feat(vault)!: implement full Shamir re-key flow and governance execution (§3.3–§3.5)

- Add `rekey.proto` with `ContributePassphrase` / `ContributeRecoveryPassphrase` / `RekeyResult`
- Wire `rekey` as a 4th vault stream payload in `vault.proto` and gRPC dispatch
- Add `RekeyRootKey` message to `Vault` actor: generates new random seal key, re-encrypts root key, writes new `root_key_history` row
- Add `StartRekey`, `ContributeRekey`, `ContributeRecoveryRekey` messages to `VaultCoordinator`; `finalize_rekey` uses threshold-1 fast path identical to bootstrap
- `execute_replace_operator` now UPDATEs `operator_identity.public_key` in-place (avoids FK constraint violation), deletes stale `operator` share row, then triggers `StartRekey`
- `execute_update_shamir_parameters` triggers `StartRekey` instead of warning stub
- `ProposalKind::ReplaceOperator` carries `old_operator_id`; encode/decode updated accordingly
- `GlobalActors::spawn` extracts `vault_coordinator` before `Ok(Self { … })` so it can be cloned into `ProposalManager::new`
- Add `handle_rekey` in session handlers forwarding passphrase contributions to `VaultCoordinator`
- Fix test: rename `replace_operator_inserts_identity_row` → `replace_operator_updates_pubkey_and_starts_rekey`, assert count stays 1 and pubkey is updated

.gitignore

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

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
-- **`useragent/`** — Flutter desktop app (macOS/Windows) with a Rust backend via Rinf
+- **`operator/`** — 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-useragent` | Rust client library for the user agent side of the gRPC protocol |
+| `arbiter-operator` | Rust client library for the operator 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.
-- **`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.
+- **`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.
+- **`FlowCoordinator`** — Coordinates cross-connection flow between operators 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.
+Per-connection actors live under `actors/operator/` 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()`.
 
@@ -121,20 +121,20 @@ pub fn verify(&self, nonce: i32, context: &[u8], signature: &Signature) -> bool
 
 This forces callers to either use the return value or explicitly ignore it with `let _ = ...;`, preventing silent failures.
 
-## User Agent (Flutter + Rinf at `useragent/`)
+## Operator (Flutter + Rinf at `operator/`)
 
-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.
+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 `useragent/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
+Communication between Dart and Rust uses typed **signals** defined in `operator/native/hub/src/signals/`. After modifying signal structs, regenerate Dart bindings:
 
 ```sh
-cd useragent && rinf gen
+cd operator && rinf gen
 ```
 
 ### Common Commands
 
 ```sh
-cd useragent
+cd operator
 
 # Run the app (macOS or Windows)
 flutter run
@@ -146,4 +146,4 @@ rinf gen
 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.
+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.

CLAUDE.md

@@ -1,149 +1 @@
-# 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
-```
-
-### Code Conventions
-
-**`#[must_use]` Attribute:**
-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
-- 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.
-
-## 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.
+Refer to @AGENTS.md for instructions.

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 user agent challenge solutions
+- Pretends to be server; just accepts operator challenge solutions
 - Pretend to be in sealed state and performing DH with client
 - Steals user password and derives seal key
 

docs/ARCHITECTURE.md

@@ -9,7 +9,7 @@ Arbiter is a permissioned signing service for cryptocurrency wallets. It runs as
 
 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).
+- **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.
 
@@ -22,30 +22,32 @@ Arbiter distinguishes two kinds of peers:
 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.
+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.
 
-### 2.2 User Agent Bootstrap
+Authentication challenges are per-connection, ephemeral values. They are not persisted in the peer tables, and peer records store no challenge state.
 
-On first run — when no User Agents are registered — the server generates a one-time bootstrap token. It is made available in two ways:
+### 2.2 Operator Bootstrap
 
-- **Local setup:** Written to `~/.arbiter/bootstrap_token` for automatic discovery by a co-located User Agent.
+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 User Agent must present this token alongside the standard challenge-response to complete registration.
+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 User Agent.
+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 User Agent 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.
+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
 
@@ -163,13 +165,13 @@ In both cases, committee formation is a coordinated process. Arbiter does not al
 
 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 a User Agent and the bootstrap token.
+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 a User Agent using the bootstrap token
+   - 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
@@ -191,8 +193,8 @@ The server proves its identity using TLS with a self-signed certificate. The TLS
 
 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.
+- **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.
 
@@ -229,11 +231,11 @@ On boot, the root key is encrypted and the server cannot perform any signing ope
 
 ### 6.2 Unseal Flow
 
-To transition to the **Unsealed** state, a User Agent must provide the password:
+To transition to the **Unsealed** state, an Operator must provide the password:
 
-1. The User Agent initiates an unseal request.
+1. The Operator 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.
+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.
@@ -255,7 +257,7 @@ See [IMPLEMENTATION.md](IMPLEMENTATION.md) for the current and planned memory pr
 ### 7.1 Fundamental Rules
 
 - SDK clients have **no access by default**.
-- Access is granted **explicitly** by a User Agent.
+- 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.
@@ -275,19 +277,19 @@ sequenceDiagram
     autonumber
     actor SDK as SDK Client
     participant Server
-    participant UA as User Agent
+    participant operator as Operator
 
     SDK->>Server: SignTransactionRequest
     Server->>Server: Resolve wallet and wallet visibility
     alt Visibility approval required
-        Server->>UA: Ask for wallet visibility approval
-        UA-->>Server: Vote result
+        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->>UA: Ask for execution / grant approval
-        UA-->>Server: Vote result
+        Server->>operator: Ask for execution / grant approval
+        operator-->>Server: Vote result
         opt Create persistent grant
             Server->>Server: Create and store grant
         end

docs/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 `user-agent` return explicit auth status enums over the wire.
+Authentication no longer uses an implicit success-only response shape. Both `client` and `operator` return explicit auth status enums over the wire.
 
-- **Client:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `APPROVAL_DENIED`, `NO_USER_AGENTS_ONLINE`, or `INTERNAL`
-- **User-agent:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `BOOTSTRAP_REQUIRED`, `TOKEN_INVALID`, or `INTERNAL`
+- **Client:** `AuthResult` may return `SUCCESS`, `INVALID_KEY`, `INVALID_SIGNATURE`, `APPROVAL_DENIED`, `NO_OPERATORS_ONLINE`, or `INTERNAL`
+- **Operator:** `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:
 
@@ -22,45 +22,36 @@ 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 user agents are asked to approve the connection. The first agent 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 operators are asked to approve the connection. The first operator 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 --> D[Read nonce\nIncrement nonce in DB]
-    D --> G
+    C -- yes --> G[Generate AuthChallenge]
 
-    C -- no --> E[Ask all UserAgents:\nClientConnectionRequest]
+    C -- no --> E[Ask all Operators:\nClientConnectionRequest]
     E --> F{First response}
     F -- denied --> Z([Reject connection])
-    F -- approved --> F2[Cancel remaining\nUserAgent requests]
-    F2 --> F3[INSERT client\nnonce = 1]
-    F3 --> G[Send AuthChallenge\nwith nonce]
+    F -- approved --> F2[Cancel remaining\nOperator requests]
+    F2 --> F3[INSERT client]
+    F3 --> G
 
-    G --> H[Receive AuthChallengeSolution]
-    H --> I{Signature valid?}
-    I -- no --> Z
-    I -- yes --> J([Session started])
+    G --> H[Send AuthChallenge\ntimestamp + random bytes]
+    H --> I[Receive AuthChallengeSolution]
+    I --> K{Signature valid?}
+    K -- no --> Z
+    K -- yes --> J([Session started])
 ```
 
-### Known Issue: Concurrent Registration Race (TOCTOU)
+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.
 
-Two connections presenting the same previously-unknown public key can race through the approval flow simultaneously:
+The authentication schema stores peer identity, not replay counters:
 
-1. Both check the DB → neither is registered.
-2. Both request approval from user agents → both receive approval.
-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.
+- `program_client` stores the SDK client's public key, metadata binding, and timestamps.
+- `operator_client` stores the Operator public key and timestamps.
+- Neither table stores an authentication nonce, and challenge generation does not update either table.
 
