1_reader.deref(), key2_reader.deref());
+    }
+
+    #[test]
+    pub fn successful_derive() {
+        static PASSWORD: &[u8] = b"password";
+        let password = SafeCell::new(PASSWORD.to_vec());
+        let salt = generate_salt();
+
+        let mut key = derive_seal_key(password, &salt);
+        let key_reader = key.0.read();
+        let key_ref = key_reader.deref();
+
+        assert_ne!(key_ref.as_slice(), &[0u8; 32][..]);
+    }
+
+    #[test]
+    pub fn encrypt_decrypt() {
+        static PASSWORD: &[u8] = b"password";
+        let password = SafeCell::new(PASSWORD.to_vec());
+        let salt = generate_salt();
+
+        let mut key = derive_seal_key(password, &salt);
+        let nonce = Nonce(*b"unique nonce 123 1231233"); // 24 bytes for XChaCha20Poly1305
+        let associated_data = b"associated data";
+        let mut buffer = b"secret data".to_vec();
+
+        key.encrypt_in_place(&nonce, associated_data, &mut buffer)
+            .unwrap();
+        assert_ne!(buffer, b"secret data");
+
+        let mut buffer = SafeCell::new(buffer);
+
+        key.decrypt_in_place(&nonce, associated_data, &mut buffer)
+            .unwrap();
+
+        let buffer = buffer.read();
+        assert_eq!(*buffer, b"secret data");
+    }
+
+    #[test]
+    // We should fuzz this
+    pub fn test_nonce_increment() {
+        let mut nonce = Nonce([0u8; NONCE_LENGTH]);
+        nonce.increment();
+
+        assert_eq!(
+            nonce.0,
+            [
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
+            ]
+        );
+    }
+}

server/crates/arbiter-server/src/actors/keyholder/mod.rs

@@ -1,98 +1,85 @@
-use crate::{
-    crypto::{
-        KeyCell, derive_key,
-        encryption::v1::{self, Nonce},
-        integrity::v1::HmacSha256,
-    },
-    db::{
-        self,
-        models::{self, RootKeyHistory},
-        schema::{self},
-    },
-};
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
 use chrono::Utc;
 use diesel::{
     ExpressionMethods as _, OptionalExtension, QueryDsl, SelectableHelper,
     dsl::{insert_into, update},
 };
 use diesel_async::{AsyncConnection, RunQueryDsl};
-use hmac::{KeyInit as _, Mac as _};
+use kameo::{Actor, Reply, messages};
-use kameo::{Actor, Reply, actor::ActorRef, messages};
-use kameo_actors::message_bus::{MessageBus, Publish};
 use strum::{EnumDiscriminants, IntoDiscriminant};
 use tracing::{error, info};
 
-pub mod events {
+use crate::safe_cell::SafeCell;
+use crate::{
+    db::{
+        self,
+        models::{self, RootKeyHistory},
+        schema::{self},
+    },
+    safe_cell::SafeCellHandle as _,
+};
+use encryption::v1::{self, KeyCell, Nonce};
 
-    #[derive(Clone, Copy)]
+pub mod encryption;
-    pub struct Bootstrapped;
-
-    #[derive(Clone, Copy)]
-    pub struct Unsealed;
-
-    #[derive(Clone, Copy)]
-    pub struct VaultResealed;
-}
-
-#[derive(Debug, thiserror::Error)]
-pub enum Error {
-    #[error("Vault is already bootstrapped")]
-    AlreadyBootstrapped,
-    #[error("Vault is not bootstrapped")]
-    NotBootstrapped,
-    #[error("Vault is sealed")]
-    Sealed,
-    #[error("Invalid key provided")]
-    InvalidKey,
-
-    #[error("Requested aead entry not found")]
-    NotFound,
-
-    #[error("Encryption error: {0}")]
-    Encryption(#[from] chacha20poly1305::aead::Error),
-
-    #[error("Database error: {0}")]
-    DatabaseConnection(#[from] db::PoolError),
-
-    #[error("Database transaction error: {0}")]
-    DatabaseTransaction(#[from] diesel::result::Error),
-
-    #[error("Broken database")]
-    BrokenDatabase,
-}
-
-struct Unsealed {
-    root_key_history_id: i32,
-    root_key: KeyCell,
-}
 
 #[derive(Default, EnumDiscriminants)]
-#[strum_discriminants(derive(Reply), vis(pub), name(VaultState))]
+#[strum_discriminants(derive(Reply), vis(pub), name(KeyHolderState))]
 enum State {
     #[default]
     Unbootstrapped,
     Sealed {
         root_key_history_id: i32,
     },
-    Unsealed(Unsealed),
+    Unsealed {
+        root_key_history_id: i32,
+        root_key: KeyCell,
+    },
+}
+
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
+pub enum Error {
+    #[error("Keyholder is already bootstrapped")]
+    #[diagnostic(code(arbiter::keyholder::already_bootstrapped))]
+    AlreadyBootstrapped,
+    #[error("Keyholder is not bootstrapped")]
+    #[diagnostic(code(arbiter::keyholder::not_bootstrapped))]
+    NotBootstrapped,
+    #[error("Invalid key provided")]
+    #[diagnostic(code(arbiter::keyholder::invalid_key))]
+    InvalidKey,
+
+    #[error("Requested aead entry not found")]
+    #[diagnostic(code(arbiter::keyholder::aead_not_found))]
+    NotFound,
+
+    #[error("Encryption error: {0}")]
+    #[diagnostic(code(arbiter::keyholder::encryption_error))]
+    Encryption(#[from] chacha20poly1305::aead::Error),
+
+    #[error("Database error: {0}")]
+    #[diagnostic(code(arbiter::keyholder::database_error))]
+    DatabaseConnection(#[from] db::PoolError),
+
+    #[error("Database transaction error: {0}")]
+    #[diagnostic(code(arbiter::keyholder::database_transaction_error))]
+    DatabaseTransaction(#[from] diesel::result::Error),
+
+    #[error("Broken database")]
+    #[diagnostic(code(arbiter::keyholder::broken_database))]
+    BrokenDatabase,
 }
 
 /// Manages vault root key and tracks current state of the vault (bootstrapped/unbootstrapped, sealed/unsealed).
-///
 /// Provides API for encrypting and decrypting data using the vault root key.
 /// Abstraction over database to make sure nonces are never reused and encryption keys are never exposed in plaintext outside of this actor.
 #[derive(Actor)]
-pub struct Vault {
+pub struct KeyHolder {
     db: db::DatabasePool,
     state: State,
-    events: ActorRef<MessageBus>,
 }
 
 #[messages]
-impl Vault {
+impl KeyHolder {
-    pub async fn new(db: db::DatabasePool, events: ActorRef<MessageBus>) -> Result<Self, Error> {
+    pub async fn new(db: db::DatabasePool) -> Result<Self, Error> {
         let state = {
             let mut conn = db.get().await?;
 
@@ -110,10 +97,10 @@ impl Vault {
             }
         };
 
-        Ok(Self { db, state, events })
+        Ok(Self { db, state })
     }
 
-    // Exclusive transaction to avoid race condtions if multiple vaults write
+    // Exclusive transaction to avoid race condtions if multiple keyholders write
     // additional layer of protection against nonce-reuse
     async fn get_new_nonce(pool: &db::DatabasePool, root_key_id: i32) -> Result<Nonce, Error> {
         let mut conn = pool.get().await?;
@@ -127,13 +114,14 @@ impl Vault {
                         .first(conn)
                         .await?;
 
-                    let mut nonce = Nonce::try_from(current_nonce.as_slice()).map_err(|()| {
+                    let mut nonce =
-                        error!(
+                        v1::Nonce::try_from(current_nonce.as_slice()).map_err(|_| {
-                            "Broken database: invalid nonce for root key history id={}",
+                            error!(
-                            root_key_id
+                                "Broken database: invalid nonce for root key history id={}",
-                        );
+                                root_key_id
-                        Error::BrokenDatabase
+                            );
-                    })?;
+                            Error::BrokenDatabase
+                        })?;
                     nonce.increment();
 
                     update(schema::root_key_history::table)
@@ -150,26 +138,18 @@ impl Vault {
         Ok(nonce)
     }
 
-    const fn expect_unsealed(state: &mut State) -> Result<&mut Unsealed, Error> {
-        match state {
-            State::Unsealed(unsealed) => Ok(unsealed),
-            State::Unbootstrapped => Err(Error::NotBootstrapped),
-            State::Sealed { .. } => Err(Error::Sealed),
-        }
-    }
-
     #[message]
     pub async fn bootstrap(&mut self, seal_key_raw: SafeCell<Vec<u8>>) -> Result<(), Error> {
         if !matches!(self.state, State::Unbootstrapped) {
             return Err(Error::AlreadyBootstrapped);
         }
         let salt = v1::generate_salt();
-        let mut seal_key = derive_key(seal_key_raw, &salt);
+        let mut seal_key = v1::derive_seal_key(seal_key_raw, &salt);
         let mut root_key = KeyCell::new_secure_random();
 
         // Zero nonces are fine because they are one-time
-        let root_key_nonce = Nonce::default();
+        let root_key_nonce = v1::Nonce::default();
-        let data_encryption_nonce = Nonce::default();
+        let data_encryption_nonce = v1::Nonce::default();
 
         let root_key_ciphertext: Vec<u8> = root_key.0.read_inline(|reader| {
             let root_key_reader = reader.as_slice();
@@ -210,13 +190,12 @@ impl Vault {
             })
             .await?;
 
-        self.state = State::Unsealed(Unsealed {
+        self.state = State::Unsealed {
             root_key,
             root_key_history_id,
-        });
+        };
 
-        info!("Vault bootstrapped successfully");
+        info!("Keyholder bootstrapped successfully");
-        let _ = self.events.tell(Publish(events::Bootstrapped)).await;
 
         Ok(())
     }
@@ -235,6 +214,7 @@ impl Vault {
             let mut conn = self.db.get().await?;
             schema::root_key_history::table
                 .filter(schema::root_key_history::id.eq(*root_key_history_id))
+                .select(schema::root_key_history::data_encryption_nonce)
                 .select(RootKeyHistory::as_select())
                 .first(&mut conn)
                 .await?
@@ -245,15 +225,16 @@ impl Vault {
             error!("Broken database: invalid salt for root key");
             Error::BrokenDatabase
         })?;
-        let mut seal_key = derive_key(seal_key_raw, &salt);
+        let mut seal_key = v1::derive_seal_key(seal_key_raw, &salt);
 
         let mut root_key = SafeCell::new(current_key.ciphertext.clone());
 
-        let nonce =
+        let nonce = v1::Nonce::try_from(current_key.root_key_encryption_nonce.as_slice()).map_err(
-            Nonce::try_from(current_key.root_key_encryption_nonce.as_slice()).map_err(|()| {
+            |_| {
                 error!("Broken database: invalid nonce for root key");
                 Error::BrokenDatabase
-            })?;
+            },
+        )?;
 
         seal_key
             .decrypt_in_place(&nonce, v1::ROOT_KEY_TAG, &mut root_key)
@@ -262,23 +243,25 @@ impl Vault {
                 Error::InvalidKey
             })?;
 
-        self.state = State::Unsealed(Unsealed {
+        self.state = State::Unsealed {
             root_key_history_id: current_key.id,
-            root_key: KeyCell::try_from(root_key).map_err(|err| {
+            root_key: v1::KeyCell::try_from(root_key).map_err(|err| {
                 error!(?err, "Broken database: invalid encryption key size");
                 Error::BrokenDatabase
             })?,
-        });
+        };
 
-        info!("Vault unsealed successfully");
+        info!("Keyholder unsealed successfully");
-        let _ = self.events.tell(Publish(events::Unsealed)).await;
 
         Ok(())
     }
 
+    // Decrypts the `aead_encrypted` entry with the given ID and returns the plaintext
     #[message]
     pub async fn decrypt(&mut self, aead_id: i32) -> Result<SafeCell<Vec<u8>>, Error> {
-        let Unsealed { root_key, .. } = Self::expect_unsealed(&mut self.state)?;
+        let State::Unsealed { root_key, .. } = &mut self.state else {
+            return Err(Error::NotBootstrapped);
+        };
 
         let row: models::AeadEncrypted = {
             let mut conn = self.db.get().await?;
@@ -291,7 +274,7 @@ impl Vault {
                 .ok_or(Error::NotFound)?
         };
 
-        let nonce = Nonce::try_from(row.current_nonce.as_slice()).map_err(|()| {
+        let nonce = v1::Nonce::try_from(row.current_nonce.as_slice()).map_err(|_| {
             error!(
                 "Broken database: invalid nonce for aead_encrypted id={}",
                 aead_id
@@ -306,10 +289,13 @@ impl Vault {
     // Creates new `aead_encrypted` entry in the database and returns it's ID
     #[message]
     pub async fn create_new(&mut self, mut plaintext: SafeCell<Vec<u8>>) -> Result<i32, Error> {
-        let Unsealed {
+        let State::Unsealed {
             root_key,
             root_key_history_id,
-        } = Self::expect_unsealed(&mut self.state)?;
+        } = &mut self.state
+        else {
+            return Err(Error::NotBootstrapped);
+        };
 
         // Order matters here - `get_new_nonce` acquires connection, so we need to call it before next acquire
         // Borrow checker note: &mut borrow a few lines above is disjoint from this field
@@ -339,84 +325,41 @@ impl Vault {
     }
 
     #[message]
-    pub fn get_state(&self) -> VaultState {
+    pub fn get_state(&self) -> KeyHolderState {
         self.state.discriminant()
     }
 
     #[message]
-    pub fn sign_integrity(&mut self, mac_input: Vec<u8>) -> Result<(i32, Vec<u8>), Error> {
+    pub fn seal(&mut self) -> Result<(), Error> {
-        let Unsealed {
+        let State::Unsealed {
-            root_key,
-            root_key_history_id,
-        } = Self::expect_unsealed(&mut self.state)?;
-
-        let mut hmac = root_key
-            .0
-            .read_inline(|k| match HmacSha256::new_from_slice(k) {
-                Ok(v) => v,
-                Err(_) => unreachable!("HMAC accepts keys of any size"),
-            });
-        hmac.update(&root_key_history_id.to_be_bytes());
-        hmac.update(&mac_input);
-
-        let mac = hmac.finalize().into_bytes().to_vec();
-        Ok((*root_key_history_id, mac))
-    }
-
-    #[message]
-    pub fn verify_integrity(
-        &mut self,
-        mac_input: Vec<u8>,
-        expected_mac: Vec<u8>,
-        key_version: i32,
-    ) -> Result<bool, Error> {
-        let Unsealed {
-            root_key,
-            root_key_history_id,
-        } = Self::expect_unsealed(&mut self.state)?;
-
-        if *root_key_history_id != key_version {
-            return Ok(false);
-        }
-
-        let mut hmac = root_key
-            .0
-            .read_inline(|k| match HmacSha256::new_from_slice(k) {
-                Ok(v) => v,
-                Err(_) => unreachable!("HMAC accepts keys of any size"),
-            });
-        hmac.update(&key_version.to_be_bytes());
-        hmac.update(&mac_input);
-
-        Ok(hmac.verify_slice(&expected_mac).is_ok())
-    }
-
-    #[message]
-    pub async fn seal(&mut self) -> Result<(), Error> {
-        let Unsealed {
             root_key_history_id,
             ..
-        } = Self::expect_unsealed(&mut self.state)?;
+        } = &self.state
-
+        else {
+            return Err(Error::NotBootstrapped);
+        };
         self.state = State::Sealed {
             root_key_history_id: *root_key_history_id,
         };
-        let _ = self.events.tell(Publish(events::VaultResealed)).await;
         Ok(())
     }
 }
 
 #[cfg(test)]
 mod tests {
-    use crate::actors::GlobalActors;
+    use diesel::SelectableHelper;
-    use arbiter_crypto::safecell::SafeCellHandle as _;
+
+    use diesel_async::RunQueryDsl;
+
+    use crate::{
+        db::{self},
+        safe_cell::SafeCell,
+    };
 
     use super::*;
 
-    async fn bootstrapped_actor(db: &db::DatabasePool) -> Vault {
+    async fn bootstrapped_actor(db: &db::DatabasePool) -> KeyHolder {
-        let mut actor = Vault::new(db.clone(), GlobalActors::spawn_message_bus())
+        let mut actor = KeyHolder::new(db.clone()).await.unwrap();
-            .await
-            .unwrap();
         let seal_key = SafeCell::new(b"test-seal-key".to_vec());
         actor.bootstrap(seal_key).await.unwrap();
         actor
@@ -428,17 +371,17 @@ mod tests {
         let db = db::create_test_pool().await;
         let mut actor = bootstrapped_actor(&db).await;
         let root_key_history_id = match actor.state {
-            State::Unsealed(Unsealed {
+            State::Unsealed {
                 root_key_history_id,
                 ..
-            }) => root_key_history_id,
+            } => root_key_history_id,
             _ => panic!("expected unsealed state"),
         };
 
-        let n1 = Vault::get_new_nonce(&db, root_key_history_id)
+        let n1 = KeyHolder::get_new_nonce(&db, root_key_history_id)
             .await
             .unwrap();
-        let n2 = Vault::get_new_nonce(&db, root_key_history_id)
+        let n2 = KeyHolder::get_new_nonce(&db, root_key_history_id)
             .await
             .unwrap();
         assert!(n2.to_vec() > n1.to_vec(), "nonce must increase");

server/crates/arbiter-server/src/actors/mod.rs

@@ -1,59 +1,50 @@
+use kameo::actor::{ActorRef, Spawn};
+use miette::Diagnostic;
+use thiserror::Error;
+
 use crate::{
     actors::{
         bootstrap::Bootstrapper, evm::EvmActor, flow_coordinator::FlowCoordinator,
-        operator_registry::OperatorRegistry, vault::Vault,
+        keyholder::KeyHolder,
     },
     db,
 };
 
-use kameo::actor::{ActorRef, Spawn};
-use kameo_actors::{DeliveryStrategy, message_bus::MessageBus};
-use thiserror::Error;
-
 pub mod bootstrap;
-pub mod evm;
+pub mod client;
+mod evm;
 pub mod flow_coordinator;
-pub mod operator_registry;
+pub mod keyholder;
-pub mod vault;
+pub mod user_agent;
 
-#[derive(Error, Debug)]
+#[derive(Error, Debug, Diagnostic)]
 pub enum SpawnError {
     #[error("Failed to spawn Bootstrapper actor")]
+    #[diagnostic(code(SpawnError::Bootstrapper))]
     Bootstrapper(#[from] bootstrap::Error),
 
-    #[error("Failed to spawn Vault actor")]
+    #[error("Failed to spawn KeyHolder actor")]
-    Vault(#[from] vault::Error),
+    #[diagnostic(code(SpawnError::KeyHolder))]
+    KeyHolder(#[from] keyholder::Error),
 }
 
 /// Long-lived actors that are shared across all connections and handle global state and operations
 #[derive(Clone)]
 pub struct GlobalActors {
-    pub vault: ActorRef<Vault>,
+    pub key_holder: ActorRef<KeyHolder>,
     pub bootstrapper: ActorRef<Bootstrapper>,
     pub flow_coordinator: ActorRef<FlowCoordinator>,
-    pub operator_registry: ActorRef<OperatorRegistry>,
     pub evm: ActorRef<EvmActor>,
-    pub events: ActorRef<MessageBus>,
 }
 
 impl GlobalActors {
-    pub fn spawn_message_bus() -> ActorRef<MessageBus> {
-        MessageBus::spawn(MessageBus::new(DeliveryStrategy::Guaranteed))
-    }
-
     pub async fn spawn(db: db::DatabasePool) -> Result<Self, SpawnError> {
-        let message_bus = Self::spawn_message_bus();
+        let key_holder = KeyHolder::spawn(KeyHolder::new(db.clone()).await?);
-        let key_holder = Vault::spawn(Vault::new(db.clone(), message_bus.clone()).await?);
-        let operator_registry = OperatorRegistry::spawn(OperatorRegistry::default());
         Ok(Self {
             bootstrapper: Bootstrapper::spawn(Bootstrapper::new(&db).await?),
             evm: EvmActor::spawn(EvmActor::new(key_holder.clone(), db)),
-            vault: key_holder,
+            key_holder,
-            flow_coordinator: FlowCoordinator::spawn(FlowCoordinator::new(
+            flow_coordinator: FlowCoordinator::spawn(FlowCoordinator::default()),
-                operator_registry.clone(),
-            )),
-            operator_registry,
-            events: message_bus,
         })
     }
 }

server/crates/arbiter-server/src/actors/operator_registry.rs

@@ -1,61 +0,0 @@
-use crate::peers::operator::OperatorSession;
-
-use kameo::{
-    Actor,
-    actor::{ActorId, ActorRef},
-    error::Infallible,
-    messages,
-    prelude::{ActorStopReason, Context, WeakActorRef},
-};
-use std::{collections::HashMap, ops::ControlFlow};
-use tracing::info;
-
-#[derive(Default)]
-pub struct OperatorRegistry {
-    connected: HashMap<ActorId, ActorRef<OperatorSession>>,
-}
-
-impl Actor for OperatorRegistry {
-    type Args = Self;
-
-    type Error = Infallible;
-
-    async fn on_start(args: Self::Args, _: ActorRef<Self>) -> Result<Self, Self::Error> {
-        Ok(args)
-    }
-
-    async fn on_link_died(
-        &mut self,
-        _: WeakActorRef<Self>,
-        id: ActorId,
-        _: ActorStopReason,
-    ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        if self.connected.remove(&id).is_some() {
-            info!(
-                ?id,
-                actor = "OperatorRegistry",
-                event = "operator.disconnected"
-            );
-        }
-        Ok(ControlFlow::Continue(()))
-    }
-}
-
-#[messages]
-impl OperatorRegistry {
-    #[message(ctx)]
-    pub async fn connect_operator(
-        &mut self,
-        actor: ActorRef<OperatorSession>,
-        ctx: &mut Context<Self, ()>,
-    ) {
-        info!(id = %actor.id(), actor = "OperatorRegistry", event = "operator.connected");
-        ctx.actor_ref().link(&actor).await;
-        self.connected.insert(actor.id(), actor);
-    }
-
-    #[message]
-    pub fn get_connected(&self) -> Vec<ActorRef<OperatorSession>> {
-        self.connected.values().cloned().collect()
-    }
-}

server/crates/arbiter-server/src/actors/user_agent/auth.rs

@@ -1,19 +1,18 @@
-use super::{Credentials, OperatorConnection};
-use arbiter_crypto::authn::{self, AuthChallenge};
 use arbiter_proto::transport::Bi;
-
-use state::{
-    AuthContext, AuthError, AuthEvents, AuthStateMachine, AuthStates, ChallengeRequest,
-    ChallengeSolution,
-};
 use tracing::error;
 