 ---
 
@@ -71,7 +62,7 @@ The `program_client.nonce` column stores the **next usable nonce** — i.e. it i
 
 ### User-Agent Authentication
 
-User-agent authentication supports multiple signature schemes because platform-provided "hardware-bound" keys do not expose a uniform algorithm across operating systems and hardware.
+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
@@ -95,7 +86,7 @@ User-agent authentication supports multiple signature schemes because platform-p
 
 ### Request Multiplexing
 
-Both `client` and `user-agent` connections support multiple in-flight requests over one gRPC bidi stream.
+Both `client` and `operator` 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
@@ -150,7 +141,7 @@ flowchart TD
     L -- Yes --> M[Check grant limits]
     L -- No --> N[Start execution or grant voting flow]
 
-    N --> O{User-agent decision}
+    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]

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

@@ -111,7 +111,7 @@ String shortAddress(List<int> bytes) {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd useragent && dart analyze lib/screens/dashboard/evm/grants/create/utils.dart
+cd operator && 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 useragent && dart run build_runner build --delete-conflicting-outputs
+cd operator && 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 useragent && dart analyze lib/screens/dashboard/evm/grants/create/provider.dart
+cd operator && 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/user_agent.pb.dart';
+import 'package:arbiter/proto/operator.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/user_agent.pb.dart';
+import 'package:arbiter/proto/operator.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 useragent && dart analyze lib/screens/dashboard/evm/grants/create/fields/
+cd operator && 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 useragent && dart analyze lib/screens/dashboard/evm/grants/create/shared_grant_fields.dart
+cd operator && 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 useragent && dart run build_runner build --delete-conflicting-outputs
+cd operator && 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 useragent && dart analyze lib/screens/dashboard/evm/grants/create/grants/
+cd operator && 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 useragent && dart analyze lib/screens/dashboard/evm/grants/create/
+cd operator && 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 |
 |---|---|---|
-| `useragent/lib/theme/palette.dart` | Modify | Add `Palette.token` (indigo accent for token-transfer cards) |
-| `useragent/lib/features/connection/evm/wallet_access.dart` | Modify | Add `listAllWalletAccesses()` function |
-| `useragent/lib/providers/sdk_clients/wallet_access_list.dart` | Create | `WalletAccessListProvider` — fetches full wallet access list with IDs |
-| `useragent/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/grants.dart` | Create | `EvmGrantsScreen` — watches `evmGrantsProvider`; handles loading/error/empty/data states; renders `GrantCard` list |
-| `useragent/lib/router.dart` | Modify | Register `EvmGrantsRoute` in dashboard children |
-| `useragent/lib/screens/dashboard.dart` | Modify | Add Grants entry to `routes` list and `NavigationDestination` list |
+| `operator/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 |
+| `operator/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 |
+| `operator/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 |
+| `operator/lib/screens/dashboard.dart` | Modify | Add Grants entry to `routes` list and `NavigationDestination` list |
 
 ---
 
 ## Task 1: Add `Palette.token`
 
 **Files:**
-- Modify: `useragent/lib/theme/palette.dart`
+- Modify: `operator/lib/theme/palette.dart`
 
 - [ ] **Step 1: Add the color**
 
-Replace the contents of `useragent/lib/theme/palette.dart` with:
+Replace the contents of `operator/lib/theme/palette.dart` with:
 
 ```dart
 import 'package:flutter/material.dart';
@@ -48,7 +48,7 @@ class Palette {
 - [ ] **Step 2: Verify**
 
 ```sh
-cd useragent && flutter analyze lib/theme/palette.dart
+cd operator && flutter analyze lib/theme/palette.dart
 ```
 
 Expected: no issues.
@@ -65,20 +65,20 @@ jj new
 ## Task 2: Add `listAllWalletAccesses` feature function
 
 **Files:**
-- Modify: `useragent/lib/features/connection/evm/wallet_access.dart`
+- Modify: `operator/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 `useragent/lib/features/connection/evm/wallet_access.dart`:
+Add at the bottom of `operator/lib/features/connection/evm/wallet_access.dart`:
 
 ```dart
 Future<List<SdkClientWalletAccess>> listAllWalletAccesses(
   Connection connection,
 ) async {
   final response = await connection.ask(
-    UserAgentRequest(listWalletAccess: Empty()),
+    OperatorRequest(listWalletAccess: Empty()),
   );
   if (!response.hasListWalletAccessResponse()) {
     throw Exception(
@@ -97,7 +97,7 @@ Each returned `SdkClientWalletAccess` has:
 - [ ] **Step 2: Verify**
 
 ```sh
-cd useragent && flutter analyze lib/features/connection/evm/wallet_access.dart
+cd operator && flutter analyze lib/features/connection/evm/wallet_access.dart
 ```
 
 Expected: no issues.
@@ -114,18 +114,18 @@ jj new
 ## Task 3: Create `WalletAccessListProvider`
 
 **Files:**
-- Create: `useragent/lib/providers/sdk_clients/wallet_access_list.dart`
-- Generated: `useragent/lib/providers/sdk_clients/wallet_access_list.g.dart`
+- Create: `operator/lib/providers/sdk_clients/wallet_access_list.dart`
+- Generated: `operator/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 `useragent/lib/providers/sdk_clients/wallet_access_list.dart`:
+Create `operator/lib/providers/sdk_clients/wallet_access_list.dart`:
 
 ```dart
 import 'package:arbiter/features/connection/evm/wallet_access.dart';
-import 'package:arbiter/proto/user_agent.pb.dart';
+import 'package:arbiter/proto/operator.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 useragent && dart run build_runner build --delete-conflicting-outputs
+cd operator && dart run build_runner build --delete-conflicting-outputs
 ```
 
-Expected: `useragent/lib/providers/sdk_clients/wallet_access_list.g.dart` created. No errors.
+Expected: `operator/lib/providers/sdk_clients/wallet_access_list.g.dart` created. No errors.
 
 - [ ] **Step 3: Verify**
 
 ```sh
-cd useragent && flutter analyze lib/providers/sdk_clients/
+cd operator && flutter analyze lib/providers/sdk_clients/
 ```
 
 Expected: no issues.
@@ -190,26 +190,26 @@ jj new
 ## Task 4: Create `GrantCard` widget
 
 **Files:**
-- Create: `useragent/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`
+- Create: `operator/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/user_agent.pb.dart`): `.id`, `.access.walletId`, `.access.sdkClientId`
+- `SdkClientWalletAccess` (from `proto/operator.pb.dart`): `.id`, `.access.walletId`, `.access.sdkClientId`
 - `WalletEntry` (from `proto/evm.pb.dart`): `.id`, `.address` (List<int>)
-- `SdkClientEntry` (from `proto/user_agent.pb.dart`): `.id`, `.info.name`
+- `SdkClientEntry` (from `proto/operator.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 `useragent/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`:
+Create `operator/lib/screens/dashboard/evm/grants/widgets/grant_card.dart`:
 
 ```dart
 import 'package:arbiter/proto/evm.pb.dart';
-import 'package:arbiter/proto/user_agent.pb.dart';
+import 'package:arbiter/proto/operator.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 useragent && flutter analyze lib/screens/dashboard/evm/grants/widgets/grant_card.dart
+cd operator && 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: `useragent/lib/screens/dashboard/evm/grants/grants.dart`
+- Create: `operator/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 `useragent/lib/screens/dashboard/evm/grants/grants.dart`:
+Create `operator/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 useragent && flutter analyze lib/screens/dashboard/evm/grants/
+cd operator && 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: `useragent/lib/router.dart`
-- Modify: `useragent/lib/screens/dashboard.dart`
-- Regenerated: `useragent/lib/router.gr.dart`
+- Modify: `operator/lib/router.dart`
+- Modify: `operator/lib/screens/dashboard.dart`
+- Regenerated: `operator/lib/router.gr.dart`
 
 - [ ] **Step 1: Add route to `router.dart`**
 
-Replace the contents of `useragent/lib/router.dart` with:
+Replace the contents of `operator/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 `useragent/lib/screens/dashboard.dart`, replace the `routes` constant:
+In `operator/lib/screens/dashboard.dart`, replace the `routes` constant:
 
 ```dart
 final routes = [
@@ -800,7 +800,7 @@ destinations: const [
 - [ ] **Step 3: Regenerate router**
 
 ```sh
-cd useragent && dart run build_runner build --delete-conflicting-outputs
+cd operator && 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 useragent && flutter analyze
+cd operator && 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 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.
+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.
 
 ## Scope
 
@@ -23,7 +23,7 @@ Add a "Grants" dashboard tab to the Flutter user-agent app that displays all EVM
 
 ### `walletAccessListProvider`
 
-**File:** `useragent/lib/providers/sdk_clients/wallet_access_list.dart`
+**File:** `operator/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:** `useragent/lib/screens/dashboard/evm/grants/grants.dart`
+**File:** `operator/lib/screens/dashboard/evm/grants/grants.dart`
 
 ```
 Scaffold

mise.lock

@@ -1,51 +1,51 @@
 # @generated - this file is auto-generated by `mise lock` https://mise.jdx.dev/dev-tools/mise-lock.html
 