+use crate::actors::user_agent::{
+    AuthPublicKey, UserAgentConnection,
+    auth::state::{AuthContext, AuthStateMachine},
+};
+
 mod state;
+use state::*;
 
 #[derive(Debug, Clone)]
 pub enum Inbound {
     AuthChallengeRequest {
-        pubkey: authn::PublicKey,
+        pubkey: AuthPublicKey,
         bootstrap_token: Option<String>,
     },
     AuthChallengeSolution {
@@ -38,16 +37,9 @@ impl Error {
     }
 }
 
-impl From<diesel::result::Error> for Error {
-    fn from(e: diesel::result::Error) -> Self {
-        error!(?e, "Database error");
-        Self::internal("Database error")
-    }
-}
-
 #[derive(Debug, Clone)]
 pub enum Outbound {
-    AuthChallenge { challenge: AuthChallenge },
+    AuthChallenge { nonce: i32 },
     AuthSuccess,
 }
 
@@ -55,11 +47,12 @@ fn parse_auth_event(payload: Inbound) -> AuthEvents {
     match payload {
         Inbound::AuthChallengeRequest {
             pubkey,
-            bootstrap_token,
+            bootstrap_token: None,
-        } => AuthEvents::AuthRequest(ChallengeRequest {
+        } => AuthEvents::AuthRequest(ChallengeRequest { pubkey }),
+        Inbound::AuthChallengeRequest {
             pubkey,
-            bootstrap_token,
+            bootstrap_token: Some(token),
-        }),
+        } => AuthEvents::BootstrapAuthRequest(BootstrapAuthRequest { pubkey, token }),
         Inbound::AuthChallengeSolution { signature } => {
             AuthEvents::ReceivedSolution(ChallengeSolution {
                 solution: signature,
@@ -69,21 +62,22 @@ fn parse_auth_event(payload: Inbound) -> AuthEvents {
 }
 
 pub async fn authenticate<T>(
-    props: &mut OperatorConnection,
+    props: &mut UserAgentConnection,
-    transport: &mut T,
+    transport: T,
-) -> Result<Credentials, Error>
+) -> Result<AuthPublicKey, Error>
 where
-    T: Bi<Inbound, Result<Outbound, Error>> + Send + ?Sized,
+    T: Bi<Inbound, Result<Outbound, Error>> + Send,
 {
     let mut state = AuthStateMachine::new(AuthContext::new(props, transport));
 
     loop {
+        // `state` holds a mutable reference to `props` so we can't access it directly here
         let Some(payload) = state.context_mut().transport.recv().await else {
             return Err(Error::Transport);
         };
 
         match state.process_event(parse_auth_event(payload)).await {
-            Ok(AuthStates::AuthOk(result)) => return Ok(result.clone()),
+            Ok(AuthStates::AuthOk(key)) => return Ok(key.clone()),
             Err(AuthError::ActionFailed(err)) => {
                 error!(?err, "State machine action failed");
                 return Err(err);

server/crates/arbiter-server/src/actors/user_agent/auth/state.rs

@@ -0,0 +1,222 @@
+use arbiter_proto::transport::Bi;
+use diesel::{ExpressionMethods as _, OptionalExtension as _, QueryDsl, update};
+use diesel_async::RunQueryDsl;
+use tracing::error;
+
+use super::Error;
+use crate::{
+    actors::{
+        bootstrap::ConsumeToken,
+        user_agent::{AuthPublicKey, UserAgentConnection, auth::Outbound},
+    },
+    db::schema,
+};
+
+pub struct ChallengeRequest {
+    pub pubkey: AuthPublicKey,
+}
+
+pub struct BootstrapAuthRequest {
+    pub pubkey: AuthPublicKey,
+    pub token: String,
+}
+
+pub struct ChallengeContext {
+    pub challenge_nonce: i32,
+    pub key: AuthPublicKey,
+}
+
+pub struct ChallengeSolution {
+    pub solution: Vec<u8>,
+}
+
+smlang::statemachine!(
+    name: Auth,
+    custom_error: true,
+    transitions: {
+        *Init + AuthRequest(ChallengeRequest) / async prepare_challenge = SentChallenge(ChallengeContext),
+        Init + BootstrapAuthRequest(BootstrapAuthRequest) / async verify_bootstrap_token = AuthOk(AuthPublicKey),
+        SentChallenge(ChallengeContext) + ReceivedSolution(ChallengeSolution) / async verify_solution = AuthOk(AuthPublicKey),
+    }
+);
+
+async fn create_nonce(db: &crate::db::DatabasePool, pubkey_bytes: &[u8]) -> Result<i32, Error> {
+    let mut db_conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::internal("Database unavailable")
+    })?;
+    db_conn
+        .exclusive_transaction(|conn| {
+            Box::pin(async move {
+                let current_nonce = schema::useragent_client::table
+                    .filter(schema::useragent_client::public_key.eq(pubkey_bytes.to_vec()))
+                    .select(schema::useragent_client::nonce)
+                    .first::<i32>(conn)
+                    .await?;
+
+                update(schema::useragent_client::table)
+                    .filter(schema::useragent_client::public_key.eq(pubkey_bytes.to_vec()))
+                    .set(schema::useragent_client::nonce.eq(current_nonce + 1))
+                    .execute(conn)
+                    .await?;
+
+                Result::<_, diesel::result::Error>::Ok(current_nonce)
+            })
+        })
+        .await
+        .optional()
+        .map_err(|e| {
+            error!(error = ?e, "Database error");
+            Error::internal("Database operation failed")
+        })?
+        .ok_or_else(|| {
+            error!(?pubkey_bytes, "Public key not found in database");
+            Error::UnregisteredPublicKey
+        })
+}
+
+async fn register_key(db: &crate::db::DatabasePool, pubkey: &AuthPublicKey) -> Result<(), Error> {
+    let pubkey_bytes = pubkey.to_stored_bytes();
+    let key_type = pubkey.key_type();
+    let mut conn = db.get().await.map_err(|e| {
+        error!(error = ?e, "Database pool error");
+        Error::internal("Database unavailable")
+    })?;
+
+    diesel::insert_into(schema::useragent_client::table)
+        .values((
+            schema::useragent_client::public_key.eq(pubkey_bytes),
+            schema::useragent_client::nonce.eq(1),
+            schema::useragent_client::key_type.eq(key_type),
+        ))
+        .execute(&mut conn)
+        .await
+        .map_err(|e| {
+            error!(error = ?e, "Database error");
+            Error::internal("Database operation failed")
+        })?;
+
+    Ok(())
+}
+
+pub struct AuthContext<'a, T> {
+    pub(super) conn: &'a mut UserAgentConnection,
+    pub(super) transport: T,
+}
+
+impl<'a, T> AuthContext<'a, T> {
+    pub fn new(conn: &'a mut UserAgentConnection, transport: T) -> Self {
+        Self { conn, transport }
+    }
+}
+
+impl<T> AuthStateMachineContext for AuthContext<'_, T>
+where
+    T: Bi<super::Inbound, Result<super::Outbound, Error>> + Send,
+{
+    type Error = Error;
+
+    async fn prepare_challenge(
+        &mut self,
+        ChallengeRequest { pubkey }: ChallengeRequest,
+    ) -> Result<ChallengeContext, Self::Error> {
+        let stored_bytes = pubkey.to_stored_bytes();
+        let nonce = create_nonce(&self.conn.db, &stored_bytes).await?;
+
+        self.transport
+            .send(Ok(Outbound::AuthChallenge { nonce }))
+            .await
+            .map_err(|e| {
+                error!(?e, "Failed to send auth challenge");
+                Error::Transport
+            })?;
+
+        Ok(ChallengeContext {
+            challenge_nonce: nonce,
+            key: pubkey,
+        })
+    }
+
+    #[allow(missing_docs)]
+    #[allow(clippy::result_unit_err)]
+    async fn verify_bootstrap_token(
+        &mut self,
+        BootstrapAuthRequest { pubkey, token }: BootstrapAuthRequest,
+    ) -> Result<AuthPublicKey, Self::Error> {
+        let token_ok: bool = self
+            .conn
+            .actors
+            .bootstrapper
+            .ask(ConsumeToken {
+                token: token.clone(),
+            })
+            .await
+            .map_err(|e| {
+                error!(?e, "Failed to consume bootstrap token");
+                Error::internal("Failed to consume bootstrap token")
+            })?;
+
+        if !token_ok {
+            error!("Invalid bootstrap token provided");
+            return Err(Error::InvalidBootstrapToken);
+        }
+
+        register_key(&self.conn.db, &pubkey).await?;
+
+        self.transport
+            .send(Ok(Outbound::AuthSuccess))
+            .await
+            .map_err(|_| Error::Transport)?;
+
+        Ok(pubkey)
+    }
+
+    #[allow(missing_docs)]
+    #[allow(clippy::unused_unit)]
+    async fn verify_solution(
+        &mut self,
+        ChallengeContext {
+            challenge_nonce,
+            key,
+        }: &ChallengeContext,
+        ChallengeSolution { solution }: ChallengeSolution,
+    ) -> Result<AuthPublicKey, Self::Error> {
+        let formatted = arbiter_proto::format_challenge(*challenge_nonce, &key.to_stored_bytes());
+
+        let valid = match key {
+            AuthPublicKey::Ed25519(vk) => {
+                let sig = solution.as_slice().try_into().map_err(|_| {
+                    error!(?solution, "Invalid Ed25519 signature length");
+                    Error::InvalidChallengeSolution
+                })?;
+                vk.verify_strict(&formatted, &sig).is_ok()
+            }
+            AuthPublicKey::EcdsaSecp256k1(vk) => {
+                use k256::ecdsa::signature::Verifier as _;
+                let sig = k256::ecdsa::Signature::try_from(solution.as_slice()).map_err(|_| {
+                    error!(?solution, "Invalid ECDSA signature bytes");
+                    Error::InvalidChallengeSolution
+                })?;
+                vk.verify(&formatted, &sig).is_ok()
+            }
+            AuthPublicKey::Rsa(pk) => {
+                use rsa::signature::Verifier as _;
+                let verifying_key = rsa::pss::VerifyingKey::<sha2::Sha256>::new(pk.clone());
+                let sig = rsa::pss::Signature::try_from(solution.as_slice()).map_err(|_| {
+                    error!(?solution, "Invalid RSA signature bytes");
+                    Error::InvalidChallengeSolution
+                })?;
+                verifying_key.verify(&formatted, &sig).is_ok()
+            }
+        };
+
+        if valid {
+            self.transport
+                .send(Ok(Outbound::AuthSuccess))
+                .await
+                .map_err(|_| Error::Transport)?;
+        }
+
+        Ok(key.clone())
+    }
+}

server/crates/arbiter-server/src/actors/user_agent/mod.rs

@@ -0,0 +1,94 @@
+use crate::{
+    actors::{GlobalActors, client::ClientProfile},
+    db::{self, models::KeyType},
+};
+
+/// Abstraction over Ed25519 / ECDSA-secp256k1 / RSA public keys used during the auth handshake.
+#[derive(Clone, Debug)]
+pub enum AuthPublicKey {
+    Ed25519(ed25519_dalek::VerifyingKey),
+    /// Compressed SEC1 public key; signature bytes are raw 64-byte (r||s).
+    EcdsaSecp256k1(k256::ecdsa::VerifyingKey),
+    /// RSA-2048+ public key (Windows Hello / KeyCredentialManager); signature bytes are PSS+SHA-256.
+    Rsa(rsa::RsaPublicKey),
+}
+
+impl AuthPublicKey {
+    /// Canonical bytes stored in DB and echoed back in the challenge.
+    /// Ed25519: raw 32 bytes. ECDSA: SEC1 compressed 33 bytes. RSA: DER-encoded SPKI.
+    pub fn to_stored_bytes(&self) -> Vec<u8> {
+        match self {
+            AuthPublicKey::Ed25519(k) => k.to_bytes().to_vec(),
+            // SEC1 compressed (33 bytes) is the natural compact format for secp256k1
+            AuthPublicKey::EcdsaSecp256k1(k) => k.to_encoded_point(true).as_bytes().to_vec(),
+            AuthPublicKey::Rsa(k) => {
+                use rsa::pkcs8::EncodePublicKey as _;
+                #[allow(clippy::expect_used)]
+                k.to_public_key_der()
+                    .expect("rsa SPKI encoding is infallible")
+                    .to_vec()
+            }
+        }
+    }
+
+    pub fn key_type(&self) -> KeyType {
+        match self {
+            AuthPublicKey::Ed25519(_) => KeyType::Ed25519,
+            AuthPublicKey::EcdsaSecp256k1(_) => KeyType::EcdsaSecp256k1,
+            AuthPublicKey::Rsa(_) => KeyType::Rsa,
+        }
+    }
+}
+
+impl TryFrom<(KeyType, Vec<u8>)> for AuthPublicKey {
+    type Error = &'static str;
+
+    fn try_from(value: (KeyType, Vec<u8>)) -> Result<Self, Self::Error> {
+        let (key_type, bytes) = value;
+        match key_type {
+            KeyType::Ed25519 => {
+                let bytes: [u8; 32] = bytes.try_into().map_err(|_| "invalid Ed25519 key length")?;
+                let key = ed25519_dalek::VerifyingKey::from_bytes(&bytes)
+                    .map_err(|_e| "invalid Ed25519 key")?;
+                Ok(AuthPublicKey::Ed25519(key))
+            }
+            KeyType::EcdsaSecp256k1 => {
+                let point =
+                    k256::EncodedPoint::from_bytes(&bytes).map_err(|_e| "invalid ECDSA key")?;
+                let key = k256::ecdsa::VerifyingKey::from_encoded_point(&point)
+                    .map_err(|_e| "invalid ECDSA key")?;
+                Ok(AuthPublicKey::EcdsaSecp256k1(key))
+            }
+            KeyType::Rsa => {
+                use rsa::pkcs8::DecodePublicKey as _;
+                let key = rsa::RsaPublicKey::from_public_key_der(&bytes)
+                    .map_err(|_e| "invalid RSA key")?;
+                Ok(AuthPublicKey::Rsa(key))
+            }
+        }
+    }
+}
+
+// Messages, sent by user agent to connection client without having a request
+#[derive(Debug)]
+pub enum OutOfBand {
+    ClientConnectionRequest { profile: ClientProfile },
+    ClientConnectionCancel { pubkey: ed25519_dalek::VerifyingKey },
+}
+
+pub struct UserAgentConnection {
+    pub(crate) db: db::DatabasePool,
+    pub(crate) actors: GlobalActors,
+}
+
+impl UserAgentConnection {
+    pub fn new(db: db::DatabasePool, actors: GlobalActors) -> Self {
+        Self { db, actors }
+    }
+}
+
+pub mod auth;
+pub mod session;
+
+pub use auth::authenticate;
+pub use session::UserAgentSession;

server/crates/arbiter-server/src/actors/user_agent/session.rs

@@ -1,19 +1,21 @@
-use super::{OutOfBand, OperatorConnection};
-use crate::{
-    actors::{
-        flow_coordinator::client_connect_approval::ClientApprovalController,
-        operator_registry::ConnectOperator,
-    },
-    peers::client::ClientProfile,
-};
-use arbiter_crypto::authn;
-use arbiter_proto::transport::Sender;
-
-use kameo::{Actor, actor::ActorRef, messages};
 use std::{borrow::Cow, collections::HashMap};
+
+use arbiter_proto::transport::Sender;
+use async_trait::async_trait;
+use ed25519_dalek::VerifyingKey;
+use kameo::{Actor, actor::ActorRef, messages};
 use thiserror::Error;
 use tracing::error;
 
+use crate::actors::{
+    client::ClientProfile,
+    flow_coordinator::{RegisterUserAgent, client_connect_approval::ClientApprovalController},
+    user_agent::{OutOfBand, UserAgentConnection},
+};
+
+mod state;
+use state::{DummyContext, UserAgentEvents, UserAgentStateMachine};
+
 #[derive(Debug, Error)]
 pub enum Error {
     #[error("State transition failed")]
@@ -45,31 +47,56 @@ impl Error {
 }
 
 pub struct PendingClientApproval {
-    pubkey: authn::PublicKey,
     controller: ActorRef<ClientApprovalController>,
 }
 
-pub struct OperatorSession {
+pub struct UserAgentSession {
-    props: OperatorConnection,
+    props: UserAgentConnection,
+    state: UserAgentStateMachine<DummyContext>,
     sender: Box<dyn Sender<OutOfBand>>,
 
-    pending_client_approvals: HashMap<Vec<u8>, PendingClientApproval>,
+    pending_client_approvals: HashMap<VerifyingKey, PendingClientApproval>,
 }
 
-pub mod handlers;
+pub mod connection;
 
-impl OperatorSession {
+impl UserAgentSession {
-    pub(crate) fn new(props: OperatorConnection, sender: Box<dyn Sender<OutOfBand>>) -> Self {
+    pub(crate) fn new(props: UserAgentConnection, sender: Box<dyn Sender<OutOfBand>>) -> Self {
         Self {
             props,
+            state: UserAgentStateMachine::new(DummyContext),
             sender,
             pending_client_approvals: Default::default(),
         }
     }
+
+    pub fn new_test(db: crate::db::DatabasePool, actors: crate::actors::GlobalActors) -> Self {
+        struct DummySender;
+
+        #[async_trait]
+        impl Sender<OutOfBand> for DummySender {
+            async fn send(
+                &mut self,
+                _item: OutOfBand,
+            ) -> Result<(), arbiter_proto::transport::Error> {
+                Ok(())
+            }
+        }
+
+        Self::new(UserAgentConnection::new(db, actors), Box::new(DummySender))
+    }
+
+    fn transition(&mut self, event: UserAgentEvents) -> Result<(), Error> {
+        self.state.process_event(event).map_err(|e| {
+            error!(?e, "State transition failed");
+            Error::State
+        })?;
+        Ok(())
+    }
 }
 
 #[messages]
-impl OperatorSession {
+impl UserAgentSession {
     #[message]
     pub async fn begin_new_client_approval(
         &mut self,
@@ -85,41 +112,39 @@ impl OperatorSession {
         {
             error!(
                 ?e,
-                actor = "operator",
+                actor = "user_agent",
                 event = "failed to announce new client connection"
             );
             return;
         }
 
-        self.pending_client_approvals.insert(
+        self.pending_client_approvals
-            client.pubkey.to_bytes(),
+            .insert(client.pubkey, PendingClientApproval { controller });
-            PendingClientApproval {
-                pubkey: client.pubkey,
-                controller,
-            },
-        );
     }
 }
 
-impl Actor for OperatorSession {
+impl Actor for UserAgentSession {
     type Args = Self;
 
     type Error = Error;
 
-    async fn on_start(args: Self::Args, this: ActorRef<Self>) -> Result<Self, Self::Error> {
+    async fn on_start(
+        args: Self::Args,
+        this: kameo::prelude::ActorRef<Self>,
+    ) -> Result<Self, Self::Error> {
         args.props
             .actors
-            .operator_registry
+            .flow_coordinator
-            .ask(ConnectOperator {
+            .ask(RegisterUserAgent {
                 actor: this.clone(),
             })
             .await
             .map_err(|err| {
                 error!(
                     ?err,
-                    "Failed to register operator connection with operator registry"
+                    "Failed to register user agent connection with flow coordinator"
                 );
-                Error::internal("Failed to register operator connection with operator registry")
+                Error::internal("Failed to register user agent connection with flow coordinator")
             })?;
         Ok(args)
     }
@@ -133,23 +158,19 @@ impl Actor for OperatorSession {
         let cancelled_pubkey = self
             .pending_client_approvals
             .iter()
-            .find_map(|(k, v)| (v.controller.id() == id).then_some(k.clone()));
+            .find_map(|(k, v)| (v.controller.id() == id).then_some(*k));
 
-        if let Some(pubkey_bytes) = cancelled_pubkey {
+        if let Some(pubkey) = cancelled_pubkey {
-            let Some(approval) = self.pending_client_approvals.remove(&pubkey_bytes) else {
+            self.pending_client_approvals.remove(&pubkey);
-                return Ok(std::ops::ControlFlow::Continue(()));
-            };
 
             if let Err(e) = self
                 .sender
-                .send(OutOfBand::ClientConnectionCancel {
+                .send(OutOfBand::ClientConnectionCancel { pubkey })
-                    pubkey: approval.pubkey,
-                })
                 .await
             {
                 error!(
                     ?e,
-                    actor = "operator",
+                    actor = "user_agent",
                     event = "failed to announce client connection cancellation"
                 );
             }

server/crates/arbiter-server/src/actors/user_agent/session/connection.rs

@@ -0,0 +1,473 @@
+use std::sync::Mutex;
+
+use alloy::primitives::Address;
+use chacha20poly1305::{AeadInPlace, XChaCha20Poly1305, XNonce, aead::KeyInit};
+use diesel::sql_types::ops::Add;
+use diesel::{BoolExpressionMethods as _, ExpressionMethods as _, QueryDsl as _, SelectableHelper};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use kameo::error::SendError;
+use kameo::prelude::Context;
+use kameo::{message, messages};
+use tracing::{error, info};
+use x25519_dalek::{EphemeralSecret, PublicKey};
+
+use crate::actors::flow_coordinator::client_connect_approval::ClientApprovalAnswer;
+use crate::actors::keyholder::KeyHolderState;
+use crate::actors::user_agent::session::Error;
+use crate::db::models::{
+    CoreEvmWalletAccess, EvmWalletAccess, NewEvmWalletAccess, ProgramClient, ProgramClientMetadata,
+};
+use crate::db::schema::evm_wallet_access;
+use crate::evm::policies::{Grant, SpecificGrant};
+use crate::safe_cell::SafeCell;
+use crate::{
+    actors::{
+        evm::{
+            Generate, ListWallets, UseragentCreateGrant, UseragentDeleteGrant, UseragentListGrants,
+        },
+        keyholder::{self, Bootstrap, TryUnseal},
+        user_agent::session::{
+            UserAgentSession,
+            state::{UnsealContext, UserAgentEvents, UserAgentStates},
+        },
+    },
+    safe_cell::SafeCellHandle as _,
+};
+
+impl UserAgentSession {
+    fn take_unseal_secret(&mut self) -> Result<(EphemeralSecret, PublicKey), Error> {
+        let UserAgentStates::WaitingForUnsealKey(unseal_context) = self.state.state() else {
+            error!("Received encrypted key in invalid state");
+            return Err(Error::internal("Invalid state for unseal encrypted key"));
+        };
+
+        let ephemeral_secret = {
+            #[allow(
+                clippy::unwrap_used,
+                reason = "Mutex poison is unrecoverable and should panic"
+            )]
+            let mut secret_lock = unseal_context.secret.lock().unwrap();
+            let secret = secret_lock.take();
+            match secret {
+                Some(secret) => secret,
+                None => {
+                    drop(secret_lock);
+                    error!("Ephemeral secret already taken");
+                    return Err(Error::internal("Ephemeral secret already taken"));
+                }
+            }
+        };
+
+        Ok((ephemeral_secret, unseal_context.client_public_key))
+    }
+
+    fn decrypt_client_key_material(
+        ephemeral_secret: EphemeralSecret,
+        client_public_key: PublicKey,
+        nonce: &[u8],
+        ciphertext: &[u8],
+        associated_data: &[u8],
+    ) -> Result<SafeCell<Vec<u8>>, ()> {
+        let nonce = XNonce::from_slice(nonce);
+
+        let shared_secret = ephemeral_secret.diffie_hellman(&client_public_key);
+        let cipher = XChaCha20Poly1305::new(shared_secret.as_bytes().into());
+
+        let mut key_buffer = SafeCell::new(ciphertext.to_vec());
+
+        let decryption_result = key_buffer.write_inline(|write_handle| {
+            cipher.decrypt_in_place(nonce, associated_data, write_handle)
+        });
+
+        match decryption_result {
+            Ok(_) => Ok(key_buffer),
+            Err(err) => {
+                error!(?err, "Failed to decrypt encrypted key material");
+                Err(())
+            }
+        }
+    }
+}
+
+pub struct UnsealStartResponse {
+    pub server_pubkey: PublicKey,
+}
+
+#[derive(Debug, Error)]
+pub enum UnsealError {
+    #[error("Invalid key provided for unsealing")]
+    InvalidKey,
+    #[error("Internal error during unsealing process")]
+    General(#[from] super::Error),
+}
+
+#[derive(Debug, Error)]
+pub enum BootstrapError {
+    #[error("Invalid key provided for bootstrapping")]
+    InvalidKey,
+    #[error("Vault is already bootstrapped")]
+    AlreadyBootstrapped,
+
+    #[error("Internal error during bootstrapping process")]
+    General(#[from] super::Error),
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub async fn handle_unseal_request(
+        &mut self,
+        client_pubkey: x25519_dalek::PublicKey,
+    ) -> Result<UnsealStartResponse, Error> {
+        let secret = EphemeralSecret::random();
+        let public_key = PublicKey::from(&secret);
+
+        self.transition(UserAgentEvents::UnsealRequest(UnsealContext {
+            secret: Mutex::new(Some(secret)),
+            client_public_key: client_pubkey,
+        }))?;
+
+        Ok(UnsealStartResponse {
+            server_pubkey: public_key,
+        })
+    }
+
+    #[message]
+    pub async fn handle_unseal_encrypted_key(
+        &mut self,
+        nonce: Vec<u8>,
+        ciphertext: Vec<u8>,
+        associated_data: Vec<u8>,
+    ) -> Result<(), UnsealError> {
+        let (ephemeral_secret, client_public_key) = match self.take_unseal_secret() {
+            Ok(values) => values,
+            Err(Error::State) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                return Err(UnsealError::InvalidKey);
+            }
+            Err(_err) => {
+                return Err(Error::internal("Failed to take unseal secret").into());
+            }
+        };
+
+        let seal_key_buffer = match Self::decrypt_client_key_material(
+            ephemeral_secret,
+            client_public_key,
+            &nonce,
+            &ciphertext,
+            &associated_data,
+        ) {
+            Ok(buffer) => buffer,
+            Err(()) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                return Err(UnsealError::InvalidKey);
+            }
+        };
+
+        match self
+            .props
+            .actors
+            .key_holder
+            .ask(TryUnseal {
+                seal_key_raw: seal_key_buffer,
+            })
+            .await
+        {
+            Ok(_) => {
+                info!("Successfully unsealed key with client-provided key");
+                self.transition(UserAgentEvents::ReceivedValidKey)?;
+                Ok(())
+            }
+            Err(SendError::HandlerError(keyholder::Error::InvalidKey)) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(UnsealError::InvalidKey)
+            }
+            Err(SendError::HandlerError(err)) => {
+                error!(?err, "Keyholder failed to unseal key");
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(UnsealError::InvalidKey)
+            }
+            Err(err) => {
+                error!(?err, "Failed to send unseal request to keyholder");
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(Error::internal("Vault actor error").into())
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_bootstrap_encrypted_key(
+        &mut self,
+        nonce: Vec<u8>,
+        ciphertext: Vec<u8>,
+        associated_data: Vec<u8>,
+    ) -> Result<(), BootstrapError> {
+        let (ephemeral_secret, client_public_key) = match self.take_unseal_secret() {
+            Ok(values) => values,
+            Err(Error::State) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                return Err(BootstrapError::InvalidKey);
+            }
+            Err(err) => return Err(err.into()),
+        };
+
+        let seal_key_buffer = match Self::decrypt_client_key_material(
+            ephemeral_secret,
+            client_public_key,
+            &nonce,
+            &ciphertext,
+            &associated_data,
+        ) {
+            Ok(buffer) => buffer,
+            Err(()) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                return Err(BootstrapError::InvalidKey);
+            }
+        };
+
+        match self
+            .props
+            .actors
+            .key_holder
+            .ask(Bootstrap {
+                seal_key_raw: seal_key_buffer,
+            })
+            .await
+        {
+            Ok(_) => {
+                info!("Successfully bootstrapped vault with client-provided key");
+                self.transition(UserAgentEvents::ReceivedValidKey)?;
+                Ok(())
+            }
+            Err(SendError::HandlerError(keyholder::Error::AlreadyBootstrapped)) => {
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(BootstrapError::AlreadyBootstrapped)
+            }
+            Err(SendError::HandlerError(err)) => {
+                error!(?err, "Keyholder failed to bootstrap vault");
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(BootstrapError::InvalidKey)
+            }
+            Err(err) => {
+                error!(?err, "Failed to send bootstrap request to keyholder");
+                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
+                Err(BootstrapError::General(Error::internal(
+                    "Vault actor error",
+                )))
+            }
+        }
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub(crate) async fn handle_query_vault_state(&mut self) -> Result<KeyHolderState, Error> {
+        use crate::actors::keyholder::GetState;
+
+        let vault_state = match self.props.actors.key_holder.ask(GetState {}).await {
+            Ok(state) => state,
+            Err(err) => {
+                error!(?err, actor = "useragent", "keyholder.query.failed");
+                return Err(Error::internal("Vault is in broken state"));
+            }
+        };
+
+        Ok(vault_state)
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub(crate) async fn handle_evm_wallet_create(&mut self) -> Result<(i32, Address), Error> {
+        match self.props.actors.evm.ask(Generate {}).await {
+            Ok(address) => Ok(address),
+            Err(SendError::HandlerError(err)) => Err(Error::internal(format!(
+                "EVM wallet generation failed: {err}"
+            ))),
+            Err(err) => {
+                error!(?err, "EVM actor unreachable during wallet create");
+                Err(Error::internal("EVM actor unreachable"))
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_evm_wallet_list(&mut self) -> Result<Vec<(i32, Address)>, Error> {
+        match self.props.actors.evm.ask(ListWallets {}).await {
+            Ok(wallets) => Ok(wallets),
+            Err(err) => {
+                error!(?err, "EVM wallet list failed");
+                Err(Error::internal("Failed to list EVM wallets"))
+            }
+        }
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message]
+    pub(crate) async fn handle_grant_list(&mut self) -> Result<Vec<Grant<SpecificGrant>>, Error> {
+        match self.props.actors.evm.ask(UseragentListGrants {}).await {
+            Ok(grants) => Ok(grants),
+            Err(err) => {
+                error!(?err, "EVM grant list failed");
+                Err(Error::internal("Failed to list EVM grants"))
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_grant_create(
+        &mut self,
+        basic: crate::evm::policies::SharedGrantSettings,
+        grant: crate::evm::policies::SpecificGrant,
+    ) -> Result<i32, Error> {
+        match self
+            .props
+            .actors
+            .evm
+            .ask(UseragentCreateGrant { basic, grant })
+            .await
+        {
+            Ok(grant_id) => Ok(grant_id),
+            Err(err) => {
+                error!(?err, "EVM grant create failed");
+                Err(Error::internal("Failed to create EVM grant"))
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_grant_delete(&mut self, grant_id: i32) -> Result<(), Error> {
+        match self
+            .props
+            .actors
+            .evm
+            .ask(UseragentDeleteGrant { grant_id })
+            .await
+        {
+            Ok(()) => Ok(()),
+            Err(err) => {
+                error!(?err, "EVM grant delete failed");
+                Err(Error::internal("Failed to delete EVM grant"))
+            }
+        }
+    }
+
+    #[message]
+    pub(crate) async fn handle_grant_evm_wallet_access(
+        &mut self,
+        entries: Vec<NewEvmWalletAccess>,
+    ) -> Result<(), Error> {
+        let mut conn = self.props.db.get().await?;
+        conn.transaction(|conn| {
+            Box::pin(async move {
+                use crate::db::schema::evm_wallet_access;
+
+                for entry in entries {
+                    diesel::insert_into(evm_wallet_access::table)
+                        .values(&entry)
+                        .on_conflict_do_nothing()
+                        .execute(conn)
+                        .await?;
+                }
+
+                Result::<_, Error>::Ok(())
+            })
+        })
+        .await?;
+        Ok(())
+    }
+
+    #[message]
+    pub(crate) async fn handle_revoke_evm_wallet_access(
+        &mut self,
+        entries: Vec<i32>,
+    ) -> Result<(), Error> {
+        let mut conn = self.props.db.get().await?;
+        conn.transaction(|conn| {
+            Box::pin(async move {
+                use crate::db::schema::evm_wallet_access;
+                for entry in entries {
+                    diesel::delete(evm_wallet_access::table)
+                        .filter(evm_wallet_access::wallet_id.eq(entry))
+                        .execute(conn)
+                        .await?;
+                }
+
+                Result::<_, Error>::Ok(())
+            })
+        })
+        .await?;
+        Ok(())
+    }
+
+    #[message]
+    pub(crate) async fn handle_list_wallet_access(
+        &mut self,
+    ) -> Result<Vec<EvmWalletAccess>, Error> {
+        let mut conn = self.props.db.get().await?;
+        use crate::db::schema::evm_wallet_access;
+        let access_entries = evm_wallet_access::table
+            .select(EvmWalletAccess::as_select())
+            .load::<_>(&mut conn)
+            .await?;
+        Ok(access_entries)
+    }
+}
+
+#[messages]
+impl UserAgentSession {
+    #[message(ctx)]
+    pub(crate) async fn handle_new_client_approve(
+        &mut self,
+        approved: bool,
+        pubkey: ed25519_dalek::VerifyingKey,
+        ctx: &mut Context<Self, Result<(), Error>>,
+    ) -> Result<(), Error> {
+        let pending_approval = match self.pending_client_approvals.remove(&pubkey) {
+            Some(approval) => approval,
+            None => {
+                error!("Received client connection response for unknown client");
+                return Err(Error::internal("Unknown client in connection response"));
+            }
+        };
+
+        pending_approval
+            .controller
+            .tell(ClientApprovalAnswer { approved })
+            .await
+            .map_err(|err| {
+                error!(
+                    ?err,
+                    "Failed to send client approval response to controller"
+                );
+                Error::internal("Failed to send client approval response to controller")
+            })?;
+
+        ctx.actor_ref().unlink(&pending_approval.controller).await;
+
+        Ok(())
+    }
+
+    #[message]
+    pub(crate) async fn handle_sdk_client_list(
+        &mut self,
+    ) -> Result<Vec<(ProgramClient, ProgramClientMetadata)>, Error> {
+        use crate::db::schema::{client_metadata, program_client};
+        let mut conn = self.props.db.get().await?;
+
+        let clients = program_client::table
+            .inner_join(client_metadata::table)
+            .select((
+                ProgramClient::as_select(),
+                ProgramClientMetadata::as_select(),
+            ))
+            .load::<(ProgramClient, ProgramClientMetadata)>(&mut conn)
+            .await?;
+
+        Ok(clients)
+    }
+}

server/crates/arbiter-server/src/actors/user_agent/session/state.rs

@@ -0,0 +1,27 @@
+use std::sync::Mutex;
+
+use x25519_dalek::{EphemeralSecret, PublicKey};
+
+pub struct UnsealContext {
+    pub client_public_key: PublicKey,
+    pub secret: Mutex<Option<EphemeralSecret>>,
+}
+
+smlang::statemachine!(
+    name: UserAgent,
+    custom_error: false,
+    transitions: {
+        *Idle + UnsealRequest(UnsealContext) / generate_temp_keypair = WaitingForUnsealKey(UnsealContext),
+        WaitingForUnsealKey(UnsealContext) + ReceivedValidKey = Unsealed,
+        WaitingForUnsealKey(UnsealContext) + ReceivedInvalidKey = Idle,
+    }
+);
+
+pub struct DummyContext;
+impl UserAgentStateMachineContext for DummyContext {
+    #[allow(missing_docs)]
+    #[allow(clippy::unused_unit)]
+    fn generate_temp_keypair(&mut self, event_data: UnsealContext) -> Result<UnsealContext, ()> {
+        Ok(event_data)
+    }
+}

server/crates/arbiter-server/src/cli.rs

@@ -0,0 +1,72 @@
+use std::{
+    net::{Ipv4Addr, SocketAddr, SocketAddrV4},
+    path::PathBuf,
+};
+
+use clap::{Args, Parser, Subcommand};
+
+const DEFAULT_LISTEN_ADDR: SocketAddr = SocketAddr::V4(SocketAddrV4::new(
+    Ipv4Addr::LOCALHOST,
+    arbiter_proto::DEFAULT_SERVER_PORT,
+));
+
+#[derive(Debug, Parser)]
+#[command(name = "arbiter-server")]
+#[command(about = "Arbiter gRPC server")]
+pub struct Cli {
+    #[command(subcommand)]
+    pub command: Option<Command>,
+}
+
+#[derive(Debug, Subcommand)]
+pub enum Command {
+    /// Run server in foreground mode.
+    Run(RunArgs),
+    /// Manage service lifecycle.
+    Service {
+        #[command(subcommand)]
+        command: ServiceCommand,
+    },
+}
+
+#[derive(Debug, Clone, Args)]
+pub struct RunArgs {
+    #[arg(long, default_value_t = DEFAULT_LISTEN_ADDR)]
+    pub listen_addr: SocketAddr,
+    #[arg(long)]
+    pub data_dir: Option<PathBuf>,
+}
+
+impl Default for RunArgs {
+    fn default() -> Self {
+        Self {
+            listen_addr: DEFAULT_LISTEN_ADDR,
+            data_dir: None,
+        }
+    }
+}
+
+#[derive(Debug, Subcommand)]
+pub enum ServiceCommand {
+    /// Install Windows service in Service Control Manager.
+    Install(ServiceInstallArgs),
+    /// Internal service entrypoint. SCM only.
+    #[command(hide = true)]
+    Run(ServiceRunArgs),
+}
+
+#[derive(Debug, Clone, Args)]
+pub struct ServiceInstallArgs {
+    #[arg(long)]
+    pub start: bool,
+    #[arg(long)]
+    pub data_dir: Option<PathBuf>,
+}
+
+#[derive(Debug, Clone, Args)]
+pub struct ServiceRunArgs {
+    #[arg(long, default_value_t = DEFAULT_LISTEN_ADDR)]
+    pub listen_addr: SocketAddr,
+    #[arg(long)]
+    pub data_dir: Option<PathBuf>,
+}

server/crates/arbiter-server/src/context/mod.rs

@@ -1,45 +1,53 @@
+use std::sync::Arc;
+
+use miette::Diagnostic;
+use thiserror::Error;
+
 use crate::{
     actors::GlobalActors,
     context::tls::TlsManager,
     db::{self},
 };
 
-use std::sync::Arc;
-use thiserror::Error;
-
 pub mod tls;
 
-#[derive(Error, Debug)]
+#[derive(Error, Debug, Diagnostic)]
 pub enum InitError {
     #[error("Database setup failed: {0}")]
+    #[diagnostic(code(arbiter_server::init::database_setup))]
     DatabaseSetup(#[from] db::DatabaseSetupError),
 
     #[error("Connection acquire failed: {0}")]
+    #[diagnostic(code(arbiter_server::init::database_pool))]
     DatabasePool(#[from] db::PoolError),
 
     #[error("Database query error: {0}")]
+    #[diagnostic(code(arbiter_server::init::database_query))]
     DatabaseQuery(#[from] diesel::result::Error),
 
     #[error("TLS initialization failed: {0}")]
+    #[diagnostic(code(arbiter_server::init::tls_init))]
     Tls(#[from] tls::InitError),
 
     #[error("Actor spawn failed: {0}")]
+    #[diagnostic(code(arbiter_server::init::actor_spawn))]
     ActorSpawn(#[from] crate::actors::SpawnError),
 
     #[error("I/O Error: {0}")]
+    #[diagnostic(code(arbiter_server::init::io))]
     Io(#[from] std::io::Error),
 }
 
-pub struct __ServerContextInner {
+pub struct _ServerContextInner {
     pub db: db::DatabasePool,
     pub tls: TlsManager,
     pub actors: GlobalActors,
 }
 #[derive(Clone)]
-pub struct ServerContext(Arc<__ServerContextInner>);
+pub struct ServerContext(Arc<_ServerContextInner>);
 
 impl std::ops::Deref for ServerContext {
-    type Target = __ServerContextInner;
+    type Target = _ServerContextInner;
 
     fn deref(&self) -> &Self::Target {
         &self.0
@@ -48,7 +56,7 @@ impl std::ops::Deref for ServerContext {
 
 impl ServerContext {
     pub async fn new(db: db::DatabasePool) -> Result<Self, InitError> {
-        Ok(Self(Arc::new(__ServerContextInner {
+        Ok(Self(Arc::new(_ServerContextInner {
             actors: GlobalActors::spawn(db.clone()).await?,
             tls: TlsManager::new(db.clone()).await?,
             db,

server/crates/arbiter-server/src/context/tls.rs

@@ -1,3 +1,17 @@
+use std::{net::IpAddr, string::FromUtf8Error};
+
+use diesel::{ExpressionMethods as _, QueryDsl, SelectableHelper as _};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use miette::Diagnostic;
+use pem::Pem;
+use rcgen::{
+    BasicConstraints, Certificate, CertificateParams, CertifiedIssuer, DistinguishedName, DnType,
+    IsCa, Issuer, KeyPair, KeyUsagePurpose, SanType,
+};
+use rustls::pki_types::pem::PemObject;
+use thiserror::Error;
+use tonic::transport::CertificateDer;
+
 use crate::db::{
     self,
     models::{NewTlsHistory, TlsHistory},
@@ -7,58 +21,48 @@ use crate::db::{
     },
 };
 
-use diesel::{ExpressionMethods as _, QueryDsl, SelectableHelper as _};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use pem::Pem;
-use rcgen::{
-    BasicConstraints, Certificate, CertificateParams, CertifiedIssuer, DistinguishedName, DnType,
-    IsCa, Issuer, KeyPair, KeyUsagePurpose, SanType,
-};
-use rustls::pki_types::pem::PemObject;
-use std::{net::Ipv4Addr, string::FromUtf8Error};
-use thiserror::Error;
-use tonic::transport::CertificateDer;
-
 const ENCODE_CONFIG: pem::EncodeConfig = {
-    let line_ending = if cfg!(target_family = "windows") {
+    let line_ending = match cfg!(target_family = "windows") {
-        pem::LineEnding::CRLF
+        true => pem::LineEnding::CRLF,
-    } else {
+        false => pem::LineEnding::LF,
-        pem::LineEnding::LF
     };
     pem::EncodeConfig::new().set_line_ending(line_ending)
 };
 
-#[derive(Error, Debug)]
+#[derive(Error, Debug, Diagnostic)]
 pub enum InitError {
     #[error("Key generation error during TLS initialization: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::key_generation))]
     KeyGeneration(#[from] rcgen::Error),
 
     #[error("Key invalid format: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::key_invalid_format))]
     KeyInvalidFormat(#[from] FromUtf8Error),
 
     #[error("Key deserialization error: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::key_deserialization))]
     KeyDeserializationError(rcgen::Error),
 
     #[error("Database error during TLS initialization: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::database_error))]
     DatabaseError(#[from] diesel::result::Error),
 
     #[error("Pem deserialization error during TLS initialization: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::pem_deserialization))]
     PemDeserializationError(#[from] rustls::pki_types::pem::Error),
 
     #[error("Database pool acquire error during TLS initialization: {0}")]
+    #[diagnostic(code(arbiter_server::tls_init::database_pool_acquire))]
     DatabasePoolAcquire(#[from] db::PoolError),
 }
 
 pub type PemCert = String;
 
-pub fn encode_cert_to_pem(cert: &CertificateDer<'_>) -> PemCert {
+pub fn encode_cert_to_pem(cert: &CertificateDer) -> PemCert {
     pem::encode_config(&Pem::new("CERTIFICATE", cert.to_vec()), ENCODE_CONFIG)
 }
 
-#[expect(
+#[allow(unused)]
-    unused,
-    reason = "may be needed for future cert rotation implementation"
-)]
 struct SerializedTls {
     cert_pem: PemCert,
     cert_key_pem: String,
@@ -87,7 +91,7 @@ impl TlsCa {
 
         let cert_key_pem = certified_issuer.key().serialize_pem();
 