 [[tools.ast-grep]]
-version = "0.42.0"
+version = "0.42.1"
 backend = "aqua:ast-grep/ast-grep"
 
 [tools.ast-grep."platforms.linux-arm64"]
-checksum = "sha256:5c830eae8456569e2f7212434ed9c238f58dca412d76045418ed6d394a755836"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-unknown-linux-gnu.zip"
+checksum = "sha256:3ba383839044cf9817929435f5ce0027f91d06931e8efb32d942e58d73d92be5"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-arm64-musl"]
-checksum = "sha256:5c830eae8456569e2f7212434ed9c238f58dca412d76045418ed6d394a755836"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-unknown-linux-gnu.zip"
+checksum = "sha256:3ba383839044cf9817929435f5ce0027f91d06931e8efb32d942e58d73d92be5"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-x64"]
-checksum = "sha256:e825a05603f0bcc4cd9076c4cc8c9abd6d008b7cd07d9aa3cc323ba4b8606651"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-unknown-linux-gnu.zip"
+checksum = "sha256:5de8b87cba67fc8dc3e239d54b6484802ad745a7ae3de76be4fe89661dc52657"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.linux-x64-musl"]
-checksum = "sha256:e825a05603f0bcc4cd9076c4cc8c9abd6d008b7cd07d9aa3cc323ba4b8606651"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-unknown-linux-gnu.zip"
+checksum = "sha256:5de8b87cba67fc8dc3e239d54b6484802ad745a7ae3de76be4fe89661dc52657"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-unknown-linux-gnu.zip"
 
 [tools.ast-grep."platforms.macos-arm64"]
-checksum = "sha256:fc300d5293b1c770a5aece03a8a193b92e71e87cec726c28096990691a582620"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-aarch64-apple-darwin.zip"
+checksum = "sha256:c3961d8e8a4ee0ce2d0d98c7beeb168bb331cdc766b53630118a7b6c4fd39015"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-aarch64-apple-darwin.zip"
 
 [tools.ast-grep."platforms.macos-x64"]
-checksum = "sha256:979ffe611327056f4730a1ae71b0209b3b830f58b22c6ed194cda34f55400db2"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-apple-darwin.zip"
+checksum = "sha256:a038965bfd7fe44257c771cdf8918dc3467dd8ec0eef673b8b14f639b144cdbd"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-apple-darwin.zip"
 
 [tools.ast-grep."platforms.windows-x64"]
-checksum = "sha256:55836fa1b2c65dc7d61615a4d9368622a0d2371a76d28b9a165e5a3ab6ae32a4"
-url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.0/app-x86_64-pc-windows-msvc.zip"
+checksum = "sha256:fe34f631bb24c08ad146f92ca2a92971a53d179461b509fd8d32dc863bff9f83"
+url = "https://github.com/ast-grep/ast-grep/releases/download/0.42.1/app-x86_64-pc-windows-msvc.zip"
 
 [[tools."cargo:cargo-audit"]]
 version = "0.22.1"
 backend = "cargo:cargo-audit"
 
 [[tools."cargo:cargo-edit"]]
-version = "0.13.9"
+version = "0.13.10"
 backend = "cargo:cargo-edit"
 
 [[tools."cargo:cargo-features-manager"]]
-version = "0.11.1"
+version = "0.12.0"
 backend = "cargo:cargo-features-manager"
 
 [[tools."cargo:cargo-insta"]]
-version = "1.46.3"
+version = "1.47.2"
 backend = "cargo:cargo-insta"
 
 [[tools."cargo:cargo-mutants"]]
@@ -53,7 +53,7 @@ version = "27.0.0"
 backend = "cargo:cargo-mutants"
 
 [[tools."cargo:cargo-nextest"]]
-version = "0.9.126"
+version = "0.9.133"
 backend = "cargo:cargo-nextest"
 
 [[tools."cargo:cargo-shear"]]
@@ -65,15 +65,19 @@ version = "0.10.2"
 backend = "cargo:cargo-vet"
 
 [[tools."cargo:diesel_cli"]]
-version = "2.3.6"
+version = "2.3.7"
 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 = "3.38.9-stable"
+version = "3.41.7-stable"
 backend = "asdf:flutter"
 
 [[tools.protoc]]
@@ -109,44 +113,44 @@ checksum = "sha256:1ebd7c87baffb9f1c47169b640872bf5fb1e4408079c691af527be9561d8f
 url = "https://github.com/protocolbuffers/protobuf/releases/download/v29.6/protoc-29.6-win64.zip"
 
 [[tools.python]]
-version = "3.14.3"
+version = "3.14.4"
 backend = "core:python"
 
 [tools.python."platforms.linux-arm64"]
-checksum = "sha256:53700338695e402a1a1fe22be4a41fbdacc70e22bb308a48eca8ed67cb7992be"
-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"
+checksum = "sha256:b8b597fdb2f8dccdc502c11947b60a4b65eb6bce79cfa60c7ccf9b6e8352c60a"
+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"
 provenance = "github-attestations"
 
 [tools.python."platforms.linux-arm64-musl"]
-checksum = "sha256:53700338695e402a1a1fe22be4a41fbdacc70e22bb308a48eca8ed67cb7992be"
-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"
+checksum = "sha256:b8b597fdb2f8dccdc502c11947b60a4b65eb6bce79cfa60c7ccf9b6e8352c60a"
+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"
 provenance = "github-attestations"
 
 [tools.python."platforms.linux-x64"]
-checksum = "sha256:d7a9f970914bb4c88756fe3bdcc186d4feb90e9500e54f1db47dae4dc9687e39"
-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"
+checksum = "sha256:fe9a9c32d13870af632cbac3dfc7528ae53597e94472aa4c7d6a42e8166136cd"
+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"
 provenance = "github-attestations"
 
 [tools.python."platforms.linux-x64-musl"]
-checksum = "sha256:d7a9f970914bb4c88756fe3bdcc186d4feb90e9500e54f1db47dae4dc9687e39"
-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"
+checksum = "sha256:fe9a9c32d13870af632cbac3dfc7528ae53597e94472aa4c7d6a42e8166136cd"
+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"
 provenance = "github-attestations"
 
 [tools.python."platforms.macos-arm64"]
-checksum = "sha256:c43aecde4a663aebff99b9b83da0efec506479f1c3f98331442f33d2c43501f9"
-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"
+checksum = "blake3:0314ec66e0f33ec04959583b5900bc8edae371a396aa96b8874e750d1fe936e6"
+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"
 provenance = "github-attestations"
 
 [tools.python."platforms.macos-x64"]
-checksum = "sha256:9ab41dbc2f100a2a45d1833b9c11165f51051c558b5213eda9a9731d5948a0c0"
-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"
+checksum = "sha256:d51250a32fa5d9f0799c7bcb71720c27b10a3afd4a7de288120f96085d508a5a"
+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"
 provenance = "github-attestations"
 
 [tools.python."platforms.windows-x64"]
-checksum = "sha256:bbe19034b35b0267176a7442575ae7dc6343480fd4d35598cb7700173d431e09"
-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"
+checksum = "sha256:a976991dcd085c1bb5d9a8084823a6bc8b7f9b079d8c432574a6ddd68c3a6fe1"
+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"
 provenance = "github-attestations"
 
 [[tools.rust]]
-version = "1.93.0"
+version = "1.95.0"
 backend = "core:rust"

mise.toml

@@ -1,18 +1,19 @@
 [tools]
-"cargo:diesel_cli" = { version = "2.3.6", features = "sqlite,sqlite-bundled", default-features = false }
+"cargo:diesel_cli" = { version = "2.3.7", features = "sqlite,sqlite-bundled", default-features = "false" }
 "cargo:cargo-audit" = "0.22.1"
 "cargo:cargo-vet" = "0.10.2"
-flutter = "3.38.9-stable"
+flutter = "3.41.7-stable"
 protoc = "29.6"
-"rust" = {version = "1.93.0", components = "clippy"}
-"cargo:cargo-features-manager" = "0.11.1"
-"cargo:cargo-nextest" = "0.9.126"
+rust = { version = "1.95.0", components = "clippy,rust-analyzer" }
+"cargo:cargo-features-manager" = "0.12.0"
+"cargo:cargo-nextest" = "0.9.133"
 "cargo:cargo-shear" = "latest"
-"cargo:cargo-insta" = "1.46.3"
-python = "3.14.3"
-ast-grep = "0.42.0"
-"cargo:cargo-edit" = "0.13.9"
+"cargo:cargo-insta" = "1.47.2"
+python = "3.14.4"
+ast-grep = "0.42.1"
+"cargo:cargo-edit" = "0.13.10"
 "cargo:cargo-mutants" = "27.0.0"
+"cargo:flutter_rust_bridge_codegen" = "2.12.0"
 