-        #[expect(
+        #[allow(
             clippy::unwrap_used,
             reason = "Broken cert couldn't bootstrap server anyway"
         )]
@@ -112,7 +116,9 @@ impl TlsCa {
         ];
         params
             .subject_alt_names
-            .push(SanType::IpAddress(Ipv4Addr::LOCALHOST.into()));
+            .push(SanType::IpAddress(IpAddr::from([
+                127, 0, 0, 1,
+            ])));
 
         let mut dn = DistinguishedName::new();
         dn.push(DnType::CommonName, "Arbiter Instance Leaf");
@@ -126,11 +132,7 @@ impl TlsCa {
         })
     }
 
-    #[expect(
+    #[allow(unused)]
-        unused,
-        clippy::unnecessary_wraps,
-        reason = "may be needed for future cert rotation implementation"
-    )]
     fn serialize(&self) -> Result<SerializedTls, InitError> {
         let cert_key_pem = self.issuer.key().serialize_pem();
         Ok(SerializedTls {
@@ -139,10 +141,7 @@ impl TlsCa {
         })
     }
 
-    #[expect(
+    #[allow(unused)]
-        unused,
-        reason = "may be needed for future cert rotation implementation"
-    )]
     fn try_deserialize(cert_pem: &str, cert_key_pem: &str) -> Result<Self, InitError> {
         let keypair =
             KeyPair::from_pem(cert_key_pem).map_err(InitError::KeyDeserializationError)?;
@@ -243,10 +242,10 @@ impl TlsManager {
         }
     }
 
-    pub const fn cert(&self) -> &CertificateDer<'static> {
+    pub fn cert(&self) -> &CertificateDer<'static> {
         &self.cert
     }
-    pub const fn ca_cert(&self) -> &CertificateDer<'static> {
+    pub fn ca_cert(&self) -> &CertificateDer<'static> {
         &self.ca_cert
     }
 

server/crates/arbiter-server/src/crypto/encryption/mod.rs

@@ -1,3 +0,0 @@
-pub mod v1;
-
-pub use v1::*;

server/crates/arbiter-server/src/crypto/encryption/v1.rs

@@ -1,102 +0,0 @@
-use argon2::password_hash::Salt as ArgonSalt;
-use rand::{
-    Rng as _, SeedableRng,
-    rngs::{StdRng, SysRng},
-};
-
-pub const ROOT_KEY_TAG: &[u8] = b"arbiter/seal/v1";
-pub const TAG: &[u8] = b"arbiter/private-key/v1";
-
-pub const NONCE_LENGTH: usize = 24;
-
-#[derive(Default)]
-pub struct Nonce(pub [u8; NONCE_LENGTH]);
-impl Nonce {
-    pub fn increment(&mut self) {
-        for i in (0..self.0.len()).rev() {
-            if let Some(byte) = self.0.get_mut(i) {
-                if *byte == 0xFF {
-                    *byte = 0;
-                } else {
-                    *byte += 1;
-                    break;
-                }
-            }
-        }
-    }
-
-    pub fn to_vec(&self) -> Vec<u8> {
-        self.0.to_vec()
-    }
-}
-impl<'a> TryFrom<&'a [u8]> for Nonce {
-    type Error = ();
-
-    fn try_from(value: &'a [u8]) -> Result<Self, Self::Error> {
-        if value.len() != NONCE_LENGTH {
-            return Err(());
-        }
-        let mut nonce = [0u8; NONCE_LENGTH];
-        nonce.copy_from_slice(value);
-        Ok(Self(nonce))
-    }
-}
-
-pub type Salt = [u8; ArgonSalt::RECOMMENDED_LENGTH];
-
-pub fn generate_salt() -> Salt {
-    let mut salt = Salt::default();
-    let mut rng =
-        StdRng::try_from_rng(&mut SysRng).expect("Rng failure is unrecoverable and should panic");
-    rng.fill_bytes(&mut salt);
-    salt
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::crypto::derive_key;
-    use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-    #[test]
-    fn derive_seal_key_deterministic() {
-        static PASSWORD: &[u8] = b"password";
-        let password = SafeCell::new(PASSWORD.to_vec());
-        let password2 = SafeCell::new(PASSWORD.to_vec());
-        let salt = generate_salt();
-
-        let mut key1 = derive_key(password, &salt);
-        let mut key2 = derive_key(password2, &salt);
-
-        let key1_reader = key1.0.read();
-        let key2_reader = key2.0.read();
-
-        assert_eq!(&*key1_reader, &*key2_reader);
-    }
-
-    #[test]
-    fn successful_derive() {
-        static PASSWORD: &[u8] = b"password";
-        let password = SafeCell::new(PASSWORD.to_vec());
-        let salt = generate_salt();
-
-        let mut key = derive_key(password, &salt);
-        let key_reader = key.0.read();
-
-        assert_ne!(key_reader.as_slice(), &[0u8; 32][..]);
-    }
-
-    #[test]
-    // We should fuzz this
-    pub fn nonce_increment() {
-        let mut nonce = Nonce([0u8; NONCE_LENGTH]);
-        nonce.increment();
-
-        assert_eq!(
-            nonce.0,
-            [
-                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
-            ]
-        );
-    }
-}

server/crates/arbiter-server/src/crypto/integrity/mod.rs

@@ -1,3 +0,0 @@
-pub mod v1;
-
-pub use v1::*;

server/crates/arbiter-server/src/crypto/integrity/v1.rs

@@ -1,334 +0,0 @@
-use crate::{
-    actors::vault::{self, GetState, SignIntegrity, Vault, VerifyIntegrity},
-    db::{
-        self,
-        models::{IntegrityEnvelope, NewIntegrityEnvelope},
-        schema::integrity_envelope,
-    },
-};
-use arbiter_crypto::hashing::Hashable;
-
-use diesel::{ExpressionMethods as _, QueryDsl, dsl::insert_into, sqlite::Sqlite};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use hmac::Hmac;
-use kameo::{actor::ActorRef, error::SendError};
-use sha2::{Digest as _, Sha256};
-
-#[derive(Debug, thiserror::Error)]
-pub enum Error {
-    #[error("Database error: {0}")]
-    Database(#[from] db::DatabaseError),
-
-    #[error("Vault error: {0}")]
-    Vault(#[from] vault::Error),
-
-    #[error("Vault mailbox error")]
-    VaultSend,
-
-    #[error("Integrity envelope is missing for entity {entity_kind}")]
-    MissingEnvelope { entity_kind: &'static str },
-
-    #[error(
-        "Integrity payload version mismatch for entity {entity_kind}: expected {expected}, found {found}"
-    )]
-    PayloadVersionMismatch {
-        entity_kind: &'static str,
-        expected: i32,
-        found: i32,
-    },
-
-    #[error("Integrity MAC mismatch for entity {entity_kind}")]
-    MacMismatch { entity_kind: &'static str },
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub enum AttestationStatus {
-    Attested,
-    Unavailable,
-}
-
-pub const CURRENT_PAYLOAD_VERSION: i32 = 1;
-pub const INTEGRITY_SUBKEY_TAG: &[u8] = b"arbiter/db-integrity-key/v1";
-
-pub type HmacSha256 = Hmac<Sha256>;
-
-pub trait Integrable: Hashable {
-    const KIND: &'static str;
-    const VERSION: i32 = 1;
-}
-
-fn payload_hash(payload: &impl Hashable) -> [u8; 32] {
-    let mut hasher = Sha256::new();
-    payload.hash(&mut hasher);
-    hasher.finalize().into()
-}
-
-fn push_len_prefixed(out: &mut Vec<u8>, bytes: &[u8]) {
-    #[expect(
-        clippy::cast_possible_truncation,
-        clippy::as_conversions,
-        reason = "fixme! #85"
-    )]
-    out.extend_from_slice(&(bytes.len() as u32).to_be_bytes());
-    out.extend_from_slice(bytes);
-}
-
-fn build_mac_input(
-    entity_kind: &str,
-    entity_id: &[u8],
-    payload_version: i32,
-    payload_hash: &[u8; 32],
-) -> Vec<u8> {
-    let mut out = Vec::with_capacity(8 + entity_kind.len() + entity_id.len() + 32);
-    push_len_prefixed(&mut out, entity_kind.as_bytes());
-    push_len_prefixed(&mut out, entity_id);
-    out.extend_from_slice(&payload_version.to_be_bytes());
-    out.extend_from_slice(payload_hash);
-    out
-}
-
-pub trait IntoId {
-    fn into_id(self) -> Vec<u8>;
-}
-
-impl IntoId for i32 {
-    fn into_id(self) -> Vec<u8> {
-        self.to_be_bytes().to_vec()
-    }
-}
-
-impl IntoId for &'_ [u8] {
-    fn into_id(self) -> Vec<u8> {
-        self.to_vec()
-    }
-}
-
-pub async fn sign_entity<E: Integrable>(
-    conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    vault: &ActorRef<Vault>,
-    entity: &E,
-    entity_id: impl IntoId,
-) -> Result<(), Error> {
-    let payload_hash = payload_hash(&entity);
-
-    let entity_id = entity_id.into_id();
-
-    let mac_input = build_mac_input(E::KIND, &entity_id, E::VERSION, &payload_hash);
-
-    let (key_version, mac) =
-        vault
-            .ask(SignIntegrity { mac_input })
-            .await
-            .map_err(|err| match err {
-                SendError::HandlerError(inner) => Error::Vault(inner),
-                _ => Error::VaultSend,
-            })?;
-
-    insert_into(integrity_envelope::table)
-        .values(NewIntegrityEnvelope {
-            entity_kind: E::KIND.to_owned(),
-            entity_id,
-            payload_version: E::VERSION,
-            key_version,
-            mac: mac.clone(),
-        })
-        .on_conflict((
-            integrity_envelope::entity_id,
-            integrity_envelope::entity_kind,
-        ))
-        .do_update()
-        .set((
-            integrity_envelope::payload_version.eq(E::VERSION),
-            integrity_envelope::key_version.eq(key_version),
-            integrity_envelope::mac.eq(mac),
-        ))
-        .execute(conn)
-        .await
-        .map_err(db::DatabaseError::from)?;
-
-    Ok(())
-}
-
-pub async fn verify_entity<E: Integrable>(
-    conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    vault: &ActorRef<Vault>,
-    entity: &E,
-    entity_id: impl IntoId,
-) -> Result<AttestationStatus, Error> {
-    let entity_id = entity_id.into_id();
-    let envelope: IntegrityEnvelope = integrity_envelope::table
-        .filter(integrity_envelope::entity_kind.eq(E::KIND))
-        .filter(integrity_envelope::entity_id.eq(&entity_id))
-        .first(conn)
-        .await
-        .map_err(|err| match err {
-            diesel::result::Error::NotFound => Error::MissingEnvelope {
-                entity_kind: E::KIND,
-            },
-            other => Error::Database(db::DatabaseError::from(other)),
-        })?;
-
-    if envelope.payload_version != E::VERSION {
-        return Err(Error::PayloadVersionMismatch {
-            entity_kind: E::KIND,
-            expected: E::VERSION,
-            found: envelope.payload_version,
-        });
-    }
-
-    let payload_hash = payload_hash(&entity);
-    let mac_input = build_mac_input(E::KIND, &entity_id, envelope.payload_version, &payload_hash);
-
-    let result = vault
-        .ask(VerifyIntegrity {
-            mac_input,
-            expected_mac: envelope.mac,
-            key_version: envelope.key_version,
-        })
-        .await;
-
-    match result {
-        Ok(true) => Ok(AttestationStatus::Attested),
-        Ok(false) => Err(Error::MacMismatch {
-            entity_kind: E::KIND,
-        }),
-        Err(SendError::HandlerError(vault::Error::Sealed)) => Ok(AttestationStatus::Unavailable),
-        Err(_) => Err(Error::VaultSend),
-    }
-}
-
-pub async fn is_signing_available(vault: &ActorRef<Vault>) -> Result<bool, Error> {
-    let state = vault.ask(GetState).await.map_err(|_| Error::VaultSend)?;
-    Ok(matches!(state, vault::VaultState::Unsealed))
-}
-
-#[cfg(test)]
-mod tests {
-    use diesel::{ExpressionMethods as _, QueryDsl};
-    use diesel_async::RunQueryDsl;
-    use kameo::{actor::ActorRef, prelude::Spawn};
-
-    use crate::{
-        actors::{
-            GlobalActors,
-            vault::{Bootstrap, Vault},
-        },
-        db::{self, schema},
-    };
-    use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-    use super::{Error, Integrable, sign_entity, verify_entity};
-    #[derive(Clone, arbiter_macros::Hashable)]
-    struct DummyEntity {
-        payload_version: i32,
-        payload: Vec<u8>,
-    }
-    impl Integrable for DummyEntity {
-        const KIND: &'static str = "dummy_entity";
-    }
-
-    async fn bootstrapped_vault(db: &db::DatabasePool) -> ActorRef<Vault> {
-        let actor = Vault::spawn(
-            Vault::new(db.clone(), GlobalActors::spawn_message_bus())
-                .await
-                .unwrap(),
-        );
-        actor
-            .ask(Bootstrap {
-                seal_key_raw: SafeCell::new(b"integrity-test-seal-key".to_vec()),
-            })
-            .await
-            .unwrap();
-        actor
-    }
-
-    #[tokio::test]
-    async fn sign_writes_envelope_and_verify_passes() {
-        const ENTITY_ID: &[u8] = b"entity-id-7";
-
-        let db = db::create_test_pool().await;
-        let vault = bootstrapped_vault(&db).await;
-        let mut conn = db.get().await.unwrap();
-
-        let entity = DummyEntity {
-            payload_version: 1,
-            payload: b"payload-v1".to_vec(),
-        };
-
-        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
-            .await
-            .unwrap();
-
-        let count: i64 = schema::integrity_envelope::table
-            .filter(schema::integrity_envelope::entity_kind.eq("dummy_entity"))
-            .filter(schema::integrity_envelope::entity_id.eq(ENTITY_ID))
-            .count()
-            .get_result(&mut conn)
-            .await
-            .unwrap();
-
-        assert_eq!(count, 1, "envelope row must be created exactly once");
-        verify_entity(&mut conn, &vault, &entity, ENTITY_ID)
-            .await
-            .unwrap();
-    }
-
-    #[tokio::test]
-    async fn tampered_mac_fails_verification() {
-        const ENTITY_ID: &[u8] = b"entity-id-11";
-
-        let db = db::create_test_pool().await;
-        let vault = bootstrapped_vault(&db).await;
-        let mut conn = db.get().await.unwrap();
-
-        let entity = DummyEntity {
-            payload_version: 1,
-            payload: b"payload-v1".to_vec(),
-        };
-
-        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
-            .await
-            .unwrap();
-
-        diesel::update(schema::integrity_envelope::table)
-            .filter(schema::integrity_envelope::entity_kind.eq("dummy_entity"))
-            .filter(schema::integrity_envelope::entity_id.eq(ENTITY_ID))
-            .set(schema::integrity_envelope::mac.eq(vec![0u8; 32]))
-            .execute(&mut conn)
-            .await
-            .unwrap();
-
-        let err = verify_entity(&mut conn, &vault, &entity, ENTITY_ID)
-            .await
-            .unwrap_err();
-        assert!(matches!(err, Error::MacMismatch { .. }));
-    }
-
-    #[tokio::test]
-    async fn changed_payload_fails_verification() {
-        const ENTITY_ID: &[u8] = b"entity-id-21";
-
-        let db = db::create_test_pool().await;
-        let vault = bootstrapped_vault(&db).await;
-        let mut conn = db.get().await.unwrap();
-
-        let entity = DummyEntity {
-            payload_version: 1,
-            payload: b"payload-v1".to_vec(),
-        };
-
-        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
-            .await
-            .unwrap();
-
-        let tampered = DummyEntity {
-            payload: b"payload-v1-but-tampered".to_vec(),
-            ..entity
-        };
-
-        let err = verify_entity(&mut conn, &vault, &tampered, ENTITY_ID)
-            .await
-            .unwrap_err();
-        assert!(matches!(err, Error::MacMismatch { .. }));
-    }
-}

server/crates/arbiter-server/src/crypto/mod.rs

@@ -1,155 +0,0 @@
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-use encryption::v1::{Nonce, Salt};
-
-use argon2::{Algorithm, Argon2};
-use chacha20poly1305::{
-    AeadInPlace, Key, KeyInit as _, XChaCha20Poly1305, XNonce,
-    aead::{AeadMut, Error, Payload},
-};
-use rand::{
-    Rng as _, SeedableRng as _,
-    rngs::{StdRng, SysRng},
-};
-
-pub mod encryption;
-pub mod integrity;
-
-pub struct KeyCell(pub SafeCell<Key>);
-impl From<SafeCell<Key>> for KeyCell {
-    fn from(value: SafeCell<Key>) -> Self {
-        Self(value)
-    }
-}
-impl TryFrom<SafeCell<Vec<u8>>> for KeyCell {
-    type Error = ();
-
-    fn try_from(mut value: SafeCell<Vec<u8>>) -> Result<Self, Self::Error> {
-        let value = value.read();
-        if value.len() != size_of::<Key>() {
-            return Err(());
-        }
-        let cell = SafeCell::new_inline(|cell_write: &mut Key| {
-            cell_write.copy_from_slice(&value);
-        });
-        Ok(Self(cell))
-    }
-}
-
-impl KeyCell {
-    pub fn new_secure_random() -> Self {
-        let key = SafeCell::new_inline(|key_buffer: &mut Key| {
-            let mut rng = StdRng::try_from_rng(&mut SysRng)
-                .expect("Rng failure is unrecoverable and should panic");
-            rng.fill_bytes(key_buffer);
-        });
-
-        key.into()
-    }
-
-    pub fn encrypt_in_place(
-        &mut self,
-        nonce: &Nonce,
-        associated_data: &[u8],
-        mut buffer: impl AsMut<Vec<u8>>,
-    ) -> Result<(), Error> {
-        let key_reader = self.0.read();
-        let cipher = XChaCha20Poly1305::new(&key_reader);
-        let nonce = XNonce::from_slice(nonce.0.as_ref());
-        let buffer = buffer.as_mut();
-        cipher.encrypt_in_place(nonce, associated_data, buffer)
-    }
-    pub fn decrypt_in_place(
-        &mut self,
-        nonce: &Nonce,
-        associated_data: &[u8],
-        buffer: &mut SafeCell<Vec<u8>>,
-    ) -> Result<(), Error> {
-        let key_reader = self.0.read();
-        let cipher = XChaCha20Poly1305::new(&key_reader);
-        let nonce = XNonce::from_slice(nonce.0.as_ref());
-        let mut buffer = buffer.write();
-        let buffer: &mut Vec<u8> = buffer.as_mut();
-        cipher.decrypt_in_place(nonce, associated_data, buffer)
-    }
-
-    pub fn encrypt(
-        &mut self,
-        nonce: &Nonce,
-        associated_data: &[u8],
-        plaintext: impl AsRef<[u8]>,
-    ) -> Result<Vec<u8>, Error> {
-        let key_reader = self.0.read();
-        let mut cipher = XChaCha20Poly1305::new(&key_reader);
-        let nonce = XNonce::from_slice(nonce.0.as_ref());
-
-        let ciphertext = cipher.encrypt(
-            nonce,
-            Payload {
-                msg: plaintext.as_ref(),
-                aad: associated_data,
-            },
-        )?;
-        Ok(ciphertext)
-    }
-}
-
-/// Derive a fixed-length key from the password using Argon2id, which is designed for password hashing and key derivation.
-pub fn derive_key(mut password: SafeCell<Vec<u8>>, salt: &Salt) -> KeyCell {
-    let params = {
-        #[cfg(debug_assertions)]
-        {
-            argon2::Params::new(8, 1, 1, None).unwrap()
-        }
-
-        #[cfg(not(debug_assertions))]
-        {
-            argon2::Params::new(262_144, 3, 4, None).unwrap()
-        }
-    };
-
-    let hasher = Argon2::new(Algorithm::Argon2id, argon2::Version::V0x13, params);
-    let mut key = SafeCell::new(Key::default());
-    password.read_inline(|password_source| {
-        let mut key_buffer = key.write();
-        let key_buffer: &mut [u8] = key_buffer.as_mut();
-
-        hasher
-            .hash_password_into(password_source, salt, key_buffer)
-            .expect("Better fail completely than return a weak key");
-    });
-
-    key.into()
-}
-
-#[cfg(test)]
-mod tests {
-    use super::{
-        derive_key,
-        encryption::v1::{Nonce, generate_salt},
-    };
-    use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-    #[test]
-    fn encrypt_decrypt() {
-        static PASSWORD: &[u8] = b"password";
-        let password = SafeCell::new(PASSWORD.to_vec());
-        let salt = generate_salt();
-
-        let mut key = derive_key(password, &salt);
-        let nonce = Nonce(*b"unique nonce 123 1231233"); // 24 bytes for XChaCha20Poly1305
-        let associated_data = b"associated data";
-        let mut buffer = b"secret data".to_vec();
-
-        key.encrypt_in_place(&nonce, associated_data, &mut buffer)
-            .unwrap();
-        assert_ne!(buffer, b"secret data");
-
-        let mut buffer = SafeCell::new(buffer);
-
-        key.decrypt_in_place(&nonce, associated_data, &mut buffer)
-            .unwrap();
-
-        let buffer = buffer.read();
-        assert_eq!(*buffer, b"secret data");
-    }
-}

server/crates/arbiter-server/src/db/mod.rs

@@ -5,6 +5,7 @@ use diesel_async::{
     sync_connection_wrapper::SyncConnectionWrapper,
 };
 use diesel_migrations::{EmbeddedMigrations, MigrationHarness, embed_migrations};
+use miette::Diagnostic;
 use thiserror::Error;
 use tracing::info;
 
@@ -20,31 +21,35 @@ static DB_FILE: &str = "arbiter.sqlite";
 
 const MIGRATIONS: EmbeddedMigrations = embed_migrations!("migrations");
 
-#[derive(Error, Debug)]
+#[derive(Error, Diagnostic, Debug)]
 pub enum DatabaseSetupError {
-    #[error(transparent)]
-    ConcurrencySetup(diesel::result::Error),
-
-    #[error(transparent)]
-    Connection(diesel::ConnectionError),
-
     #[error("Failed to determine home directory")]
+    #[diagnostic(code(arbiter::db::home_dir))]
     HomeDir(std::io::Error),
 
     #[error(transparent)]
+    #[diagnostic(code(arbiter::db::connection))]
+    Connection(diesel::ConnectionError),
+
+    #[error(transparent)]
+    #[diagnostic(code(arbiter::db::concurrency))]
+    ConcurrencySetup(diesel::result::Error),
+
+    #[error(transparent)]
+    #[diagnostic(code(arbiter::db::migration))]
     Migration(Box<dyn std::error::Error + Send + Sync>),
 
     #[error(transparent)]
+    #[diagnostic(code(arbiter::db::pool))]
     Pool(#[from] PoolInitError),
 }
 
 #[derive(Error, Debug)]
 pub enum DatabaseError {
-    #[error("Database query error")]
-    Connection(#[from] diesel::result::Error),
-
     #[error("Database connection error")]
     Pool(#[from] PoolError),
+    #[error("Database query error")]
+    Connection(#[from] diesel::result::Error),
 }
 
 #[tracing::instrument(level = "info")]
@@ -93,16 +98,13 @@ fn initialize_database(url: &str) -> Result<(), DatabaseSetupError> {
 }
 
 #[tracing::instrument(level = "info")]
-/// Creates a connection pool for the `SQLite` database.
-///
-/// # Panics
-/// Panics if the database path is not valid UTF-8.
 pub async fn create_pool(url: Option<&str>) -> Result<DatabasePool, DatabaseSetupError> {
     let database_url = url.map(String::from).unwrap_or(
+        #[allow(clippy::expect_used)]
         database_path()?
             .to_str()
             .expect("database path is not valid UTF-8")
-            .to_owned(),
+            .to_string(),
     );
 
     initialize_database(&database_url)?;
@@ -136,20 +138,19 @@ pub async fn create_pool(url: Option<&str>) -> Result<DatabasePool, DatabaseSetu
     Ok(pool)
 }
 
-#[mutants::skip]
-#[expect(clippy::missing_panics_doc, reason = "Tests oriented function")]
-/// Creates a test database pool with a temporary `SQLite` database file.
 pub async fn create_test_pool() -> DatabasePool {
     use rand::distr::{Alphanumeric, SampleString as _};
 
     let tempfile_name = Alphanumeric.sample_string(&mut rand::rng(), 16);
 
     let file = std::env::temp_dir().join(tempfile_name);
+    #[allow(clippy::expect_used)]
     let url = file
         .to_str()
         .expect("temp file path is not valid UTF-8")
-        .to_owned();
+        .to_string();
 
+    #[allow(clippy::expect_used)]
     create_pool(Some(&url))
         .await
         .expect("Failed to create test database pool")

server/crates/arbiter-server/src/db/models.rs

@@ -1,14 +1,13 @@
-#![allow(
+#![allow(unused)]
-    clippy::duplicated_attributes,
+#![allow(clippy::all)]
-    reason = "restructed's #[view] causes false positives"
+
-)]
 use crate::db::schema::{
     self, aead_encrypted, arbiter_settings, evm_basic_grant, evm_ether_transfer_grant,
     evm_ether_transfer_grant_target, evm_ether_transfer_limit, evm_token_transfer_grant,
     evm_token_transfer_log, evm_token_transfer_volume_limit, evm_transaction_log, evm_wallet,
-    integrity_envelope, root_key_history, tls_history,
+    root_key_history, tls_history,
 };
-
+use chrono::{DateTime, Utc};
 use diesel::{prelude::*, sqlite::Sqlite};
 use restructed::Models;
 
@@ -28,16 +27,16 @@ pub mod types {
     pub struct SqliteTimestamp(pub DateTime<Utc>);
     impl SqliteTimestamp {
         pub fn now() -> Self {
-            Self(Utc::now())
+            SqliteTimestamp(Utc::now())
         }
     }
 
-    impl From<DateTime<Utc>> for SqliteTimestamp {
+    impl From<chrono::DateTime<Utc>> for SqliteTimestamp {
-        fn from(dt: DateTime<Utc>) -> Self {
+        fn from(dt: chrono::DateTime<Utc>) -> Self {
-            Self(dt)
+            SqliteTimestamp(dt)
         }
     }
-    impl From<SqliteTimestamp> for DateTime<Utc> {
+    impl From<SqliteTimestamp> for chrono::DateTime<Utc> {
         fn from(ts: SqliteTimestamp) -> Self {
             ts.0
         }
@@ -48,11 +47,6 @@ pub mod types {
             &'b self,
             out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
         ) -> diesel::serialize::Result {
-            #[expect(
-                clippy::cast_possible_truncation,
-                clippy::as_conversions,
-                reason = "fixme! #84; this will break up in 2038 :3"
-            )]
             let unix_timestamp = self.0.timestamp() as i32;
             out.set_value(unix_timestamp);
             Ok(IsNull::No)
@@ -75,47 +69,41 @@ pub mod types {
             let datetime =
                 DateTime::from_timestamp(unix_timestamp, 0).ok_or("Timestamp is out of bounds")?;
 
-            Ok(Self(datetime))
+            Ok(SqliteTimestamp(datetime))
         }
     }
 
-    #[derive(Debug, FromSqlRow, AsExpression, Clone)]
+    /// Key algorithm stored in the `useragent_client.key_type` column.
+    /// Values must stay stable — they are persisted in the database.
+    #[derive(Debug, Clone, Copy, PartialEq, Eq, FromSqlRow, AsExpression, strum::FromRepr)]
     #[diesel(sql_type = Integer)]
-    #[repr(transparent)] // hint compiler to optimize the wrapper struct away
+    #[repr(i32)]
-    pub struct ChainId(pub i32);
+    pub enum KeyType {
-
+        Ed25519 = 1,
-    #[expect(
+        EcdsaSecp256k1 = 2,
-        clippy::cast_sign_loss,
+        Rsa = 3,
-        clippy::cast_possible_truncation,
-        clippy::as_conversions,
-        reason = "safe because chain_id is stored as i32 but is guaranteed to be a valid ChainId by the API when creating grants"
-    )]
-    const _: () = {
-        impl From<ChainId> for alloy::primitives::ChainId {
-            fn from(chain_id: ChainId) -> Self {
-                chain_id.0 as Self
-            }
-        }
-        impl From<alloy::primitives::ChainId> for ChainId {
-            fn from(chain_id: alloy::primitives::ChainId) -> Self {
-                Self(chain_id as _)
-            }
-        }
-    };
-
-    impl FromSql<Integer, Sqlite> for ChainId {
-        fn from_sql(
-            bytes: <Sqlite as diesel::backend::Backend>::RawValue<'_>,
-        ) -> diesel::deserialize::Result<Self> {
-            FromSql::<Integer, Sqlite>::from_sql(bytes).map(Self)
-        }
     }
-    impl ToSql<Integer, Sqlite> for ChainId {
+
+    impl ToSql<Integer, Sqlite> for KeyType {
         fn to_sql<'b>(
             &'b self,
             out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
         ) -> diesel::serialize::Result {
-            ToSql::<Integer, Sqlite>::to_sql(&self.0, out)
+            out.set_value(*self as i32);
+            Ok(IsNull::No)
+        }
+    }
+
+    impl FromSql<Integer, Sqlite> for KeyType {
+        fn from_sql(
+            mut bytes: <Sqlite as diesel::backend::Backend>::RawValue<'_>,
+        ) -> diesel::deserialize::Result<Self> {
+            let Some(SqliteType::Long) = bytes.value_type() else {
+                return Err("Expected Integer for KeyType".into());
+            };
+            let discriminant = bytes.read_long();
+            KeyType::from_repr(discriminant as i32)
+                .ok_or_else(|| format!("Unknown KeyType discriminant: {discriminant}").into())
         }
     }
 }
@@ -241,6 +229,7 @@ pub struct ProgramClientMetadataHistory {
 #[diesel(table_name = schema::program_client, check_for_backend(Sqlite))]
 pub struct ProgramClient {
     pub id: i32,
+    pub nonce: i32,
     pub public_key: Vec<u8>,
     pub metadata_id: i32,
     pub created_at: SqliteTimestamp,
@@ -248,12 +237,14 @@ pub struct ProgramClient {
 }
 
 #[derive(Queryable, Debug)]
-#[diesel(table_name = schema::operator_client, check_for_backend(Sqlite))]
+#[diesel(table_name = schema::useragent_client, check_for_backend(Sqlite))]
-pub struct OperatorClient {
+pub struct UseragentClient {
     pub id: i32,
+    pub nonce: i32,
     pub public_key: Vec<u8>,
     pub created_at: SqliteTimestamp,
     pub updated_at: SqliteTimestamp,
+    pub key_type: KeyType,
 }
 
 #[derive(Models, Queryable, Debug, Insertable, Selectable)]
@@ -281,7 +272,7 @@ pub struct EvmEtherTransferLimit {
 pub struct EvmBasicGrant {
     pub id: i32,
     pub wallet_access_id: i32, // references evm_wallet_access.id
-    pub chain_id: ChainId,
+    pub chain_id: i32,
     pub valid_from: Option<SqliteTimestamp>,
     pub valid_until: Option<SqliteTimestamp>,
     pub max_gas_fee_per_gas: Option<Vec<u8>>,
@@ -304,7 +295,7 @@ pub struct EvmTransactionLog {
     pub id: i32,
     pub grant_id: i32,
     pub wallet_access_id: i32,
-    pub chain_id: ChainId,
+    pub chain_id: i32,
     pub eth_value: Vec<u8>,
     pub signed_at: SqliteTimestamp,
 }
@@ -379,28 +370,9 @@ pub struct EvmTokenTransferLog {
     pub id: i32,
     pub grant_id: i32,
     pub log_id: i32,
-    pub chain_id: ChainId,
+    pub chain_id: i32,
     pub token_contract: Vec<u8>,
     pub recipient_address: Vec<u8>,
     pub value: Vec<u8>,
     pub created_at: SqliteTimestamp,
 }
-
-#[derive(Models, Queryable, Debug, Insertable, Selectable)]
-#[diesel(table_name = integrity_envelope, check_for_backend(Sqlite))]
-#[view(
-    NewIntegrityEnvelope,
-    derive(Insertable),
-    omit(id, signed_at, created_at),
-    attributes_with = "deriveless"
-)]
-pub struct IntegrityEnvelope {
-    pub id: i32,
-    pub entity_kind: String,
-    pub entity_id: Vec<u8>,
-    pub payload_version: i32,
-    pub key_version: i32,
-    pub mac: Vec<u8>,
-    pub signed_at: SqliteTimestamp,
-    pub created_at: SqliteTimestamp,
-}

server/crates/arbiter-server/src/db/schema.rs

@@ -139,22 +139,10 @@ diesel::table! {
     }
 }
 
-diesel::table! {
-    integrity_envelope (id) {
-        id -> Integer,
-        entity_kind -> Text,
-        entity_id -> Binary,
-        payload_version -> Integer,
-        key_version -> Integer,
-        mac -> Binary,
-        signed_at -> Integer,
-        created_at -> Integer,
-    }
-}
-
 diesel::table! {
     program_client (id) {
         id -> Integer,
+        nonce -> Integer,
         public_key -> Binary,
         metadata_id -> Integer,
         created_at -> Integer,
@@ -186,9 +174,11 @@ diesel::table! {
 }
 
 diesel::table! {
-    operator_client (id) {
+    useragent_client (id) {
         id -> Integer,
+        nonce -> Integer,
         public_key -> Binary,
+        key_type -> Integer,
         created_at -> Integer,
         updated_at -> Integer,
     }
@@ -229,9 +219,8 @@ diesel::allow_tables_to_appear_in_same_query!(
     evm_transaction_log,
     evm_wallet,
     evm_wallet_access,
-    integrity_envelope,
     program_client,
     root_key_history,
     tls_history,
-    operator_client,
+    useragent_client,
 );

server/crates/arbiter-server/src/evm/abi.rs

@@ -45,7 +45,7 @@ sol! {
 
 sol! {
     /// Permit2 — Uniswap's canonical token approval manager.
-    /// Replaces per-contract ERC-20 `approve()` with a single approval hub.
+    /// Replaces per-contract ERC-20 approve() with a single approval hub.
     #[derive(Debug)]
     interface IPermit2 {
         struct TokenPermissions {

server/crates/arbiter-server/src/evm/mod.rs

@@ -1,19 +1,5 @@
-use crate::{
+pub mod abi;
-    actors::vault::Vault,
+pub mod safe_signer;
-    crypto::integrity,
-    db::{
-        self, DatabaseError,
-        models::{
-            EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, NewEvmTransactionLog, SqliteTimestamp,
-        },
-        schema::{self, evm_transaction_log},
-    },
-    evm::policies::{
-        CombinedSettings, DatabaseID, EvalContext, EvalViolation, Grant, Policy,
-        SharedGrantSettings, SpecificGrant, SpecificMeaning, ether_transfer::EtherTransfer,
-        token_transfers::TokenTransfer,
-    },
-};
 
 use alloy::{
     consensus::TxEip1559,
@@ -22,56 +8,63 @@ use alloy::{
 use chrono::Utc;
 use diesel::{ExpressionMethods as _, QueryDsl as _, QueryResult, insert_into, sqlite::Sqlite};
 use diesel_async::{AsyncConnection, RunQueryDsl};
-use kameo::actor::ActorRef;
+use tracing_subscriber::registry::Data;
 
-pub mod abi;
+use crate::{
-pub mod safe_signer;
+    db::{
+        self, DatabaseError,
+        models::{
+            EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, NewEvmTransactionLog, SqliteTimestamp,
+        },
+        schema::{self, evm_transaction_log},
+    },
+    evm::policies::{
+        DatabaseID, EvalContext, EvalViolation, FullGrant, Grant, Policy, SharedGrantSettings,
+        SpecificGrant, SpecificMeaning, ether_transfer::EtherTransfer,
+        token_transfers::TokenTransfer,
+    },
+};
 
 pub mod policies;
 mod utils;
 
 /// Errors that can only occur once the transaction meaning is known (during policy evaluation)
-#[derive(Debug, thiserror::Error)]
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
 pub enum PolicyError {
     #[error("Database error")]
-    Database(#[from] DatabaseError),
+    Error(#[from] crate::db::DatabaseError),
     #[error("Transaction violates policy: {0:?}")]
+    #[diagnostic(code(arbiter_server::evm::policy_error::violation))]
     Violations(Vec<EvalViolation>),
     #[error("No matching grant found")]
+    #[diagnostic(code(arbiter_server::evm::policy_error::no_matching_grant))]
     NoMatchingGrant,
-
-    #[error("Integrity error: {0}")]
-    Integrity(#[from] integrity::Error),
 }
 
-#[derive(Debug, thiserror::Error)]
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
 pub enum VetError {
     #[error("Contract creation transactions are not supported")]
+    #[diagnostic(code(arbiter_server::evm::vet_error::contract_creation_unsupported))]
     ContractCreationNotSupported,
     #[error("Engine can't classify this transaction")]
+    #[diagnostic(code(arbiter_server::evm::vet_error::unsupported))]
     UnsupportedTransactionType,
     #[error("Policy evaluation failed: {1}")]
+    #[diagnostic(code(arbiter_server::evm::vet_error::evaluated))]
     Evaluated(SpecificMeaning, #[source] PolicyError),
 }
 
-#[derive(Debug, thiserror::Error)]
+#[derive(Debug, thiserror::Error, miette::Diagnostic)]
 pub enum AnalyzeError {
     #[error("Engine doesn't support granting permissions for contract creation")]
+    #[diagnostic(code(arbiter_server::evm::analyze_error::contract_creation_not_supported))]
     ContractCreationNotSupported,
 
     #[error("Unsupported transaction type")]
+    #[diagnostic(code(arbiter_server::evm::analyze_error::unsupported_transaction_type))]
     UnsupportedTransactionType,
 }
 
-#[derive(Debug, thiserror::Error)]
-pub enum ListError {
-    #[error("Database error")]
-    Database(#[from] DatabaseError),
-
-    #[error("Integrity verification failed for grant")]
-    Integrity(#[from] integrity::Error),
-}
-
 /// Controls whether a transaction should be executed or only validated
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum RunKind {
@@ -90,14 +83,6 @@ async fn check_shared_constraints(
     let mut violations = Vec::new();
     let now = Utc::now();
 
-    if shared.chain != context.chain {
-        violations.push(EvalViolation::MismatchingChainId {
-            expected: shared.chain,
-            actual: context.chain,
-        });
-        return Ok(violations);
-    }
-
     // Validity window
     if shared.valid_from.is_some_and(|t| now < t) || shared.valid_until.is_some_and(|t| now > t) {
         violations.push(EvalViolation::InvalidTime);
@@ -127,7 +112,7 @@ async fn check_shared_constraints(
             .get_result(conn)
             .await?;
 
-        if count >= rate_limit.count.into() {
+        if count >= rate_limit.count as i64 {
             violations.push(EvalViolation::RateLimitExceeded);
         }
     }
@@ -138,7 +123,6 @@ async fn check_shared_constraints(
 // Supporting only EIP-1559 transactions for now, but we can easily extend this to support legacy transactions if needed
 pub struct Engine {
     db: db::DatabasePool,
-    vault: ActorRef<Vault>,
 }
 
 impl Engine {
@@ -147,10 +131,7 @@ impl Engine {
         context: EvalContext,
         meaning: &P::Meaning,
         run_kind: RunKind,
-    ) -> Result<(), PolicyError>
+    ) -> Result<(), PolicyError> {
-    where
-        P::Settings: Clone,
-    {
         let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
 
         let grant = P::try_find_grant(&context, &mut conn)
@@ -158,16 +139,10 @@ impl Engine {
             .map_err(DatabaseError::from)?
             .ok_or(PolicyError::NoMatchingGrant)?;
 
-        integrity::verify_entity(&mut conn, &self.vault, &grant.settings, grant.id).await?;
+        let mut violations =
-
+            check_shared_constraints(&context, &grant.shared, grant.shared_grant_id, &mut conn)
-        let mut violations = check_shared_constraints(
+                .await
-            &context,
+                .map_err(DatabaseError::from)?;
-            &grant.settings.shared,
-            grant.common_settings_id,
-            &mut conn,
-        )
-        .await
-        .map_err(DatabaseError::from)?;
         violations.extend(
             P::evaluate(&context, meaning, &grant, &mut conn)
                 .await
@@ -176,16 +151,14 @@ impl Engine {
 
         if !violations.is_empty() {
             return Err(PolicyError::Violations(violations));
-        }
+        } else if run_kind == RunKind::Execution {
-
-        if run_kind == RunKind::Execution {
             conn.transaction(|conn| {
                 Box::pin(async move {
                     let log_id: i32 = insert_into(evm_transaction_log::table)
                         .values(&NewEvmTransactionLog {
-                            grant_id: grant.common_settings_id,
+                            grant_id: grant.shared_grant_id,
                             wallet_access_id: context.target.id,
-                            chain_id: context.chain.into(),
+                            chain_id: context.chain as i32,
                             eth_value: utils::u256_to_bytes(context.value).to_vec(),
                             signed_at: Utc::now().into(),
                         })
@@ -207,52 +180,42 @@ impl Engine {
 }
 
 impl Engine {
-    pub const fn new(db: db::DatabasePool, vault: ActorRef<Vault>) -> Self {
+    pub fn new(db: db::DatabasePool) -> Self {
-        Self { db, vault }
+        Self { db }
     }
 
     pub async fn create_grant<P: Policy>(
         &self,
-        full_grant: CombinedSettings<P::Settings>,
+        full_grant: FullGrant<P::Settings>,
-    ) -> Result<i32, DatabaseError>
+    ) -> Result<i32, DatabaseError> {
-    where
-        P::Settings: Clone,
-    {
         let mut conn = self.db.get().await?;
-        let vault = self.vault.clone();
 
         let id = conn
             .transaction(|conn| {
                 Box::pin(async move {
                     use schema::evm_basic_grant;
 
-                    #[expect(
-                        clippy::cast_possible_truncation,
-                        clippy::cast_possible_wrap,
-                        clippy::as_conversions,
-                        reason = "fixme! #86"
-                    )]
                     let basic_grant: EvmBasicGrant = insert_into(evm_basic_grant::table)
                         .values(&NewEvmBasicGrant {
-                            chain_id: full_grant.shared.chain.into(),
+                            chain_id: full_grant.basic.chain as i32,
-                            wallet_access_id: full_grant.shared.wallet_access_id,
+                            wallet_access_id: full_grant.basic.wallet_access_id,
-                            valid_from: full_grant.shared.valid_from.map(SqliteTimestamp),
+                            valid_from: full_grant.basic.valid_from.map(SqliteTimestamp),
-                            valid_until: full_grant.shared.valid_until.map(SqliteTimestamp),
+                            valid_until: full_grant.basic.valid_until.map(SqliteTimestamp),
                             max_gas_fee_per_gas: full_grant
-                                .shared
+                                .basic
                                 .max_gas_fee_per_gas
                                 .map(|fee| utils::u256_to_bytes(fee).to_vec()),
                             max_priority_fee_per_gas: full_grant
-                                .shared
+                                .basic
                                 .max_priority_fee_per_gas
                                 .map(|fee| utils::u256_to_bytes(fee).to_vec()),
                             rate_limit_count: full_grant
-                                .shared
+                                .basic
                                 .rate_limit
                                 .as_ref()
                                 .map(|rl| rl.count as i32),
                             rate_limit_window_secs: full_grant
-                                .shared
+                                .basic
                                 .rate_limit
                                 .as_ref()
                                 .map(|rl| rl.window.num_seconds() as i32),
@@ -262,13 +225,7 @@ impl Engine {
                         .get_result(conn)
                         .await?;
 
-                    P::create_grant(&basic_grant, &full_grant.specific, conn).await?;
+                    P::create_grant(&basic_grant, &full_grant.specific, conn).await
-
-                    integrity::sign_entity(conn, &vault, &full_grant, basic_grant.id)
-                        .await
-                        .map_err(|_| diesel::result::Error::RollbackTransaction)?;
-
-                    QueryResult::Ok(basic_grant.id)
                 })
             })
             .await?;
@@ -276,36 +233,33 @@ impl Engine {
         Ok(id)
     }
 