 [tasks.codegen]
 sources = ['protobufs/*.proto', 'protobufs/**/*.proto']
@@ -21,3 +22,5 @@ run = '''
 dart pub global activate protoc_plugin && \
 protoc --dart_out=grpc:useragent/lib/proto --proto_path=protobufs/ $(find protobufs -name '*.proto' | sort)
 '''
+
+[tasks.generate_schema]

protobufs/arbiter.proto

@@ -3,7 +3,7 @@ syntax = "proto3";
 package arbiter;
 
 import "client.proto";
-import "user_agent.proto";
+import "operator.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 UserAgent(stream arbiter.user_agent.UserAgentRequest) returns (stream arbiter.user_agent.UserAgentResponse);
+  rpc Operator(stream arbiter.operator.OperatorRequest) returns (stream arbiter.operator.OperatorResponse);
 }

protobufs/client/auth.proto

@@ -10,8 +10,8 @@ message AuthChallengeRequest {
 }
 
 message AuthChallenge {
-  bytes pubkey = 1;
-  int32 nonce = 2;
+  uint64 timestamp_nanos = 1;
+  bytes random = 2;
 }
 
 message AuthChallengeSolution {
@@ -24,7 +24,7 @@ enum AuthResult {
   AUTH_RESULT_INVALID_KEY = 2;
   AUTH_RESULT_INVALID_SIGNATURE = 3;
   AUTH_RESULT_APPROVAL_DENIED = 4;
-  AUTH_RESULT_NO_USER_AGENTS_ONLINE = 5;
+  AUTH_RESULT_NO_OPERATORS_ONLINE = 5;
   AUTH_RESULT_INTERNAL = 6;
 }
 

protobufs/evm.proto

@@ -75,7 +75,7 @@ message SpecificGrant {
   }
 }
 
-// --- UserAgent grant management ---
+// --- Operator grant management ---
 message EvmGrantCreateRequest {
   SharedSettings shared = 1;
   SpecificGrant specific = 2;

protobufs/operator.proto

@@ -0,0 +1,31 @@
+syntax = "proto3";
+
+package arbiter.operator;
+
+import "operator/auth.proto";
+import "operator/evm.proto";
+import "operator/governance.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;
+    governance.Request      governance  = 5;
+  }
+}
+
+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;
+    governance.Response     governance  = 5;
+  }
+}

protobufs/operator/auth.proto

@@ -1,22 +1,15 @@
 syntax = "proto3";
 
-package arbiter.user_agent.auth;
-
-enum KeyType {
-  KEY_TYPE_UNSPECIFIED = 0;
-  KEY_TYPE_ED25519 = 1;
-  KEY_TYPE_ECDSA_SECP256K1 = 2;
-  KEY_TYPE_RSA = 3;
-}
+package arbiter.operator.auth;
 
 message AuthChallengeRequest {
   bytes pubkey = 1;
   optional string bootstrap_token = 2;
-  KeyType key_type = 3;
 }
 
 message AuthChallenge {
-  int32 nonce = 1;
+  uint64 timestamp_nanos = 1;
+  bytes random = 2;
 }
 
 message AuthChallengeSolution {

protobufs/operator/evm.proto

@@ -1,6 +1,6 @@
 syntax = "proto3";
 
-package arbiter.user_agent.evm;
+package arbiter.operator.evm;
 
 import "evm.proto";
 import "google/protobuf/empty.proto";

protobufs/operator/governance.proto

@@ -0,0 +1,136 @@
+syntax = "proto3";
+
+package arbiter.operator.governance;
+
+message Request {
+  oneof payload {
+    CreateProposalRequest create = 1;
+    CastVoteRequest       vote   = 2;
+    QueryPendingRequest   query  = 3;
+  }
+}
+
+message CreateProposalRequest {
+  oneof kind {
+    ApproveSdkClientPayload         approve_sdk_client          = 1;
+    GrantWalletAccessPayload        grant_wallet_access         = 3;
+    ApproveServerUpdatePayload      approve_server_update       = 4;
+    ReplaceOperatorPayload          replace_operator            = 5;
+    UpdateShamirParametersPayload   update_shamir_parameters    = 6;
+    ApprovePersistentGrantPayload   approve_persistent_grant    = 7;
+    ApproveOneOffTransactionPayload approve_one_off_transaction = 8;
+  }
+  optional uint32 ttl_secs = 2;
+}
+
+message ReplaceOperatorPayload {
+  int32 old_operator_id = 1;
+  bytes new_pubkey      = 2;
+}
+
+message UpdateShamirParametersPayload {
+  uint32 new_n = 1;
+}
+
+message ApproveServerUpdatePayload {}
+
+message ApproveSdkClientPayload {
+  int32 client_id = 1;
+}
+
+message GrantWalletAccessPayload {
+  int32 wallet_id = 1;
+  int32 client_id = 2;
+}
+
+message CastVoteRequest {
+  int32 proposal_id = 1;
+  bool  approve     = 2;
+  bytes signature   = 3;
+}
+
+message QueryPendingRequest {}
+
+message Response {
+  oneof payload {
+    CreateProposalResponse created = 1;
+    VoteResponse           voted   = 2;
+    QueryPendingResponse   pending = 3;
+  }
+}
+
+message CreateProposalResponse {
+  int32 proposal_id = 1;
+}
+
+message VoteResponse {
+  VoteOutcome outcome = 1;
+}
+
+enum VoteOutcome {
+  VOTE_OUTCOME_UNSPECIFIED = 0;
+  VOTE_OUTCOME_PENDING     = 1;
+  VOTE_OUTCOME_APPROVED    = 2;
+  VOTE_OUTCOME_REJECTED    = 3;
+}
+
+message ProposalSummary {
+  int32  id            = 1;
+  string kind          = 2;
+  int32  initiator_id  = 3;
+  int64  expires_at    = 4;
+  int64  approve_count = 5;
+  int64  reject_count  = 6;
+}
+
+message QueryPendingResponse {
+  repeated ProposalSummary proposals = 1;
+}
+
+message TransactionRateLimitProto {
+  uint32 count       = 1;
+  int64  window_secs = 2;
+}
+
+message VolumeLimitProto {
+  bytes max_volume  = 1;
+  int64 window_secs = 2;
+}
+
+message EtherTransferSpecProto {
+  repeated bytes   targets = 1;
+  VolumeLimitProto limit   = 2;
+}
+
+message TokenTransferSpecProto {
+  bytes                     token_contract = 1;
+  optional bytes            target         = 2;
+  repeated VolumeLimitProto volume_limits  = 3;
+}
+
+message ApproveOneOffTransactionPayload {
+  int32  client_id                = 1;
+  bytes  wallet_address           = 2;
+  uint64 chain_id                 = 3;
+  uint64 nonce                    = 4;
+  uint64 gas_limit                = 5;
+  bytes  max_fee_per_gas          = 6;
+  bytes  max_priority_fee_per_gas = 7;
+  bytes  to                       = 8;
+  bytes  value                    = 9;
+  bytes  input                    = 10;
+}
+
+message ApprovePersistentGrantPayload {
+  int32                              wallet_access_id         = 1;
+  uint64                             chain_id                 = 2;
+  optional int64                     valid_from_secs          = 3;
+  optional int64                     valid_until_secs         = 4;
+  optional bytes                     max_gas_fee_per_gas      = 5;
+  optional bytes                     max_priority_fee_per_gas = 6;
+  optional TransactionRateLimitProto rate_limit               = 7;
+  oneof specific {
+    EtherTransferSpecProto ether_transfer = 8;
+    TokenTransferSpecProto token_transfer = 9;
+  }
+}

protobufs/operator/sdk_client.proto

@@ -1,6 +1,6 @@
 syntax = "proto3";
 