-    async fn list_one_kind<Kind: Policy, Y>(
+    pub async fn list_all_grants(&self) -> Result<Vec<Grant<SpecificGrant>>, DatabaseError> {
-        &self,
+        let mut conn = self.db.get().await?;
-        conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> Result<impl Iterator<Item = Grant<Y>>, ListError>
-    where
-        Y: From<Kind::Settings>,
-    {
-        let all_grants = Kind::find_all_grants(conn)
-            .await
-            .map_err(DatabaseError::from)?;
-
-        // Verify integrity of all grants before returning any results
-        for grant in &all_grants {
-            integrity::verify_entity(conn, &self.vault, &grant.settings, grant.id).await?;
-        }
-
-        Ok(all_grants.into_iter().map(|g| Grant {
-            id: g.id,
-            common_settings_id: g.common_settings_id,
-            settings: g.settings.generalize(),
-        }))
-    }
-
-    pub async fn list_all_grants(&self) -> Result<Vec<Grant<SpecificGrant>>, ListError> {
-        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
 
         let mut grants: Vec<Grant<SpecificGrant>> = Vec::new();
 
-        grants.extend(self.list_one_kind::<EtherTransfer, _>(&mut conn).await?);
+        grants.extend(
-        grants.extend(self.list_one_kind::<TokenTransfer, _>(&mut conn).await?);
+            EtherTransfer::find_all_grants(&mut conn)
+                .await?
+                .into_iter()
+                .map(|g| Grant {
+                    id: g.id,
+                    shared_grant_id: g.shared_grant_id,
+                    shared: g.shared,
+                    settings: SpecificGrant::EtherTransfer(g.settings),
+                }),
+        );
+        grants.extend(
+            TokenTransfer::find_all_grants(&mut conn)
+                .await?
+                .into_iter()
+                .map(|g| Grant {
+                    id: g.id,
+                    shared_grant_id: g.shared_grant_id,
+                    shared: g.shared,
+                    settings: SpecificGrant::TokenTransfer(g.settings),
+                }),
+        );
 
         Ok(grants)
     }
@@ -319,7 +273,7 @@ impl Engine {
         let TxKind::Call(to) = transaction.to else {
             return Err(VetError::ContractCreationNotSupported);
         };
-        let context = EvalContext {
+        let context = policies::EvalContext {
             target,
             chain: transaction.chain_id,
             to,
@@ -351,261 +305,3 @@ impl Engine {
         Err(VetError::UnsupportedTransactionType)
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use alloy::primitives::{Address, Bytes, U256, address};
-    use chrono::{Duration, Utc};
-    use diesel::{SelectableHelper, insert_into};
-    use diesel_async::RunQueryDsl;
-    use rstest::rstest;
-
-    use crate::db::{
-        self, DatabaseConnection,
-        models::{
-            EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, NewEvmTransactionLog, SqliteTimestamp,
-        },
-        schema::{evm_basic_grant, evm_transaction_log},
-    };
-    use crate::evm::policies::{
-        EvalContext, EvalViolation, SharedGrantSettings, TransactionRateLimit,
-    };
-
-    use super::check_shared_constraints;
-
-    const WALLET_ACCESS_ID: i32 = 1;
-    const CHAIN_ID: u64 = 1;
-    const RECIPIENT: Address = address!("1111111111111111111111111111111111111111");
-
-    fn context() -> EvalContext {
-        EvalContext {
-            target: EvmWalletAccess {
-                id: WALLET_ACCESS_ID,
-                wallet_id: 10,
-                client_id: 20,
-                created_at: SqliteTimestamp(Utc::now()),
-            },
-            chain: CHAIN_ID,
-            to: RECIPIENT,
-            value: U256::ZERO,
-            calldata: Bytes::new(),
-            max_fee_per_gas: 100,
-            max_priority_fee_per_gas: 10,
-        }
-    }
-
-    fn shared_settings() -> SharedGrantSettings {
-        SharedGrantSettings {
-            wallet_access_id: WALLET_ACCESS_ID,
-            chain: CHAIN_ID,
-            valid_from: None,
-            valid_until: None,
-            max_gas_fee_per_gas: None,
-            max_priority_fee_per_gas: None,
-            rate_limit: None,
-        }
-    }
-
-    async fn insert_basic_grant(
-        conn: &mut DatabaseConnection,
-        shared: &SharedGrantSettings,
-    ) -> EvmBasicGrant {
-        #[expect(
-            clippy::cast_possible_truncation,
-            clippy::cast_possible_wrap,
-            clippy::as_conversions,
-            reason = "fixme! #86"
-        )]
-        insert_into(evm_basic_grant::table)
-            .values(NewEvmBasicGrant {
-                wallet_access_id: shared.wallet_access_id,
-                chain_id: shared.chain.into(),
-                valid_from: shared.valid_from.map(SqliteTimestamp),
-                valid_until: shared.valid_until.map(SqliteTimestamp),
-                max_gas_fee_per_gas: shared
-                    .max_gas_fee_per_gas
-                    .map(|fee| super::utils::u256_to_bytes(fee).to_vec()),
-                max_priority_fee_per_gas: shared
-                    .max_priority_fee_per_gas
-                    .map(|fee| super::utils::u256_to_bytes(fee).to_vec()),
-                rate_limit_count: shared.rate_limit.as_ref().map(|limit| limit.count as i32),
-                rate_limit_window_secs: shared
-                    .rate_limit
-                    .as_ref()
-                    .map(|limit| limit.window.num_seconds() as i32),
-                revoked_at: None,
-            })
-            .returning(EvmBasicGrant::as_select())
-            .get_result(conn)
-            .await
-            .unwrap()
-    }
-
-    #[rstest]
-    #[case::matching_chain(CHAIN_ID, false)]
-    #[case::mismatching_chain(CHAIN_ID + 1, true)]
-    #[tokio::test]
-    async fn check_shared_constraints_enforces_chain_id(
-        #[case] context_chain: u64,
-        #[case] expect_mismatch: bool,
-    ) {
-        let db = db::create_test_pool().await;
-        let mut conn = db.get().await.unwrap();
-
-        let context = EvalContext {
-            chain: context_chain,
-            ..context()
-        };
-
-        let violations = check_shared_constraints(&context, &shared_settings(), 999, &mut *conn)
-            .await
-            .unwrap();
-
-        assert_eq!(
-            violations
-                .iter()
-                .any(|violation| matches!(violation, EvalViolation::MismatchingChainId { .. })),
-            expect_mismatch
-        );
-
-        if expect_mismatch {
-            assert_eq!(violations.len(), 1);
-        } else {
-            assert!(violations.is_empty());
-        }
-    }
-
-    #[rstest]
-    #[case::valid_from_in_bounds(Some(Utc::now() - Duration::hours(1)), None, false)]
-    #[case::valid_from_out_of_bounds(Some(Utc::now() + Duration::hours(1)), None, true)]
-    #[case::valid_until_in_bounds(None, Some(Utc::now() + Duration::hours(1)), false)]
-    #[case::valid_until_out_of_bounds(None, Some(Utc::now() - Duration::hours(1)), true)]
-    #[tokio::test]
-    async fn check_shared_constraints_enforces_validity_window(
-        #[case] valid_from: Option<chrono::DateTime<Utc>>,
-        #[case] valid_until: Option<chrono::DateTime<Utc>>,
-        #[case] expect_invalid_time: bool,
-    ) {
-        let db = db::create_test_pool().await;
-        let mut conn = db.get().await.unwrap();
-
-        let shared = SharedGrantSettings {
-            valid_from,
-            valid_until,
-            ..shared_settings()
-        };
-
-        let violations = check_shared_constraints(&context(), &shared, 999, &mut *conn)
-            .await
-            .unwrap();
-
-        assert_eq!(
-            violations
-                .iter()
-                .any(|violation| matches!(violation, EvalViolation::InvalidTime)),
-            expect_invalid_time
-        );
-
-        if expect_invalid_time {
-            assert_eq!(violations.len(), 1);
-        } else {
-            assert!(violations.is_empty());
-        }
-    }
-
-    #[rstest]
-    #[case::max_fee_within_limit(Some(U256::from(100u64)), None, 100, 10, false)]
-    #[case::max_fee_exceeded(Some(U256::from(99u64)), None, 100, 10, true)]
-    #[case::priority_fee_within_limit(None, Some(U256::from(10u64)), 100, 10, false)]
-    #[case::priority_fee_exceeded(None, Some(U256::from(9u64)), 100, 10, true)]
-    #[tokio::test]
-    async fn check_shared_constraints_enforces_gas_fee_caps(
-        #[case] max_gas_fee_per_gas: Option<U256>,
-        #[case] max_priority_fee_per_gas: Option<U256>,
-        #[case] actual_max_fee_per_gas: u128,
-        #[case] actual_max_priority_fee_per_gas: u128,
-        #[case] expect_gas_limit_violation: bool,
-    ) {
-        let db = db::create_test_pool().await;
-        let mut conn = db.get().await.unwrap();
-
-        let context = EvalContext {
-            max_fee_per_gas: actual_max_fee_per_gas,
-            max_priority_fee_per_gas: actual_max_priority_fee_per_gas,
-            ..context()
-        };
-
-        let shared = SharedGrantSettings {
-            max_gas_fee_per_gas,
-            max_priority_fee_per_gas,
-            ..shared_settings()
-        };
-        let violations = check_shared_constraints(&context, &shared, 999, &mut *conn)
-            .await
-            .unwrap();
-
-        assert_eq!(
-            violations
-                .iter()
-                .any(|violation| matches!(violation, EvalViolation::GasLimitExceeded { .. })),
-            expect_gas_limit_violation
-        );
-
-        if expect_gas_limit_violation {
-            assert_eq!(violations.len(), 1);
-        } else {
-            assert!(violations.is_empty());
-        }
-    }
-
-    #[rstest]
-    #[case::under_rate_limit(2, false)]
-    #[case::at_rate_limit(1, true)]
-    #[tokio::test]
-    async fn check_shared_constraints_enforces_rate_limit(
-        #[case] rate_limit_count: u32,
-        #[case] expect_rate_limit_violation: bool,
-    ) {
-        let db = db::create_test_pool().await;
-        let mut conn = db.get().await.unwrap();
-
-        let shared = SharedGrantSettings {
-            rate_limit: Some(TransactionRateLimit {
-                count: rate_limit_count,
-                window: Duration::hours(1),
-            }),
-            ..shared_settings()
-        };
-
-        let basic_grant = insert_basic_grant(&mut conn, &shared).await;
-
-        insert_into(evm_transaction_log::table)
-            .values(NewEvmTransactionLog {
-                grant_id: basic_grant.id,
-                wallet_access_id: WALLET_ACCESS_ID,
-                chain_id: CHAIN_ID.into(),
-                eth_value: super::utils::u256_to_bytes(U256::ZERO).to_vec(),
-                signed_at: SqliteTimestamp(Utc::now()),
-            })
-            .execute(&mut *conn)
-            .await
-            .unwrap();
-
-        let violations = check_shared_constraints(&context(), &shared, basic_grant.id, &mut *conn)
-            .await
-            .unwrap();
-
-        assert_eq!(
-            violations
-                .iter()
-                .any(|violation| matches!(violation, EvalViolation::RateLimitExceeded)),
-            expect_rate_limit_violation
-        );
-
-        if expect_rate_limit_violation {
-            assert_eq!(violations.len(), 1);
-        } else {
-            assert!(violations.is_empty());
-        }
-    }
-}

server/crates/arbiter-server/src/evm/policies.rs

@@ -1,8 +1,4 @@
-use crate::{
+use std::fmt::Display;
-    crypto::integrity::v1::Integrable,
-    db::models::{EvmBasicGrant, EvmWalletAccess},
-    evm::utils,
-};
 
 use alloy::primitives::{Address, Bytes, ChainId, U256};
 use chrono::{DateTime, Duration, Utc};
@@ -10,9 +6,14 @@ use diesel::{
     ExpressionMethods as _, QueryDsl, SelectableHelper, result::QueryResult, sqlite::Sqlite,
 };
 use diesel_async::{AsyncConnection, RunQueryDsl};
-use std::fmt::Display;
+use miette::Diagnostic;
 use thiserror::Error;
 
+use crate::{
+    db::models::{self, EvmBasicGrant, EvmWalletAccess},
+    evm::utils,
+};
+
 pub mod ether_transfer;
 pub mod token_transfers;
 
@@ -32,31 +33,34 @@ pub struct EvalContext {
     pub max_priority_fee_per_gas: u128,
 }
 
-#[derive(Debug, Error)]
+#[derive(Debug, Error, Diagnostic)]
 pub enum EvalViolation {
     #[error("This grant doesn't allow transactions to the target address {target}")]
+    #[diagnostic(code(arbiter_server::evm::eval_violation::invalid_target))]
     InvalidTarget { target: Address },
 
     #[error("Gas limit exceeded for this grant")]
+    #[diagnostic(code(arbiter_server::evm::eval_violation::gas_limit_exceeded))]
     GasLimitExceeded {
         max_gas_fee_per_gas: Option<U256>,
         max_priority_fee_per_gas: Option<U256>,
     },
 
     #[error("Rate limit exceeded for this grant")]
+    #[diagnostic(code(arbiter_server::evm::eval_violation::rate_limit_exceeded))]
     RateLimitExceeded,
 
     #[error("Transaction exceeds volumetric limits of the grant")]
+    #[diagnostic(code(arbiter_server::evm::eval_violation::volumetric_limit_exceeded))]
     VolumetricLimitExceeded,
 
     #[error("Transaction is outside of the grant's validity period")]
+    #[diagnostic(code(arbiter_server::evm::eval_violation::invalid_time))]
     InvalidTime,
 
     #[error("Transaction type is not allowed by this grant")]
+    #[diagnostic(code(arbiter_server::evm::eval_violation::invalid_transaction_type))]
     InvalidTransactionType,
-
-    #[error("Mismatching chain ID")]
-    MismatchingChainId { expected: ChainId, actual: ChainId },
 }
 
 pub type DatabaseID = i32;
@@ -64,12 +68,13 @@ pub type DatabaseID = i32;
 #[derive(Debug)]
 pub struct Grant<PolicySettings> {
     pub id: DatabaseID,
-    pub common_settings_id: DatabaseID, // ID of the basic grant for shared-logic checks like rate limits and validity periods
+    pub shared_grant_id: DatabaseID, // ID of the basic grant for shared-logic checks like rate limits and validity periods
-    pub settings: CombinedSettings<PolicySettings>,
+    pub shared: SharedGrantSettings,
+    pub settings: PolicySettings,
 }
 
 pub trait Policy: Sized {
-    type Settings: Send + Sync + 'static + Into<SpecificGrant> + Integrable;
+    type Settings: Send + Sync + 'static + Into<SpecificGrant>;
     type Meaning: Display + std::fmt::Debug + Send + Sync + 'static + Into<SpecificMeaning>;
 
     fn analyze(context: &EvalContext) -> Option<Self::Meaning>;
@@ -85,10 +90,10 @@ pub trait Policy: Sized {
 
     // Create a new grant in the database based on the provided grant details, and return its ID
     fn create_grant(
-        basic: &EvmBasicGrant,
+        basic: &models::EvmBasicGrant,
         grant: &Self::Settings,
         conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> impl Future<Output = QueryResult<DatabaseID>> + Send;
+    ) -> impl std::future::Future<Output = QueryResult<DatabaseID>> + Send;
 
     // Try to find an existing grant that matches the transaction context, and return its details if found
     // Additionally, return ID of basic grant for shared-logic checks like rate limits and validity periods
@@ -125,19 +130,19 @@ pub enum SpecificMeaning {
     TokenTransfer(token_transfers::Meaning),
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Hash, PartialOrd, Ord, arbiter_macros::Hashable)]
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub struct TransactionRateLimit {
     pub count: u32,
     pub window: Duration,
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Hash, PartialOrd, Ord, arbiter_macros::Hashable)]
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub struct VolumeRateLimit {
     pub max_volume: U256,
     pub window: Duration,
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Hash, arbiter_macros::Hashable)]
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub struct SharedGrantSettings {
     pub wallet_access_id: i32,
     pub chain: ChainId,
@@ -152,10 +157,10 @@ pub struct SharedGrantSettings {
 }
 
 impl SharedGrantSettings {
-    pub(crate) fn try_from_model(model: EvmBasicGrant) -> QueryResult<Self> {
+    fn try_from_model(model: EvmBasicGrant) -> QueryResult<Self> {
         Ok(Self {
             wallet_access_id: model.wallet_access_id,
-            chain: model.chain_id.into(),
+            chain: model.chain_id as u64, // safe because chain_id is stored as i32 but is guaranteed to be a valid ChainId by the API when creating grants
             valid_from: model.valid_from.map(Into::into),
             valid_until: model.valid_until.map(Into::into),
             max_gas_fee_per_gas: model
@@ -166,11 +171,10 @@ impl SharedGrantSettings {
                 .max_priority_fee_per_gas
                 .map(|b| utils::try_bytes_to_u256(&b))
                 .transpose()?,
-            #[expect(clippy::cast_sign_loss, clippy::as_conversions, reason = "fixme! #86")]
             rate_limit: match (model.rate_limit_count, model.rate_limit_window_secs) {
                 (Some(count), Some(window_secs)) => Some(TransactionRateLimit {
                     count: count as u32,
-                    window: Duration::seconds(window_secs.into()),
+                    window: Duration::seconds(window_secs as i64),
                 }),
                 _ => None,
             },
@@ -180,7 +184,7 @@ impl SharedGrantSettings {
     pub async fn query_by_id(
         conn: &mut impl AsyncConnection<Backend = Sqlite>,
         id: i32,
-    ) -> QueryResult<Self> {
+    ) -> diesel::result::QueryResult<Self> {
         use crate::db::schema::evm_basic_grant;
 
         let basic_grant: EvmBasicGrant = evm_basic_grant::table
@@ -199,22 +203,7 @@ pub enum SpecificGrant {
     TokenTransfer(token_transfers::Settings),
 }
 
-#[derive(Debug, arbiter_macros::Hashable)]
+pub struct FullGrant<PolicyGrant> {
-pub struct CombinedSettings<PolicyGrant> {
+    pub basic: SharedGrantSettings,
-    pub shared: SharedGrantSettings,
     pub specific: PolicyGrant,
 }
-
-impl<P> CombinedSettings<P> {
-    pub fn generalize<Y: From<P>>(self) -> CombinedSettings<Y> {
-        CombinedSettings {
-            shared: self.shared,
-            specific: self.specific.into(),
-        }
-    }
-}
-
-impl<P: Integrable> Integrable for CombinedSettings<P> {
-    const KIND: &'static str = P::KIND;
-    const VERSION: i32 = P::VERSION;
-}

server/crates/arbiter-server/src/evm/policies/ether_transfer/mod.rs

@@ -1,31 +1,28 @@
-use super::{DatabaseID, EvalContext, EvalViolation};
+use std::collections::HashMap;
-use crate::{
+use std::fmt::Display;
-    crypto::integrity::v1::Integrable,
-    db::models::{
-        EvmBasicGrant, EvmEtherTransferGrant, EvmEtherTransferGrantTarget, EvmEtherTransferLimit,
-        NewEvmEtherTransferLimit, SqliteTimestamp,
-    },
-    db::schema::{evm_basic_grant, evm_ether_transfer_limit, evm_transaction_log},
-    db::{
-        models::{NewEvmEtherTransferGrant, NewEvmEtherTransferGrantTarget},
-        schema::{evm_ether_transfer_grant, evm_ether_transfer_grant_target},
-    },
-    evm::policies::{
-        CombinedSettings, Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning,
-        VolumeRateLimit,
-    },
-    evm::{policies::Policy, utils},
-};
 
 use alloy::primitives::{Address, U256};
 use chrono::{DateTime, Duration, Utc};
-use diesel::{
+use diesel::dsl::{auto_type, insert_into};
-    dsl::{auto_type, insert_into},
+use diesel::sqlite::Sqlite;
-    prelude::*,
+use diesel::{ExpressionMethods, JoinOnDsl, prelude::*};
-    sqlite::Sqlite,
-};
 use diesel_async::{AsyncConnection, RunQueryDsl};
-use std::{collections::HashMap, fmt::Display};
+
+use crate::db::models::{
+    EvmBasicGrant, EvmEtherTransferGrant, EvmEtherTransferGrantTarget, EvmEtherTransferLimit,
+    NewEvmEtherTransferLimit, SqliteTimestamp,
+};
+use crate::db::schema::{evm_basic_grant, evm_ether_transfer_limit, evm_transaction_log};
+use crate::evm::policies::{
+    Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning, VolumeRateLimit,
+};
+use crate::{
+    db::{
+        models::{self, NewEvmEtherTransferGrant, NewEvmEtherTransferGrantTarget},
+        schema::{evm_ether_transfer_grant, evm_ether_transfer_grant_target},
+    },
+    evm::{policies::Policy, utils},
+};
 
 #[auto_type]
 fn grant_join() -> _ {
@@ -34,11 +31,13 @@ fn grant_join() -> _ {
     )
 }
 
+use super::{DatabaseID, EvalContext, EvalViolation};
+
 // Plain ether transfer
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub struct Meaning {
-    pub(crate) to: Address,
+    to: Address,
-    pub(crate) value: U256,
+    value: U256,
 }
 impl Display for Meaning {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
@@ -46,24 +45,21 @@ impl Display for Meaning {
     }
 }
 impl From<Meaning> for SpecificMeaning {
-    fn from(val: Meaning) -> Self {
+    fn from(val: Meaning) -> SpecificMeaning {
-        Self::EtherTransfer(val)
+        SpecificMeaning::EtherTransfer(val)
     }
 }
 
 // A grant for ether transfers, which can be scoped to specific target addresses and volume limits
-#[derive(Debug, Clone, arbiter_macros::Hashable)]
+#[derive(Debug, Clone)]
 pub struct Settings {
     pub target: Vec<Address>,
     pub limit: VolumeRateLimit,
 }
-impl Integrable for Settings {
-    const KIND: &'static str = "EtherTransfer";
-}
 
 impl From<Settings> for SpecificGrant {
-    fn from(val: Settings) -> Self {
+    fn from(val: Settings) -> SpecificGrant {
-        Self::EtherTransfer(val)
+        SpecificGrant::EtherTransfer(val)
     }
 }
 