-package arbiter.user_agent.sdk_client;
+package arbiter.operator.sdk_client;
 
 import "shared/client.proto";
 import "google/protobuf/empty.proto";

protobufs/operator/vault/bootstrap.proto

@@ -0,0 +1,44 @@
+syntax = "proto3";
+
+package arbiter.operator.vault.bootstrap;
+
+message BootstrapEncryptedKey {
+  bytes nonce = 1;
+  bytes ciphertext = 2;
+  bytes associated_data = 3;
+}
+
+message DeclareCommittee {
+  uint32 count          = 1;
+  uint32 recovery_count = 2;
+}
+
+message ContributePassphrase {
+  bytes passphrase = 1;
+}
+
+message ContributeRecoveryPassphrase {
+  int32 recovery_operator_id = 1;
+  bytes passphrase            = 2;
+}
+
+enum BootstrapResult {
+  BOOTSTRAP_RESULT_UNSPECIFIED = 0;
+  BOOTSTRAP_RESULT_SUCCESS = 1;
+  BOOTSTRAP_RESULT_ALREADY_BOOTSTRAPPED = 2;
+  BOOTSTRAP_RESULT_INVALID_KEY = 3;
+  BOOTSTRAP_RESULT_AWAITING_CONTRIBUTIONS = 4;
+}
+
+message Request {
+  oneof payload {
+    BootstrapEncryptedKey        encrypted_key                    = 2;
+    DeclareCommittee             declare_committee                = 3;
+    ContributePassphrase         contribute_passphrase            = 4;
+    ContributeRecoveryPassphrase contribute_recovery_passphrase   = 5;
+  }
+}
+
+message Response {
+  BootstrapResult result = 1;
+}

protobufs/operator/vault/rekey.proto

@@ -0,0 +1,30 @@
+syntax = "proto3";
+
+package arbiter.operator.vault.rekey;
+
+message ContributePassphrase {
+  bytes passphrase = 1;
+}
+
+message ContributeRecoveryPassphrase {
+  int32 recovery_operator_id = 1;
+  bytes passphrase           = 2;
+}
+
+enum RekeyResult {
+  REKEY_RESULT_UNSPECIFIED            = 0;
+  REKEY_RESULT_SUCCESS                = 1;
+  REKEY_RESULT_AWAITING_CONTRIBUTIONS = 2;
+  REKEY_RESULT_NOT_IN_PROGRESS        = 3;
+}
+
+message Request {
+  oneof payload {
+    ContributePassphrase         contribute_passphrase          = 1;
+    ContributeRecoveryPassphrase contribute_recovery_passphrase = 2;
+  }
+}
+
+message Response {
+  RekeyResult result = 1;
+}

protobufs/operator/vault/unseal.proto

@@ -1,6 +1,6 @@
 syntax = "proto3";
 
-package arbiter.user_agent.vault.unseal;
+package arbiter.operator.vault.unseal;
 
 message UnsealStart {
   bytes client_pubkey = 1;
@@ -15,17 +15,29 @@ message UnsealEncryptedKey {
   bytes associated_data = 3;
 }
 
+message ContributePassphrase {
+  bytes passphrase = 1;
+}
+
+message ContributeRecoveryPassphrase {
+  int32 recovery_operator_id = 1;
+  bytes passphrase            = 2;
+}
+
 enum UnsealResult {
   UNSEAL_RESULT_UNSPECIFIED = 0;
   UNSEAL_RESULT_SUCCESS = 1;
   UNSEAL_RESULT_INVALID_KEY = 2;
   UNSEAL_RESULT_UNBOOTSTRAPPED = 3;
+  UNSEAL_RESULT_AWAITING_CONTRIBUTIONS = 4;
 }
 
 message Request {
   oneof payload {
-    UnsealStart start = 1;
-    UnsealEncryptedKey encrypted_key = 2;
+    UnsealStart                  start                          = 1;
+    UnsealEncryptedKey           encrypted_key                  = 2;
+    ContributePassphrase         contribute_passphrase          = 3;
+    ContributeRecoveryPassphrase contribute_recovery_passphrase = 4;
   }
 }
 

protobufs/operator/vault/vault.proto

@@ -0,0 +1,27 @@
+syntax = "proto3";
+
+package arbiter.operator.vault;
+
+import "google/protobuf/empty.proto";
+import "shared/vault.proto";
+import "operator/vault/bootstrap.proto";
+import "operator/vault/rekey.proto";
+import "operator/vault/unseal.proto";
+
+message Request {
+  oneof payload {
+    google.protobuf.Empty query_state = 1;
+    unseal.Request        unseal      = 2;
+    bootstrap.Request     bootstrap   = 3;
+    rekey.Request         rekey       = 4;
+  }
+}
+
+message Response {
+  oneof payload {
+    arbiter.shared.VaultState state     = 1;
+    unseal.Response           unseal    = 2;
+    bootstrap.Response        bootstrap = 3;
+    rekey.Response            rekey     = 4;
+  }
+}

protobufs/shared/vault.proto

@@ -5,7 +5,8 @@ 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;
+  VAULT_STATE_BOOSTRAPPING = 2;
+  VAULT_STATE_SEALED = 3;
+  VAULT_STATE_UNSEALED = 4;
+  VAULT_STATE_ERROR = 5;
 }

protobufs/user_agent.proto

@@ -1,28 +0,0 @@
-syntax = "proto3";
-
-package arbiter.user_agent;
-
-import "user_agent/auth.proto";
-import "user_agent/evm.proto";
-import "user_agent/sdk_client.proto";
-import "user_agent/vault/vault.proto";
-
-message UserAgentRequest {
-  int32 id = 16;
-  oneof payload {
-    auth.Request auth = 1;
-    vault.Request vault = 2;
-    evm.Request evm = 3;
-    sdk_client.Request sdk_client = 4;
-  }
-}
-
-message UserAgentResponse {
-  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/user_agent/vault/bootstrap.proto

@@ -1,24 +0,0 @@
-syntax = "proto3";
-
-package arbiter.user_agent.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/user_agent/vault/vault.proto

@@ -1,24 +0,0 @@
-syntax = "proto3";
-
-package arbiter.user_agent.vault;
-
-import "google/protobuf/empty.proto";
-import "shared/vault.proto";
-import "user_agent/vault/bootstrap.proto";
-import "user_agent/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;
-  }
-}

server/.cargo/config.toml

@@ -0,0 +1,2 @@
+[env]
+MACOSX_DEPLOYMENT_TARGET = "26.3"

server/Cargo.toml

@@ -6,31 +6,29 @@ resolver = "3"
 
 
 [workspace.dependencies]
-alloy = "1.7.3"
+alloy = "2.0.4"
 async-trait = "0.1.89"
 base64 = "0.22.1"
 chrono = { version = "0.4.44", features = ["serde"] }
-ed25519-dalek = { version = "3.0.0-pre.6", features = ["rand_core"] }
 futures = "0.3.32"
-hmac = "0.12.1"
 k256 = { version = "0.13.4", features = ["ecdsa", "pkcs8"] }
-kameo = { version = "0.20.0", git = "https://github.com/tqwewe/kameo" } # hold this until new patch version is released
+kameo = {git = "https://github.com/hdbg/kameo.git", rev = "3e18ba2"}
+kameo_actors = {git = "https://github.com/hdbg/kameo.git", rev = "3e18ba2"}
+hmac = "0.13.0"
 miette = { version = "7.6.0", features = ["fancy", "serde"] }
-ml-dsa = { version = "0.1.0-rc.8", features = ["zeroize"] }
+ml-dsa = { version = "0.1.0-rc.9", features = ["zeroize"] }
 mutants = "0.0.4"
 prost = "0.14.3"
 prost-types = { version = "0.14.3", features = ["chrono"] }
-rand = "0.10.0"
+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 = "0.23.37", features = ["aws-lc-rs", "logging", "prefer-post-quantum", "std"], default-features = false }
-rustls-pki-types = "1.14.0"
-sha2 = "0.10"
+rustls = { version = "0.23.40", features = ["aws-lc-rs", "logging", "prefer-post-quantum", "std"], default-features = false }
+rustls-pki-types = "1.14.1"
+sha2 = "0.11"
 smlang = "0.8.0"
-spki = "0.7"
 thiserror = "2.0.18"
-tokio = { version = "1.50.0", features = ["full"] }
+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"
@@ -64,7 +62,6 @@ unit_bindings = "warn"
 
 # missing_docs = "warn" # ENABLE BY THE FIRST MAJOR VERSION!!
 unnameable_types = "warn"
-variant_size_differences = "warn"
 
 [workspace.lints.clippy]
 derive_partial_eq_without_eq = "allow" 
@@ -98,7 +95,6 @@ doc_include_without_cfg = "warn"
 empty_drop = "warn"
 empty_enum_variants_with_brackets = "warn"
 empty_structs_with_brackets = "warn"
-error_impl_error = "warn"
 exit = "warn"
 filetype_is_file = "warn"
 float_arithmetic = "warn"
@@ -110,7 +106,6 @@ 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"
@@ -170,3 +165,5 @@ 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

@@ -26,3 +26,5 @@ trait-assoc-item-kinds-order = [
     "type",
     "fn",
 ] # community tested standard
+
+too-many-lines-threshold = 150

server/crates/arbiter-client/Cargo.toml

@@ -21,6 +21,9 @@ tokio.workspace = true
 tokio-stream.workspace = true
 thiserror.workspace = true
 http = "1.4.0"
-rustls-webpki = { version = "0.103.10", features = ["aws-lc-rs"] }
+rustls-webpki = { version = "0.103.13", features = ["aws-lc-rs"] }
 async-trait.workspace = true
-rand.workspace = true
+chrono.workspace = true
+
+[lib]
+doctest = false

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

@@ -1,4 +1,8 @@
-use arbiter_crypto::authn::{CLIENT_CONTEXT, SigningKey, format_challenge};
+use crate::{
+    storage::StorageError,
+    transport::{ClientTransport, next_request_id},
+};
+use arbiter_crypto::authn::{self, CLIENT_CONTEXT, SigningKey};
 use arbiter_proto::{
     ClientMetadata,
     proto::{
@@ -16,21 +20,19 @@ use arbiter_proto::{
     },
 };
 
-use crate::{
-    storage::StorageError,
-    transport::{ClientTransport, next_request_id},
-};
+use chrono::DateTime;
 
 #[derive(Debug, thiserror::Error)]
 pub enum AuthError {
-    #[error("Client approval denied by User Agent")]
+    #[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 User Agents online to approve client")]
-    NoUserAgentsOnline,
+    #[error("No Operators online to approve client")]
+    NoOperatorsOnline,
 
     #[error("Signing key storage error")]
     Storage(#[from] StorageError),
@@ -42,7 +44,7 @@ pub enum AuthError {
 fn map_auth_result(code: i32) -> AuthError {
     match AuthResult::try_from(code).unwrap_or(AuthResult::Unspecified) {
         AuthResult::ApprovalDenied => AuthError::ApprovalDenied,
-        AuthResult::NoUserAgentsOnline => AuthError::NoUserAgentsOnline,
+        AuthResult::NoOperatorsOnline => AuthError::NoOperatorsOnline,
         AuthResult::Unspecified
         | AuthResult::Success
         | AuthResult::InvalidKey
@@ -98,7 +100,15 @@ async fn send_auth_challenge_solution(
     key: &SigningKey,
     challenge: AuthChallenge,
 ) -> Result<(), AuthError> {
-    let challenge_payload = format_challenge(challenge.nonce, &challenge.pubkey);
+    let timestamp = DateTime::from_timestamp_nanos(challenge.timestamp_nanos as i64);
+    let challenge = authn::AuthChallenge {
+        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)?

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

@@ -1,8 +1,8 @@
-use std::io::{self, Write};
-
 use arbiter_client::ArbiterClient;
 use arbiter_proto::{ClientMetadata, url::ArbiterUrl};
 
+use std::io::{self, Write};
+
 #[tokio::main]
 async fn main() {
     println!("Testing connection to Arbiter server...");

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

@@ -1,21 +1,20 @@
-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;
-
+#[cfg(feature = "evm")]
+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,
+};
 
-#[cfg(feature = "evm")]
-use crate::wallets::evm::ArbiterEvmWallet;
+use std::sync::Arc;
+use tokio::sync::{Mutex, mpsc};
+use tokio_stream::wrappers::ReceiverStream;
+use tonic::transport::ClientTlsConfig;
 
 #[derive(Debug, thiserror::Error)]
 pub enum ArbiterClientError {

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

@@ -1,5 +1,6 @@
 use arbiter_crypto::authn::SigningKey;
 use arbiter_proto::home_path;
+
 use std::path::{Path, PathBuf};
 
 #[derive(Debug, thiserror::Error)]

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

@@ -1,4 +1,5 @@
 use arbiter_proto::proto::client::{ClientRequest, ClientResponse};
+
 use std::sync::atomic::{AtomicI32, Ordering};
 use tokio::sync::mpsc;
 
@@ -24,10 +25,7 @@ pub struct ClientTransport {
 }
 
 impl ClientTransport {
-    pub(crate) async fn send(
-        &mut self,
-        request: ClientRequest,
-    ) -> Result<(), ClientSignError> {
+    pub(crate) async fn send(&mut self, request: ClientRequest) -> Result<(), ClientSignError> {
         self.sender
             .send(request)
             .await

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

@@ -1,13 +1,4 @@
-use alloy::{
-    consensus::SignableTransaction,
-    network::TxSigner,
-    primitives::{Address, B256, ChainId, Signature},
-    signers::{Error, Result, Signer},
-};
-use async_trait::async_trait;
-use std::sync::Arc;
-use tokio::sync::Mutex;
-
+use crate::transport::{ClientTransport, next_request_id};
 use arbiter_proto::proto::{
     client::{
         ClientRequest,
@@ -25,7 +16,15 @@ use arbiter_proto::proto::{
     shared::evm::TransactionEvalError,
 };
 
-use crate::transport::{ClientTransport, next_request_id};
+use alloy::{
+    consensus::SignableTransaction,
+    network::TxSigner,
+    primitives::{Address, B256, ChainId, Signature},
+    signers::{Error, Result, Signer},
+};
+use async_trait::async_trait;
+use std::sync::Arc;
+use tokio::sync::Mutex;
 
 /// A typed error payload returned by [`ArbiterEvmWallet`] transaction signing.
 ///

server/crates/arbiter-crypto/Cargo.toml

@@ -6,16 +6,20 @@ edition = "2024"
 [dependencies]
 ml-dsa = {workspace = true, optional = true }
 rand = {workspace = true, optional = true}
-base64 = {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", "dep:base64"]
+authn = ["dep:ml-dsa", "dep:rand"]
 safecell = ["dep:memsafe"]
+
+[lib]
+doctest = false

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

@@ -1,16 +1,66 @@
-use base64::{Engine as _, prelude::BASE64_STANDARD};
+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 USERAGENT_CONTEXT: &[u8] = b"arbiter_user_agent";
+pub static OPERATOR_CONTEXT: &[u8] = b"arbiter_operator";
+pub static GOVERNANCE_CONTEXT: &[u8] = b"arbiter_governance_vote";
 
-pub fn format_challenge(nonce: i32, pubkey: &[u8]) -> Vec<u8> {
-    let concat_form = format!("{}:{}", nonce, BASE64_STANDARD.encode(pubkey));
-    concat_form.into_bytes()
+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;
@@ -36,12 +86,15 @@ impl PublicKey {
     }
 
     #[must_use]
-    pub fn verify(&self, nonce: i32, context: &[u8], signature: &Signature) -> bool {
-        self.0.verify_with_context(
-            &format_challenge(nonce, &self.to_bytes()),
-            context,
-            &signature.0,
-        )
+    pub fn verify(&self, challenge: &AuthChallenge, context: &[u8], signature: &Signature) -> bool {
+        let challenge = challenge.format();
+        self.0
+            .verify_with_context(&challenge, context, &signature.0)
+    }
+
+    #[must_use]
+    pub fn verify_message(&self, message: &[u8], context: &[u8], signature: &Signature) -> bool {
+        self.0.verify_with_context(message, context, &signature.0)
     }
 }
 
@@ -75,11 +128,14 @@ impl SigningKey {
             .map(Into::into)
     }
 
-    pub fn sign_challenge(&self, nonce: i32, context: &[u8]) -> Result<Signature, Error> {
-        self.sign_message(
-            &format_challenge(nonce, &self.public_key().to_bytes()),
-            context,
-        )
+    pub fn sign_challenge(
+        &self,
+        challenge: &AuthChallenge,
+        context: &[u8],
+    ) -> Result<Signature, Error> {
+        let challenge = challenge.format();
+
+        self.sign_message(&challenge, context)
     }
 }
 
@@ -140,7 +196,9 @@ impl TryFrom<&'_ [u8]> for Signature {
 mod tests {
     use ml_dsa::{KeyGen, MlDsa87, signature::Keypair as _};
 
-    use super::{CLIENT_CONTEXT, PublicKey, Signature, SigningKey, USERAGENT_CONTEXT};
+    use crate::authn::AuthChallenge;
+
+    use super::{CLIENT_CONTEXT, PublicKey, Signature, SigningKey, OPERATOR_CONTEXT};
 
     #[test]
     fn public_key_round_trip_decodes() {
@@ -169,13 +227,13 @@ mod tests {
     fn challenge_verification_uses_context_and_canonical_key_bytes() {
         let key = SigningKey::generate();
         let public_key = key.public_key();
-        let nonce = 17;
+        let challenge = AuthChallenge::generate(&mut rand::rng());
         let signature = key
-            .sign_challenge(nonce, CLIENT_CONTEXT)
+            .sign_challenge(&challenge, CLIENT_CONTEXT)
             .expect("signature should be created");
 