@@ -74,7 +70,9 @@ async fn query_relevant_past_transaction(
 ) -> QueryResult<Vec<(U256, DateTime<Utc>)>> {
     let past_transactions: Vec<(Vec<u8>, SqliteTimestamp)> = evm_transaction_log::table
         .filter(evm_transaction_log::grant_id.eq(grant_id))
-        .filter(evm_transaction_log::signed_at.ge(SqliteTimestamp(Utc::now() - longest_window)))
+        .filter(
+            evm_transaction_log::signed_at.ge(SqliteTimestamp(chrono::Utc::now() - longest_window)),
+        )
         .select((
             evm_transaction_log::eth_value,
             evm_transaction_log::signed_at,
@@ -93,21 +91,20 @@ async fn query_relevant_past_transaction(
 
 async fn check_rate_limits(
     grant: &Grant<Settings>,
-    current_transfer_value: U256,
     db: &mut impl AsyncConnection<Backend = Sqlite>,
 ) -> QueryResult<Vec<EvalViolation>> {
     let mut violations = Vec::new();
-    let window = grant.settings.specific.limit.window;
+    let window = grant.settings.limit.window;
 
     let past_transaction = query_relevant_past_transaction(grant.id, window, db).await?;
 
-    let window_start = Utc::now() - grant.settings.specific.limit.window;
+    let window_start = chrono::Utc::now() - grant.settings.limit.window;
-    let prospective_cumulative_volume: U256 = past_transaction
+    let cumulative_volume: U256 = past_transaction
         .iter()
         .filter(|(_, timestamp)| timestamp >= &window_start)
-        .fold(current_transfer_value, |acc, (value, _)| acc + *value);
+        .fold(U256::default(), |acc, (value, _)| acc + *value);
 
-    if prospective_cumulative_volume > grant.settings.specific.limit.max_volume {
+    if cumulative_volume > grant.settings.limit.max_volume {
         violations.push(EvalViolation::VolumetricLimitExceeded);
     }
 
@@ -140,26 +137,21 @@ impl Policy for EtherTransfer {
         let mut violations = Vec::new();
 
         // Check if the target address is within the grant's allowed targets
-        if !grant.settings.specific.target.contains(&meaning.to) {
+        if !grant.settings.target.contains(&meaning.to) {
             violations.push(EvalViolation::InvalidTarget { target: meaning.to });
         }
 
-        let rate_violations = check_rate_limits(grant, meaning.value, db).await?;
+        let rate_violations = check_rate_limits(grant, db).await?;
         violations.extend(rate_violations);
 
         Ok(violations)
     }
 
     async fn create_grant(
-        basic: &EvmBasicGrant,
+        basic: &models::EvmBasicGrant,
         grant: &Self::Settings,
         conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> QueryResult<DatabaseID> {
+    ) -> diesel::result::QueryResult<DatabaseID> {
-        #[expect(
-            clippy::cast_possible_truncation,
-            clippy::as_conversions,
-            reason = "fixme! #86"
-        )]
         let limit_id: i32 = insert_into(evm_ether_transfer_limit::table)
             .values(NewEvmEtherTransferLimit {
                 window_secs: grant.limit.window.num_seconds() as i32,
@@ -194,7 +186,7 @@ impl Policy for EtherTransfer {
     async fn try_find_grant(
         context: &EvalContext,
         conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> QueryResult<Option<Grant<Self::Settings>>> {
+    ) -> diesel::result::QueryResult<Option<Grant<Self::Settings>>> {
         let target_bytes = context.to.to_vec();
 
         // Find a grant where:
@@ -248,17 +240,15 @@ impl Policy for EtherTransfer {
             limit: VolumeRateLimit {
                 max_volume: utils::try_bytes_to_u256(&limit.max_volume)
                     .map_err(|err| diesel::result::Error::DeserializationError(Box::new(err)))?,
-                window: Duration::seconds(limit.window_secs.into()),
+                window: chrono::Duration::seconds(limit.window_secs as i64),
             },
         };
 
         Ok(Some(Grant {
             id: grant.id,
-            common_settings_id: grant.basic_grant_id,
+            shared_grant_id: grant.basic_grant_id,
-            settings: CombinedSettings {
+            shared: SharedGrantSettings::try_from_model(basic_grant)?,
-                shared: SharedGrantSettings::try_from_model(basic_grant)?,
+            settings,
-                specific: settings,
-            },
         }))
     }
 
@@ -268,7 +258,7 @@ impl Policy for EtherTransfer {
         _log_id: i32,
         _grant: &Grant<Self::Settings>,
         _conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    ) -> QueryResult<()> {
+    ) -> diesel::result::QueryResult<()> {
         // Basic log is sufficient
 
         Ok(())
@@ -321,7 +311,7 @@ impl Policy for EtherTransfer {
             .map(|(basic, specific)| {
                 let targets: Vec<Address> = targets_by_grant
                     .get(&specific.id)
-                    .map(Vec::as_slice)
+                    .map(|v| v.as_slice())
                     .unwrap_or_default()
                     .iter()
                     .filter_map(|t| {
@@ -336,17 +326,15 @@ impl Policy for EtherTransfer {
 
                 Ok(Grant {
                     id: specific.id,
-                    common_settings_id: specific.basic_grant_id,
+                    shared_grant_id: specific.basic_grant_id,
-                    settings: CombinedSettings {
+                    shared: SharedGrantSettings::try_from_model(basic)?,
-                        shared: SharedGrantSettings::try_from_model(basic)?,
+                    settings: Settings {
-                        specific: Settings {
+                        target: targets,
-                            target: targets,
+                        limit: VolumeRateLimit {
-                            limit: VolumeRateLimit {
+                            max_volume: utils::try_bytes_to_u256(&limit.max_volume).map_err(
-                                max_volume: utils::try_bytes_to_u256(&limit.max_volume).map_err(
+                                |e| diesel::result::Error::DeserializationError(Box::new(e)),
-                                    |e| diesel::result::Error::DeserializationError(Box::new(e)),
+                            )?,
-                                )?,
+                            window: Duration::seconds(limit.window_secs as i64),
-                                window: Duration::seconds(limit.window_secs.into()),
-                            },
                         },
                     },
                 })

server/crates/arbiter-server/src/evm/policies/ether_transfer/tests.rs

@@ -1,28 +1,24 @@
-use super::{EtherTransfer, Settings};
-use crate::{
-    db::{
-        self, DatabaseConnection,
-        models::{
-            EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, NewEvmTransactionLog, SqliteTimestamp,
-        },
-        schema::{evm_basic_grant, evm_transaction_log},
-    },
-    evm::{
-        policies::{
-            CombinedSettings, EvalContext, EvalViolation, Grant, Policy, SharedGrantSettings,
-            VolumeRateLimit,
-        },
-        utils,
-    },
-};
-
 use alloy::primitives::{Address, Bytes, U256, address};
 use chrono::{Duration, Utc};
 use diesel::{SelectableHelper, insert_into};
 use diesel_async::RunQueryDsl;
 
+use crate::db::{
+    self, DatabaseConnection,
+    models::{
+        EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, NewEvmTransactionLog, SqliteTimestamp,
+    },
+    schema::{evm_basic_grant, evm_transaction_log},
+};
+use crate::evm::{
+    policies::{EvalContext, EvalViolation, Grant, Policy, SharedGrantSettings, VolumeRateLimit},
+    utils,
+};
+
+use super::{EtherTransfer, Settings};
+
 const WALLET_ACCESS_ID: i32 = 1;
-const CHAIN_ID: alloy::primitives::ChainId = 1;
+const CHAIN_ID: u64 = 1;
 
 const ALLOWED: Address = address!("1111111111111111111111111111111111111111");
 const OTHER: Address = address!("2222222222222222222222222222222222222222");
@@ -48,7 +44,7 @@ async fn insert_basic(conn: &mut DatabaseConnection, revoked: bool) -> EvmBasicG
     insert_into(evm_basic_grant::table)
         .values(NewEvmBasicGrant {
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             valid_from: None,
             valid_until: None,
             max_gas_fee_per_gas: None,
@@ -85,6 +81,8 @@ fn shared() -> SharedGrantSettings {
     }
 }
 
+// ── analyze ─────────────────────────────────────────────────────────────
+
 #[test]
 fn analyze_matches_empty_calldata() {
     let m = EtherTransfer::analyze(&ctx(ALLOWED, U256::from(1_000u64))).unwrap();
@@ -101,6 +99,8 @@ fn analyze_rejects_nonempty_calldata() {
     assert!(EtherTransfer::analyze(&context).is_none());
 }
 
+// ── evaluate ────────────────────────────────────────────────────────────
+
 #[tokio::test]
 async fn evaluate_passes_for_allowed_target() {
     let db = db::create_test_pool().await;
@@ -108,11 +108,9 @@ async fn evaluate_passes_for_allowed_target() {
 
     let grant = Grant {
         id: 999,
-        common_settings_id: 999,
+        shared_grant_id: 999,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings: make_settings(vec![ALLOWED], 1_000_000),
-            specific: make_settings(vec![ALLOWED], 1_000_000),
-        },
     };
     let context = ctx(ALLOWED, U256::from(100u64));
     let m = EtherTransfer::analyze(&context).unwrap();
@@ -129,11 +127,9 @@ async fn evaluate_rejects_disallowed_target() {
 
     let grant = Grant {
         id: 999,
-        common_settings_id: 999,
+        shared_grant_id: 999,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings: make_settings(vec![ALLOWED], 1_000_000),
-            specific: make_settings(vec![ALLOWED], 1_000_000),
-        },
     };
     let context = ctx(OTHER, U256::from(100u64));
     let m = EtherTransfer::analyze(&context).unwrap();
@@ -161,7 +157,7 @@ async fn evaluate_passes_when_volume_within_limit() {
         .values(NewEvmTransactionLog {
             grant_id,
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             eth_value: utils::u256_to_bytes(U256::from(500u64)).to_vec(),
             signed_at: SqliteTimestamp(Utc::now()),
         })
@@ -171,11 +167,9 @@ async fn evaluate_passes_when_volume_within_limit() {
 
     let grant = Grant {
         id: grant_id,
-        common_settings_id: basic.id,
+        shared_grant_id: basic.id,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings,
-            specific: settings,
-        },
     };
     let context = ctx(ALLOWED, U256::from(100u64));
     let m = EtherTransfer::analyze(&context).unwrap();
@@ -203,8 +197,8 @@ async fn evaluate_rejects_volume_over_limit() {
         .values(NewEvmTransactionLog {
             grant_id,
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
-            eth_value: utils::u256_to_bytes(U256::from(1_000u64)).to_vec(),
+            eth_value: utils::u256_to_bytes(U256::from(1_001u64)).to_vec(),
             signed_at: SqliteTimestamp(Utc::now()),
         })
         .execute(&mut *conn)
@@ -213,13 +207,11 @@ async fn evaluate_rejects_volume_over_limit() {
 
     let grant = Grant {
         id: grant_id,
-        common_settings_id: basic.id,
+        shared_grant_id: basic.id,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings,
-            specific: settings,
-        },
     };
-    let context = ctx(ALLOWED, U256::from(1u64));
+    let context = ctx(ALLOWED, U256::from(100u64));
     let m = EtherTransfer::analyze(&context).unwrap();
     let v = EtherTransfer::evaluate(&context, &m, &grant, &mut *conn)
         .await
@@ -241,13 +233,13 @@ async fn evaluate_passes_at_exactly_volume_limit() {
         .await
         .unwrap();
 
-    // Exactly at the limit including current transfer — check is `>`, so this should not violate
+    // Exactly at the limit — the check is `>`, so this should not violate
     insert_into(evm_transaction_log::table)
         .values(NewEvmTransactionLog {
             grant_id,
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
-            eth_value: utils::u256_to_bytes(U256::from(900u64)).to_vec(),
+            eth_value: utils::u256_to_bytes(U256::from(1_000u64)).to_vec(),
             signed_at: SqliteTimestamp(Utc::now()),
         })
         .execute(&mut *conn)
@@ -256,11 +248,9 @@ async fn evaluate_passes_at_exactly_volume_limit() {
 
     let grant = Grant {
         id: grant_id,
-        common_settings_id: basic.id,
+        shared_grant_id: basic.id,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings,
-            specific: settings,
-        },
     };
     let context = ctx(ALLOWED, U256::from(100u64));
     let m = EtherTransfer::analyze(&context).unwrap();
@@ -273,6 +263,8 @@ async fn evaluate_passes_at_exactly_volume_limit() {
     );
 }
 
+// ── try_find_grant ───────────────────────────────────────────────────────
+
 #[tokio::test]
 async fn try_find_grant_roundtrip() {
     let db = db::create_test_pool().await;
@@ -290,11 +282,8 @@ async fn try_find_grant_roundtrip() {
 
     assert!(found.is_some());
     let g = found.unwrap();
-    assert_eq!(g.settings.specific.target, vec![ALLOWED]);
+    assert_eq!(g.settings.target, vec![ALLOWED]);
-    assert_eq!(
+    assert_eq!(g.settings.limit.max_volume, U256::from(1_000_000u64));
-        g.settings.specific.limit.max_volume,
-        U256::from(1_000_000u64)
-    );
 }
 
 #[tokio::test]
@@ -331,36 +320,7 @@ async fn try_find_grant_wrong_target_returns_none() {
     assert!(found.is_none());
 }
 
-proptest::proptest! {
+// ── find_all_grants ──────────────────────────────────────────────────────
-    #[test]
-    fn target_order_does_not_affect_hash(
-        raw_addrs in proptest::collection::vec(proptest::prelude::any::<[u8; 20]>(), 0..8),
-        seed in proptest::prelude::any::<u64>(),
-        max_volume in proptest::prelude::any::<u64>(),
-        window_secs in 1i64..=86400,
-    ) {
-        use rand::{SeedableRng, seq::SliceRandom};
-        use sha2::Digest;
-        use arbiter_crypto::hashing::Hashable;
-
-        let addrs: Vec<Address> = raw_addrs.iter().map(|b| Address::from(*b)).collect();
-        let mut shuffled = addrs.clone();
-        shuffled.shuffle(&mut rand::rngs::StdRng::seed_from_u64(seed));
-
-        let limit = VolumeRateLimit {
-            max_volume: U256::from(max_volume),
-            window: Duration::seconds(window_secs),
-        };
-
-        let mut h1 = sha2::Sha256::new();
-        Settings { target: addrs, limit: limit.clone() }.hash(&mut h1);
-
-        let mut h2 = sha2::Sha256::new();
-        Settings { target: shuffled, limit }.hash(&mut h2);
-
-        proptest::prop_assert_eq!(h1.finalize(), h2.finalize());
-    }
-}
 
 #[tokio::test]
 async fn find_all_grants_empty_db() {
@@ -387,7 +347,7 @@ async fn find_all_grants_excludes_revoked() {
 
     let all = EtherTransfer::find_all_grants(&mut *conn).await.unwrap();
     assert_eq!(all.len(), 1);
-    assert_eq!(all[0].settings.specific.target, vec![ALLOWED]);
+    assert_eq!(all[0].settings.target, vec![ALLOWED]);
 }
 
 #[tokio::test]
@@ -403,11 +363,8 @@ async fn find_all_grants_multiple_targets() {
 
     let all = EtherTransfer::find_all_grants(&mut *conn).await.unwrap();
     assert_eq!(all.len(), 1);
-    assert_eq!(all[0].settings.specific.target.len(), 2);
+    assert_eq!(all[0].settings.target.len(), 2);
-    assert_eq!(
+    assert_eq!(all[0].settings.limit.max_volume, U256::from(1_000_000u64));
-        all[0].settings.specific.limit.max_volume,
-        U256::from(1_000_000u64)
-    );
 }
 
 #[tokio::test]

server/crates/arbiter-server/src/evm/policies/token_transfers/mod.rs

@@ -1,38 +1,33 @@
-use super::{DatabaseID, EvalContext, EvalViolation};
+use std::collections::HashMap;
-use crate::{
-    crypto::integrity::Integrable,
-    db::models::{
-        EvmBasicGrant, EvmTokenTransferGrant, EvmTokenTransferVolumeLimit,
-        NewEvmTokenTransferGrant, NewEvmTokenTransferLog, NewEvmTokenTransferVolumeLimit,
-        SqliteTimestamp,
-    },
-    db::schema::{
-        evm_basic_grant, evm_token_transfer_grant, evm_token_transfer_log,
-        evm_token_transfer_volume_limit,
-    },
-    evm::policies::CombinedSettings,
-    evm::{
-        abi::IERC20::transferCall,
-        policies::{
-            Grant, Policy, SharedGrantSettings, SpecificGrant, SpecificMeaning, VolumeRateLimit,
-        },
-        utils,
-    },
-};
-use arbiter_tokens_registry::evm::nonfungible::{self, TokenInfo};
 
 use alloy::{
     primitives::{Address, U256},
     sol_types::SolCall,
 };
+use arbiter_tokens_registry::evm::nonfungible::{self, TokenInfo};
 use chrono::{DateTime, Duration, Utc};
-use diesel::{
+use diesel::dsl::{auto_type, insert_into};
-    dsl::{auto_type, insert_into},
+use diesel::sqlite::Sqlite;
-    prelude::*,
+use diesel::{ExpressionMethods, prelude::*};
-    sqlite::Sqlite,
-};
 use diesel_async::{AsyncConnection, RunQueryDsl};
-use std::collections::HashMap;
+
+use crate::db::models::{
+    EvmBasicGrant, EvmTokenTransferGrant, EvmTokenTransferVolumeLimit, NewEvmTokenTransferGrant,
+    NewEvmTokenTransferLog, NewEvmTokenTransferVolumeLimit, SqliteTimestamp,
+};
+use crate::db::schema::{
+    evm_basic_grant, evm_token_transfer_grant, evm_token_transfer_log,
+    evm_token_transfer_volume_limit,
+};
+use crate::evm::{
+    abi::IERC20::transferCall,
+    policies::{
+        Grant, Policy, SharedGrantSettings, SpecificGrant, SpecificMeaning, VolumeRateLimit,
+    },
+    utils,
+};
+
+use super::{DatabaseID, EvalContext, EvalViolation};
 
 #[auto_type]
 fn grant_join() -> _ {
@@ -43,9 +38,9 @@ fn grant_join() -> _ {
 
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub struct Meaning {
-    pub token: &'static TokenInfo,
+    token: &'static TokenInfo,
-    pub to: Address,
+    to: Address,
-    pub value: U256,
+    value: U256,
 }
 impl std::fmt::Display for Meaning {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
@@ -57,25 +52,21 @@ impl std::fmt::Display for Meaning {
     }
 }
 impl From<Meaning> for SpecificMeaning {
-    fn from(val: Meaning) -> Self {
+    fn from(val: Meaning) -> SpecificMeaning {
-        Self::TokenTransfer(val)
+        SpecificMeaning::TokenTransfer(val)
     }
 }
 
 // A grant for token transfers, which can be scoped to specific target addresses and volume limits
-#[derive(Debug, Clone, arbiter_macros::Hashable)]
+#[derive(Debug, Clone)]
 pub struct Settings {
     pub token_contract: Address,
     pub target: Option<Address>,
     pub volume_limits: Vec<VolumeRateLimit>,
 }
-impl Integrable for Settings {
-    const KIND: &'static str = "TokenTransfer";
-}
-
 impl From<Settings> for SpecificGrant {
-    fn from(val: Settings) -> Self {
+    fn from(val: Settings) -> SpecificGrant {
-        Self::TokenTransfer(val)
+        SpecificGrant::TokenTransfer(val)
     }
 }
 
@@ -86,7 +77,10 @@ async fn query_relevant_past_transfers(
 ) -> QueryResult<Vec<(U256, DateTime<Utc>)>> {
     let past_logs: Vec<(Vec<u8>, SqliteTimestamp)> = evm_token_transfer_log::table
         .filter(evm_token_transfer_log::grant_id.eq(grant_id))
-        .filter(evm_token_transfer_log::created_at.ge(SqliteTimestamp(Utc::now() - longest_window)))
+        .filter(
+            evm_token_transfer_log::created_at
+                .ge(SqliteTimestamp(chrono::Utc::now() - longest_window)),
+        )
         .select((
             evm_token_transfer_log::value,
             evm_token_transfer_log::created_at,
@@ -107,32 +101,24 @@ async fn query_relevant_past_transfers(
 
 async fn check_volume_rate_limits(
     grant: &Grant<Settings>,
-    current_transfer_value: U256,
     db: &mut impl AsyncConnection<Backend = Sqlite>,
 ) -> QueryResult<Vec<EvalViolation>> {
     let mut violations = Vec::new();
 
-    let Some(longest_window) = grant
+    let Some(longest_window) = grant.settings.volume_limits.iter().map(|l| l.window).max() else {
-        .settings
-        .specific
-        .volume_limits
-        .iter()
-        .map(|l| l.window)
-        .max()
-    else {
         return Ok(violations);
     };
 
     let past_transfers = query_relevant_past_transfers(grant.id, longest_window, db).await?;
 
-    for limit in &grant.settings.specific.volume_limits {
+    for limit in &grant.settings.volume_limits {
-        let window_start = Utc::now() - limit.window;
+        let window_start = chrono::Utc::now() - limit.window;
-        let prospective_cumulative_volume: U256 = past_transfers
+        let cumulative_volume: U256 = past_transfers
             .iter()
             .filter(|(_, timestamp)| timestamp >= &window_start)
-            .fold(current_transfer_value, |acc, (value, _)| acc + *value);
+            .fold(U256::default(), |acc, (value, _)| acc + *value);
 
-        if prospective_cumulative_volume > limit.max_volume {
+        if cumulative_volume > limit.max_volume {
             violations.push(EvalViolation::VolumetricLimitExceeded);
             break;
         }
@@ -171,13 +157,13 @@ impl Policy for TokenTransfer {
             return Ok(violations);
         }
 
-        if let Some(allowed) = grant.settings.specific.target
+        if let Some(allowed) = grant.settings.target
             && allowed != meaning.to
         {
             violations.push(EvalViolation::InvalidTarget { target: meaning.to });
         }
 