-        assert!(public_key.verify(nonce, CLIENT_CONTEXT, &signature));
-        assert!(!public_key.verify(nonce, USERAGENT_CONTEXT, &signature));
+        assert!(public_key.verify(&challenge, CLIENT_CONTEXT, &signature));
+        assert!(!public_key.verify(&challenge, OPERATOR_CONTEXT, &signature));
     }
 
     #[test]
@@ -185,10 +243,16 @@ mod tests {
 
         assert_eq!(restored.public_key(), original.public_key());
 
+        let challenge = AuthChallenge::generate(&mut rand::rng());
+
         let signature = restored
-            .sign_challenge(9, CLIENT_CONTEXT)
+            .sign_challenge(&challenge, CLIENT_CONTEXT)
             .expect("signature should be created");
 
-        assert!(restored.public_key().verify(9, CLIENT_CONTEXT, &signature));
+        assert!(
+            restored
+                .public_key()
+                .verify(&challenge, CLIENT_CONTEXT, &signature)
+        );
     }
 }

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

@@ -1,6 +1,7 @@
-pub use hmac::digest::Digest;
 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",

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

@@ -3,3 +3,5 @@ pub mod authn;
 pub mod hashing;
 #[cfg(feature = "safecell")]
 pub mod safecell;
+
+pub use x_wing;

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

@@ -1,7 +1,9 @@
-use std::ops::{Deref, DerefMut};
-use std::{any::type_name, fmt};
-
 use memsafe::MemSafe;
+use std::{
+    any::type_name,
+    fmt,
+    ops::{Deref, DerefMut},
+};
 
 pub trait SafeCellHandle<T> {
     type CellRead<'a>: Deref<Target = T>
@@ -20,7 +22,7 @@ pub trait SafeCellHandle<T> {
     fn read(&mut self) -> Self::CellRead<'_>;
     fn write(&mut self) -> Self::CellWrite<'_>;
 
-    fn new_inline<F>(f: F) -> Self
+    fn new_inline_default<F>(f: F) -> Self
     where
         Self: Sized,
         T: Default,
@@ -34,6 +36,14 @@ pub trait SafeCellHandle<T> {
         cell
     }
 
+    fn new_inline<F>(f: Box<F>) -> Self
+    where
+        Self: Sized,
+        F: for<'a> FnOnce() -> T,
+    {
+        Self::new(f())
+    }
+
     #[inline(always)]
     fn read_inline<F, R>(&mut self, f: F) -> R
     where

server/crates/arbiter-macros/Cargo.toml

@@ -5,6 +5,7 @@ edition = "2024"
 
 [lib]
 proc-macro = true
+doctest = false
 
 [dependencies]
 proc-macro2 = "1.0"

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

@@ -1,10 +1,8 @@
+use crate::utils::{HASHABLE_TRAIT_PATH, HMAC_DIGEST_PATH};
+
 use proc_macro2::{Span, TokenStream, TokenTree};
 use quote::quote;
-use syn::parse_quote;
-use syn::spanned::Spanned;
-use syn::{DataStruct, DeriveInput, Fields, Generics, Index};
-
-use crate::utils::{HASHABLE_TRAIT_PATH, HMAC_DIGEST_PATH};
+use syn::{DataStruct, DeriveInput, Fields, Generics, Index, parse_quote, spanned::Spanned};
 
 pub(crate) fn derive(input: &DeriveInput) -> TokenStream {
     match &input.data {

server/crates/arbiter-proto/Cargo.toml

@@ -9,7 +9,6 @@ license = "Apache-2.0"
 tonic.workspace = true
 tokio.workspace = true
 futures.workspace = true
-hex = "0.4.3"
 tonic-prost = "0.14.5"
 prost.workspace = true
 kameo.workspace = true
@@ -19,18 +18,18 @@ thiserror.workspace = true
 rustls-pki-types.workspace = true
 base64.workspace = true
 prost-types.workspace = true
-tracing.workspace = true
 async-trait.workspace = true
 tokio-stream.workspace = true
 
 [build-dependencies]
 tonic-prost-build = "0.14.5"
-protoc-bin-vendored = "3"
 
 [dev-dependencies]
 rstest.workspace = true
-rand.workspace = true
 rcgen.workspace = true
 
+[lib]
+doctest = false
+
 [package.metadata.cargo-shear]
-ignored = ["tonic-prost", "prost", "kameo"]
+ignored = ["tonic-prost", "prost"]

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!("{}/user_agent.proto", PROTOBUF_DIR),
+                format!("{}/operator.proto", PROTOBUF_DIR),
                 format!("{}/client.proto", PROTOBUF_DIR),
                 format!("{}/evm.proto", PROTOBUF_DIR),
             ],

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

@@ -12,30 +12,38 @@ pub mod proto {
         }
     }
 
-    pub mod user_agent {
-        tonic::include_proto!("arbiter.user_agent");
+    pub mod operator {
+        tonic::include_proto!("arbiter.operator");
 
         pub mod auth {
-            tonic::include_proto!("arbiter.user_agent.auth");
+            tonic::include_proto!("arbiter.operator.auth");
         }
 
         pub mod evm {
-            tonic::include_proto!("arbiter.user_agent.evm");
+            tonic::include_proto!("arbiter.operator.evm");
+        }
+
+        pub mod governance {
+            tonic::include_proto!("arbiter.operator.governance");
         }
 
         pub mod sdk_client {
-            tonic::include_proto!("arbiter.user_agent.sdk_client");
+            tonic::include_proto!("arbiter.operator.sdk_client");
         }
 
         pub mod vault {
-            tonic::include_proto!("arbiter.user_agent.vault");
+            tonic::include_proto!("arbiter.operator.vault");
 
             pub mod bootstrap {
-                tonic::include_proto!("arbiter.user_agent.vault.bootstrap");
+                tonic::include_proto!("arbiter.operator.vault.bootstrap");
+            }
+
+            pub mod rekey {
+                tonic::include_proto!("arbiter.operator.vault.rekey");
             }
 
             pub mod unseal {
-                tonic::include_proto!("arbiter.user_agent.vault.unseal");
+                tonic::include_proto!("arbiter.operator.vault.unseal");
             }
         }
     }

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

@@ -54,10 +54,9 @@
 //!   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 std::marker::PhantomData;
-
 use async_trait::async_trait;
+use kameo::{error::Infallible, prelude::*};
+use std::marker::PhantomData;
 
 /// Errors returned by transport adapters implementing [`Bi`].
 #[derive(thiserror::Error, Debug)]
@@ -106,6 +105,36 @@ 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>;
@@ -161,3 +190,29 @@ 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

@@ -1,7 +1,6 @@
-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";

server/crates/arbiter-server/Cargo.toml

@@ -9,8 +9,8 @@ license = "Apache-2.0"
 workspace = true
 
 [dependencies]
-diesel = { version = "2.3.7", features = ["chrono", "returning_clauses_for_sqlite_3_35", "serde_json", "time", "uuid"] }
-diesel-async = { version = "0.8.0", features = [
+diesel = { version = "2.3.9", features = ["chrono", "returning_clauses_for_sqlite_3_35", "serde_json", "time", "uuid"] }
+diesel-async = { version = "0.9.0", features = [
     "bb8",
     "migrations",
     "sqlite",
@@ -27,17 +27,12 @@ tokio.workspace = true
 rustls.workspace = true
 smlang.workspace = true
 thiserror.workspace = true
-fatality = "0.1.1"
-diesel_migrations = { version = "2.3.1", features = ["sqlite"] }
+diesel_migrations = { version = "2.3.2", features = ["sqlite"] }
 async-trait.workspace = true
-secrecy = "0.10.3"
-futures.workspace = true
 tokio-stream.workspace = true
-dashmap = "6.1.0"
 rand.workspace = true
 rcgen.workspace = true
 chrono.workspace = true
-zeroize = { version = "1.8.2", features = ["std", "simd"] }
 kameo.workspace = true
 chacha20poly1305 = { version = "0.10.1", features = ["std"] }
 argon2 = { version = "0.5.3", features = ["zeroize"] }
@@ -46,22 +41,24 @@ strum = { version = "0.28.0", features = ["derive"] }
 pem = "3.0.6"
 sha2.workspace = true
 hmac.workspace = true
-spki.workspace = true
 alloy.workspace = true
-prost-types.workspace = true
 prost.workspace = true
+prost-types.workspace = true
 arbiter-tokens-registry.path = "../arbiter-tokens-registry"
 anyhow = "1.0.102"
-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
+vsss-rs = "5.4.0"
+rand_core = "0.6"
 