-        let rate_violations = check_volume_rate_limits(grant, meaning.value, db).await?;
+        let rate_violations = check_volume_rate_limits(grant, db).await?;
         violations.extend(rate_violations);
 
         Ok(violations)
@@ -202,11 +188,6 @@ impl Policy for TokenTransfer {
             .await?;
 
         for limit in &grant.volume_limits {
-            #[expect(
-                clippy::cast_possible_truncation,
-                clippy::as_conversions,
-                reason = "fixme! #86"
-            )]
             insert_into(evm_token_transfer_volume_limit::table)
                 .values(NewEvmTokenTransferVolumeLimit {
                     grant_id,
@@ -256,7 +237,7 @@ impl Policy for TokenTransfer {
                     max_volume: utils::try_bytes_to_u256(&row.max_volume).map_err(|err| {
                         diesel::result::Error::DeserializationError(Box::new(err))
                     })?,
-                    window: Duration::seconds(row.window_secs.into()),
+                    window: Duration::seconds(row.window_secs as i64),
                 })
             })
             .collect::<QueryResult<Vec<_>>>()?;
@@ -287,11 +268,9 @@ impl Policy for TokenTransfer {
 
         Ok(Some(Grant {
             id: token_grant.id,
-            common_settings_id: token_grant.basic_grant_id,
+            shared_grant_id: token_grant.basic_grant_id,
-            settings: CombinedSettings {
+            shared: SharedGrantSettings::try_from_model(basic_grant)?,
-                shared: SharedGrantSettings::try_from_model(basic_grant)?,
+            settings,
-                specific: settings,
-            },
         }))
     }
 
@@ -306,7 +285,7 @@ impl Policy for TokenTransfer {
             .values(NewEvmTokenTransferLog {
                 grant_id: grant.id,
                 log_id,
-                chain_id: context.chain.into(),
+                chain_id: context.chain as i32,
                 token_contract: context.to.to_vec(),
                 recipient_address: meaning.to.to_vec(),
                 value: utils::u256_to_bytes(meaning.value).to_vec(),
@@ -355,7 +334,7 @@ impl Policy for TokenTransfer {
             .map(|(basic, specific)| {
                 let volume_limits: Vec<VolumeRateLimit> = limits_by_grant
                     .get(&specific.id)
-                    .map(Vec::as_slice)
+                    .map(|v| v.as_slice())
                     .unwrap_or_default()
                     .iter()
                     .map(|row| {
@@ -363,7 +342,7 @@ impl Policy for TokenTransfer {
                             max_volume: utils::try_bytes_to_u256(&row.max_volume).map_err(|e| {
                                 diesel::result::Error::DeserializationError(Box::new(e))
                             })?,
-                            window: Duration::seconds(row.window_secs.into()),
+                            window: Duration::seconds(row.window_secs as i64),
                         })
                     })
                     .collect::<QueryResult<Vec<_>>>()?;
@@ -389,14 +368,12 @@ impl Policy for TokenTransfer {
 
                 Ok(Grant {
                     id: specific.id,
-                    common_settings_id: specific.basic_grant_id,
+                    shared_grant_id: specific.basic_grant_id,
-                    settings: CombinedSettings {
+                    shared: SharedGrantSettings::try_from_model(basic)?,
-                        shared: SharedGrantSettings::try_from_model(basic)?,
+                    settings: Settings {
-                        specific: Settings {
+                        token_contract: Address::from(token_contract),
-                            token_contract: Address::from(token_contract),
+                        target,
-                            target,
+                        volume_limits,
-                            volume_limits,
-                        },
                     },
                 })
             })

server/crates/arbiter-server/src/evm/policies/token_transfers/tests.rs

@@ -1,28 +1,22 @@
-use super::{Settings, TokenTransfer};
+use alloy::primitives::{Address, Bytes, U256, address};
-use crate::{
+use alloy::sol_types::SolCall;
-    db::{
-        self, DatabaseConnection,
-        models::{EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, SqliteTimestamp},
-        schema::evm_basic_grant,
-    },
-    evm::{
-        abi::IERC20::transferCall,
-        policies::{
-            CombinedSettings, EvalContext, EvalViolation, Grant, Policy, SharedGrantSettings,
-            VolumeRateLimit,
-        },
-        utils,
-    },
-};
-
-use alloy::{
-    primitives::{Address, Bytes, U256, address},
-    sol_types::SolCall,
-};
 use chrono::{Duration, Utc};
 use diesel::{SelectableHelper, insert_into};
 use diesel_async::RunQueryDsl;
 
+use crate::db::{
+    self, DatabaseConnection,
+    models::{EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, SqliteTimestamp},
+    schema::evm_basic_grant,
+};
+use crate::evm::{
+    abi::IERC20::transferCall,
+    policies::{EvalContext, EvalViolation, Grant, Policy, SharedGrantSettings, VolumeRateLimit},
+    utils,
+};
+
+use super::{Settings, TokenTransfer};
+
 // DAI on Ethereum mainnet — present in the static token registry
 const CHAIN_ID: u64 = 1;
 const DAI: Address = address!("6B175474E89094C44Da98b954EedeAC495271d0F");
@@ -62,7 +56,7 @@ async fn insert_basic(conn: &mut DatabaseConnection, revoked: bool) -> EvmBasicG
     insert_into(evm_basic_grant::table)
         .values(NewEvmBasicGrant {
             wallet_access_id: WALLET_ACCESS_ID,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             valid_from: None,
             valid_until: None,
             max_gas_fee_per_gas: None,
@@ -104,6 +98,8 @@ fn shared() -> SharedGrantSettings {
     }
 }
 
+// ── analyze ─────────────────────────────────────────────────────────────
+
 #[test]
 fn analyze_known_token_valid_calldata() {
     let calldata = transfer_calldata(RECIPIENT, U256::from(100u64));
@@ -129,6 +125,8 @@ fn analyze_empty_calldata_returns_none() {
     assert!(TokenTransfer::analyze(&ctx(DAI, Bytes::new())).is_none());
 }
 
+// ── evaluate ────────────────────────────────────────────────────────────
+
 #[tokio::test]
 async fn evaluate_rejects_nonzero_eth_value() {
     let db = db::create_test_pool().await;
@@ -136,11 +134,9 @@ async fn evaluate_rejects_nonzero_eth_value() {
 
     let grant = Grant {
         id: 999,
-        common_settings_id: 999,
+        shared_grant_id: 999,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings: make_settings(None, None),
-            specific: make_settings(None, None),
-        },
     };
     let calldata = transfer_calldata(RECIPIENT, U256::from(100u64));
     let mut context = ctx(DAI, calldata);
@@ -167,11 +163,9 @@ async fn evaluate_passes_any_recipient_when_no_restriction() {
 
     let grant = Grant {
         id: 999,
-        common_settings_id: 999,
+        shared_grant_id: 999,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings: make_settings(None, None),
-            specific: make_settings(None, None),
-        },
     };
     let calldata = transfer_calldata(RECIPIENT, U256::from(100u64));
     let context = ctx(DAI, calldata);
@@ -189,11 +183,9 @@ async fn evaluate_passes_matching_restricted_recipient() {
 
     let grant = Grant {
         id: 999,
-        common_settings_id: 999,
+        shared_grant_id: 999,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings: make_settings(Some(RECIPIENT), None),
-            specific: make_settings(Some(RECIPIENT), None),
-        },
     };
     let calldata = transfer_calldata(RECIPIENT, U256::from(100u64));
     let context = ctx(DAI, calldata);
@@ -211,11 +203,9 @@ async fn evaluate_rejects_wrong_restricted_recipient() {
 
     let grant = Grant {
         id: 999,
-        common_settings_id: 999,
+        shared_grant_id: 999,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings: make_settings(Some(RECIPIENT), None),
-            specific: make_settings(Some(RECIPIENT), None),
-        },
     };
     let calldata = transfer_calldata(OTHER, U256::from(100u64));
     let context = ctx(DAI, calldata);
@@ -230,7 +220,7 @@ async fn evaluate_rejects_wrong_restricted_recipient() {
 }
 
 #[tokio::test]
-async fn evaluate_passes_volume_at_exact_limit() {
+async fn evaluate_passes_volume_within_limit() {
     let db = db::create_test_pool().await;
     let mut conn = db.get().await.unwrap();
 
@@ -240,15 +230,16 @@ async fn evaluate_passes_volume_at_exact_limit() {
         .await
         .unwrap();
 
-    // Record a past transfer of 900, with current transfer 100 => exactly 1000 limit
+    // Record a past transfer of 500 (within 1000 limit)
-    insert_into(db::schema::evm_token_transfer_log::table)
+    use crate::db::{models::NewEvmTokenTransferLog, schema::evm_token_transfer_log};
-        .values(db::models::NewEvmTokenTransferLog {
+    insert_into(evm_token_transfer_log::table)
+        .values(NewEvmTokenTransferLog {
             grant_id,
             log_id: 0,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             token_contract: DAI.to_vec(),
             recipient_address: RECIPIENT.to_vec(),
-            value: utils::u256_to_bytes(U256::from(900u64)).to_vec(),
+            value: utils::u256_to_bytes(U256::from(500u64)).to_vec(),
         })
         .execute(&mut *conn)
         .await
@@ -256,11 +247,9 @@ async fn evaluate_passes_volume_at_exact_limit() {
 
     let grant = Grant {
         id: grant_id,
-        common_settings_id: basic.id,
+        shared_grant_id: basic.id,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings,
-            specific: settings,
-        },
     };
     let calldata = transfer_calldata(RECIPIENT, U256::from(100u64));
     let context = ctx(DAI, calldata);
@@ -285,14 +274,15 @@ async fn evaluate_rejects_volume_over_limit() {
         .await
         .unwrap();
 
-    insert_into(db::schema::evm_token_transfer_log::table)
+    use crate::db::{models::NewEvmTokenTransferLog, schema::evm_token_transfer_log};
-        .values(db::models::NewEvmTokenTransferLog {
+    insert_into(evm_token_transfer_log::table)
+        .values(NewEvmTokenTransferLog {
             grant_id,
             log_id: 0,
-            chain_id: CHAIN_ID.into(),
+            chain_id: CHAIN_ID as i32,
             token_contract: DAI.to_vec(),
             recipient_address: RECIPIENT.to_vec(),
-            value: utils::u256_to_bytes(U256::from(1_000u64)).to_vec(),
+            value: utils::u256_to_bytes(U256::from(1_001u64)).to_vec(),
         })
         .execute(&mut *conn)
         .await
@@ -300,13 +290,11 @@ async fn evaluate_rejects_volume_over_limit() {
 
     let grant = Grant {
         id: grant_id,
-        common_settings_id: basic.id,
+        shared_grant_id: basic.id,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings,
-            specific: settings,
-        },
     };
-    let calldata = transfer_calldata(RECIPIENT, U256::from(1u64));
+    let calldata = transfer_calldata(RECIPIENT, U256::from(100u64));
     let context = ctx(DAI, calldata);
     let m = TokenTransfer::analyze(&context).unwrap();
     let v = TokenTransfer::evaluate(&context, &m, &grant, &mut *conn)
@@ -325,11 +313,9 @@ async fn evaluate_no_volume_limits_always_passes() {
 
     let grant = Grant {
         id: 999,
-        common_settings_id: 999,
+        shared_grant_id: 999,
-        settings: CombinedSettings {
+        shared: shared(),
-            shared: shared(),
+        settings: make_settings(None, None), // no volume limits
-            specific: make_settings(None, None), // no volume limits
-        },
     };
     let calldata = transfer_calldata(RECIPIENT, U256::from(u64::MAX));
     let context = ctx(DAI, calldata);
@@ -363,13 +349,10 @@ async fn try_find_grant_roundtrip() {
 
     assert!(found.is_some());
     let g = found.unwrap();
-    assert_eq!(g.settings.specific.token_contract, DAI);
+    assert_eq!(g.settings.token_contract, DAI);
-    assert_eq!(g.settings.specific.target, Some(RECIPIENT));
+    assert_eq!(g.settings.target, Some(RECIPIENT));
-    assert_eq!(g.settings.specific.volume_limits.len(), 1);
+    assert_eq!(g.settings.volume_limits.len(), 1);
-    assert_eq!(
+    assert_eq!(g.settings.volume_limits[0].max_volume, U256::from(5_000u64));
-        g.settings.specific.volume_limits[0].max_volume,
-        U256::from(5_000u64)
-    );
 }
 
 #[tokio::test]
@@ -409,39 +392,7 @@ async fn try_find_grant_unknown_token_returns_none() {
     assert!(found.is_none());
 }
 
-proptest::proptest! {
+// ── find_all_grants ──────────────────────────────────────────────────────
-    #[test]
-    fn volume_limits_order_does_not_affect_hash(
-        raw_limits in proptest::collection::vec(
-            (proptest::prelude::any::<u64>(), 1i64..=86400),
-            0..8,
-        ),
-        seed in proptest::prelude::any::<u64>(),
-    ) {
-        use rand::{SeedableRng, seq::SliceRandom};
-        use sha2::Digest;
-        use arbiter_crypto::hashing::Hashable;
-
-        let limits: Vec<VolumeRateLimit> = raw_limits
-            .iter()
-            .map(|(max_vol, window_secs)| VolumeRateLimit {
-                max_volume: U256::from(*max_vol),
-                window: Duration::seconds(*window_secs),
-            })
-            .collect();
-
-        let mut shuffled = limits.clone();
-        shuffled.shuffle(&mut rand::rngs::StdRng::seed_from_u64(seed));
-
-        let mut h1 = sha2::Sha256::new();
-        Settings { token_contract: DAI, target: None, volume_limits: limits }.hash(&mut h1);
-
-        let mut h2 = sha2::Sha256::new();
-        Settings { token_contract: DAI, target: None, volume_limits: shuffled }.hash(&mut h2);
-
-        proptest::prop_assert_eq!(h1.finalize(), h2.finalize());
-    }
-}
 
 #[tokio::test]
 async fn find_all_grants_empty_db() {
@@ -483,9 +434,9 @@ async fn find_all_grants_loads_volume_limits() {
 
     let all = TokenTransfer::find_all_grants(&mut *conn).await.unwrap();
     assert_eq!(all.len(), 1);
-    assert_eq!(all[0].settings.specific.volume_limits.len(), 1);
+    assert_eq!(all[0].settings.volume_limits.len(), 1);
     assert_eq!(
-        all[0].settings.specific.volume_limits[0].max_volume,
+        all[0].settings.volume_limits[0].max_volume,
         U256::from(9_999u64)
     );
 }

server/crates/arbiter-server/src/evm/safe_signer.rs

@@ -1,5 +1,6 @@
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
+use std::sync::Mutex;
 
+use crate::safe_cell::{SafeCell, SafeCellHandle as _};
 use alloy::{
     consensus::SignableTransaction,
     network::{TxSigner, TxSignerSync},
@@ -8,7 +9,6 @@ use alloy::{
 };
 use async_trait::async_trait;
 use k256::ecdsa::{self, RecoveryId, SigningKey, signature::hazmat::PrehashSigner};
-use std::sync::Mutex;
 
 /// An Ethereum signer that stores its secp256k1 secret key inside a
 /// hardware-protected [`MemSafe`] cell.
@@ -82,8 +82,8 @@ impl SafeSigner {
         })
     }
 
-    #[expect(clippy::significant_drop_tightening, reason = "false positive")]
     fn sign_hash_inner(&self, hash: &B256) -> Result<Signature> {
+        #[allow(clippy::expect_used)]
         let mut cell = self.key.lock().expect("SafeSigner mutex poisoned");
         let reader = cell.read();
         let sig: (ecdsa::Signature, RecoveryId) = reader.sign_prehash(hash.as_ref())?;
@@ -96,6 +96,7 @@ impl SafeSigner {
         {
             return Err(Error::TransactionChainIdMismatch {
                 signer: chain_id,
+                #[allow(clippy::expect_used)]
                 tx: tx.chain_id().expect("Chain ID is guaranteed to be set"),
             });
         }

server/crates/arbiter-server/src/evm/utils.rs

@@ -2,20 +2,20 @@ use alloy::primitives::U256;
 
 #[derive(thiserror::Error, Debug)]
 #[error("Expected {expected} bytes but got {actual} bytes")]
-pub(super) struct LengthError {
+pub struct LengthError {
-    pub(super) expected: usize,
+    pub expected: usize,
-    pub(super) actual: usize,
+    pub actual: usize,
 }
 
-pub const fn u256_to_bytes(value: U256) -> [u8; 32] {
+pub fn u256_to_bytes(value: U256) -> [u8; 32] {
     value.to_le_bytes()
 }
-pub(super) fn bytes_to_u256(bytes: &[u8]) -> Option<U256> {
+pub fn bytes_to_u256(bytes: &[u8]) -> Option<U256> {
     let bytes: [u8; 32] = bytes.try_into().ok()?;
     Some(U256::from_le_bytes(bytes))
 }
 
-pub(super) fn try_bytes_to_u256(bytes: &[u8]) -> diesel::result::QueryResult<U256> {
+pub fn try_bytes_to_u256(bytes: &[u8]) -> diesel::result::QueryResult<U256> {
     let bytes: [u8; 32] = bytes.try_into().map_err(|_| {
         diesel::result::Error::DeserializationError(Box::new(LengthError {
             expected: 32,

server/crates/arbiter-server/src/grpc/client.rs

@@ -1,24 +1,32 @@
-use crate::{
-    grpc::request_tracker::RequestTracker,
-    peers::client::{ClientConnection, session::ClientSession},
-};
 use arbiter_proto::{
     proto::client::{
-        ClientRequest, ClientResponse, client_request::Payload as ClientRequestPayload,
+        ClientRequest, ClientResponse, VaultState as ProtoVaultState,
+        client_request::Payload as ClientRequestPayload,
         client_response::Payload as ClientResponsePayload,
     },
     transport::{Receiver, Sender, grpc::GrpcBi},
 };
-
+use kameo::{
-use kameo::actor::{ActorRef, Spawn as _};
+    actor::{ActorRef, Spawn as _},
+    error::SendError,
+};
 use tonic::Status;
 use tracing::{info, warn};
 
+use crate::{
+    actors::{
+        client::{
+            self, ClientConnection,
+            session::{ClientSession, Error, HandleQueryVaultState},
+        },
+        keyholder::KeyHolderState,
+    },
+    grpc::request_tracker::RequestTracker,
+};
+
 mod auth;
-mod evm;
 mod inbound;
 mod outbound;
-mod vault;
 
 async fn dispatch_loop(
     mut bi: GrpcBi<ClientRequest, ClientResponse>,
@@ -26,9 +34,7 @@ async fn dispatch_loop(
     mut request_tracker: RequestTracker,
 ) {
     loop {
-        let Some(message) = bi.recv().await else {
+        let Some(message) = bi.recv().await else { return };
-            return;
-        };
 
         let conn = match message {
             Ok(conn) => conn,
@@ -47,24 +53,16 @@ async fn dispatch_loop(
         };
 
         let Some(payload) = conn.payload else {
-            let _ = bi
+            let _ = bi.send(Err(Status::invalid_argument("Missing client request payload"))).await;
-                .send(Err(Status::invalid_argument(
-                    "Missing client request payload",
-                )))
-                .await;
             return;
         };
 
         match dispatch_inner(&actor, payload).await {
             Ok(response) => {
-                if bi
+                if bi.send(Ok(ClientResponse {
-                    .send(Ok(ClientResponse {
+                    request_id: Some(request_id),
-                        request_id: Some(request_id),
+                    payload: Some(response),
-                        payload: Some(response),
+                })).await.is_err() {
-                    }))
-                    .await
-                    .is_err()
-                {
                     return;
                 }
             }
@@ -81,10 +79,21 @@ async fn dispatch_inner(
     payload: ClientRequestPayload,
 ) -> Result<ClientResponsePayload, Status> {
     match payload {
-        ClientRequestPayload::Vault(req) => vault::dispatch(actor, req).await,
+        ClientRequestPayload::QueryVaultState(_) => {
-        ClientRequestPayload::Evm(req) => evm::dispatch(actor, req).await,
+            let state = match actor.ask(HandleQueryVaultState {}).await {
-        ClientRequestPayload::Auth(..) => {
+                Ok(KeyHolderState::Unbootstrapped) => ProtoVaultState::Unbootstrapped,
-            warn!("Unsupported post-auth client auth request");
+                Ok(KeyHolderState::Sealed) => ProtoVaultState::Sealed,
+                Ok(KeyHolderState::Unsealed) => ProtoVaultState::Unsealed,
+                Err(SendError::HandlerError(Error::Internal)) => ProtoVaultState::Error,
+                Err(err) => {
+                    warn!(error = ?err, "Failed to query vault state");
+                    ProtoVaultState::Error
+                }
+            };
+            Ok(ClientResponsePayload::VaultState(state.into()))
+        }
+        payload => {
+            warn!(?payload, "Unsupported post-auth client request");
             Err(Status::invalid_argument("Unsupported client request"))
         }
     }
@@ -93,20 +102,14 @@ async fn dispatch_inner(
 pub async fn start(mut conn: ClientConnection, mut bi: GrpcBi<ClientRequest, ClientResponse>) {
     let mut request_tracker = RequestTracker::default();
 
-    let client_id = match auth::start(&mut conn, &mut bi, &mut request_tracker).await {
+    if let Err(e) = auth::start(&mut conn, &mut bi, &mut request_tracker).await {
-        Ok(id) => id,
+        let mut transport = auth::AuthTransportAdapter::new(&mut bi, &mut request_tracker);
-        Err(err) => {
+        let _ = transport.send(Err(e.clone())).await;
-            let _ = bi
+        warn!(error = ?e, "Client authentication failed");
-                .send(Err(Status::unauthenticated(format!(
+        return;
-                    "Authentication failed: {err}",
-                ))))
-                .await;
-            warn!(error = ?err, "Client authentication failed");
-            return;
-        }
     };
 
-    let actor = ClientSession::spawn(ClientSession::new(conn, client_id));
+    let actor = client::session::ClientSession::spawn(client::session::ClientSession::new(conn));
     let actor_for_cleanup = actor.clone();
 
     info!("Client authenticated successfully");