 [dev-dependencies]
-insta = "1.46.3"
 proptest = "1.11.0"
 rstest.workspace = true
 test-log = { version = "0.2", default-features = false, features = ["trace"] }
+ml-dsa.workspace = true
+
+[lib]
+doctest = false

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

@@ -43,15 +43,25 @@ 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 useragent_client (
+create table if not exists operator_identity (
     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),
     created_at integer not null default(unixepoch ('now')),
     updated_at integer not null default(unixepoch ('now'))
 ) STRICT;
-create unique index if not exists uniq_useragent_client_public_key on useragent_client (public_key, key_type);
+create unique index if not exists uniq_operator_identity_public_key on operator_identity (public_key);
+
+create table if not exists operator (
+    id integer primary key references operator_identity(id) on delete restrict, -- same id as operator_identity
+
+    share blob not null,
+    share_nonce blob not null,
+    share_salt blob not null default (randomblob(32)),
+
+    created_at integer not null default(unixepoch ('now')),
+    updated_at integer not null default(unixepoch ('now'))
+
+) STRICT;
 
 create table if not exists client_metadata (
     id integer not null primary key,
@@ -73,7 +83,6 @@ 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')),
@@ -207,3 +216,73 @@ create table if not exists integrity_envelope (
 ) STRICT;
 
 create unique index if not exists uniq_integrity_envelope_entity on integrity_envelope (entity_kind, entity_id);
+
+create table if not exists proposal (
+    id           integer not null primary key,
+    kind         text    not null,
+    payload      blob    not null,
+    initiator_id integer not null references operator_identity(id) on delete restrict,
+    created_at   integer not null default(unixepoch('now')),
+    expires_at   integer not null,
+    status       text    not null default 'pending'
+        check (status in ('pending', 'approved', 'rejected', 'expired'))
+) STRICT;
+
+create table if not exists proposal_vote (
+    id          integer not null primary key,
+    proposal_id integer not null references proposal(id) on delete cascade,
+    operator_id integer not null references operator_identity(id) on delete restrict,
+    approve     integer not null check (approve in (0, 1)),
+    signature   blob    not null,
+    voted_at    integer not null default(unixepoch('now')),
+    unique (proposal_id, operator_id)
+) STRICT;
+
+
+create table if not exists proposal_result (
+    proposal_id integer not null primary key references proposal(id) on delete cascade,
+    data        blob    not null,
+    created_at  integer not null default(unixepoch('now'))
+) STRICT;
+
+-- ===============================
+-- Recovery Operators (§3.4/§3.5/§3.6)
+-- ===============================
+
+-- Encrypted Shamir shares for recovery operators (mirrors the `operator` table).
+create table if not exists recovery_operator (
+    id          integer not null primary key references recovery_operator_identity(id) on delete restrict,
+    share       blob    not null,
+    share_nonce blob    not null,
+    share_salt  blob    not null,
+    created_at  integer not null default(unixepoch('now')),
+    updated_at  integer not null default(unixepoch('now'))
+) STRICT;
+
+create table if not exists recovery_operator_identity (
+    id         integer not null primary key,
+    public_key blob    not null unique,
+    created_at integer not null default(unixepoch('now')),
+    updated_at integer not null default(unixepoch('now'))
+) STRICT;
+
+-- One active wakeup request at a time. A request is pending when cancelled_at IS NULL
+-- and requested_at + 14 days > now. It becomes active (recovery live) after 14 days.
+create table if not exists recovery_wakeup_request (
+    id           integer not null primary key,
+    requested_by integer not null references operator_identity(id) on delete restrict,
+    requested_at integer not null default(unixepoch('now')),
+    cancelled_by integer references operator_identity(id) on delete restrict,
+    cancelled_at integer
+) STRICT;
+
+-- Votes cast by recovery operators; only allowed on replace_operator proposals.
+create table if not exists recovery_proposal_vote (
+    id                   integer not null primary key,
+    proposal_id          integer not null references proposal(id) on delete cascade,
+    recovery_operator_id integer not null references recovery_operator_identity(id) on delete restrict,
+    approve              integer not null check (approve in (0, 1)),
+    signature            blob    not null,
+    voted_at             integer not null default(unixepoch('now')),
+    unique (proposal_id, recovery_operator_id)
+) STRICT;

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

@@ -1,13 +1,13 @@
+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 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> {
@@ -27,7 +27,7 @@ pub async fn generate_token() -> Result<String, std::io::Error> {
 }
 
 #[derive(Error, Debug)]
-pub enum BootstrappError {
+pub enum Error {
     #[error("Database error: {0}")]
     Database(#[from] db::PoolError),
 
@@ -44,11 +44,11 @@ pub struct Bootstrapper {
 }
 
 impl Bootstrapper {
-    pub async fn new(db: &DatabasePool) -> Result<Self, BootstrappError> {
+    pub async fn new(db: &DatabasePool) -> Result<Self, Error> {
         let row_count: i64 = {
             let mut conn = db.get().await?;
 
-            schema::useragent_client::table
+            schema::operator::table
                 .count()
                 .get_result(&mut conn)
                 .await?

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

@@ -1,462 +0,0 @@
-use arbiter_crypto::authn::{self, CLIENT_CONTEXT};
-use arbiter_proto::{
-    ClientMetadata,
-    proto::client::auth::{AuthChallenge as ProtoAuthChallenge, AuthResult as ProtoAuthResult},
-    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 tracing::error;
-
-use crate::{
-    actors::{
-        client::{ClientConnection, ClientCredentials, ClientProfile},
-        flow_coordinator::{self, RequestClientApproval},
-        keyholder::KeyHolder,
-    },
-    crypto::integrity::{self, AttestationStatus},
-    db::{
-        self,
-        models::{ProgramClientMetadata, SqliteTimestamp},
-        schema::program_client,
-    },
-};
-
-#[derive(thiserror::Error, Debug, Clone, PartialEq, Eq)]
-pub enum ClientAuthError {
-    #[error("Client approval request failed")]
-    ApproveError(#[from] ApproveError),
-
-    #[error("Database operation failed")]
-    DatabaseOperationFailed,
-
-    #[error("Database pool unavailable")]
-    DatabasePoolUnavailable,
-
-    #[error("Integrity check failed")]
-    IntegrityCheckFailed,
-
-    #[error("Invalid challenge solution")]
-    InvalidChallengeSolution,
-
-    #[error("Transport error")]
-    Transport,
-}
-
-impl From<diesel::result::Error> for ClientAuthError {
-    fn from(e: diesel::result::Error) -> Self {
-        error!(?e, "Database error");
-        Self::DatabaseOperationFailed
-    }
-}
-
-impl From<ClientAuthError> for arbiter_proto::proto::client::auth::AuthResult {
-    fn from(value: ClientAuthError) -> Self {
-        match value {
-            ClientAuthError::ApproveError(e) => match e {
-                ApproveError::Denied => Self::ApprovalDenied,
-                ApproveError::Internal => Self::Internal,
-                ApproveError::Upstream(flow_coordinator::ApprovalError::NoUserAgentsConnected) => {
-                    Self::NoUserAgentsOnline
-                } // ApproveError::Upstream(_) => Self::Internal,
-            },
-            ClientAuthError::DatabaseOperationFailed
-            | ClientAuthError::DatabasePoolUnavailable
-            | ClientAuthError::IntegrityCheckFailed
-            | ClientAuthError::Transport => Self::Internal,
-            ClientAuthError::InvalidChallengeSolution => Self::InvalidSignature,
-        }
-    }
-}
-
-#[derive(thiserror::Error, Debug, Clone, PartialEq, Eq)]
-pub enum ApproveError {
-    #[error("Client connection denied by user agents")]
-    Denied,
-
-    #[error("Internal error")]
-    Internal,
-
-    #[error("Upstream error: {0}")]
-    Upstream(flow_coordinator::ApprovalError),
-}
-
-#[derive(Debug, Clone)]
-pub enum Inbound {
-    AuthChallengeRequest {
-        pubkey: authn::PublicKey,
-        metadata: ClientMetadata,
-    },
-    AuthChallengeSolution {
-        signature: authn::Signature,
-    },
-}
-
-#[derive(Debug, Clone)]
-pub enum Outbound {
-    AuthChallenge {
-        pubkey: authn::PublicKey,
-        nonce: i32,
-    },
-    AuthSuccess,
-}
-
-impl From<Outbound> for arbiter_proto::proto::client::auth::response::Payload {
-    fn from(value: Outbound) -> Self {
-        match value {
-            Outbound::AuthChallenge { pubkey, nonce } => Self::Challenge(ProtoAuthChallenge {
-                pubkey: pubkey.to_bytes(),
-                nonce,
-            }),
-            Outbound::AuthSuccess => Self::Result(ProtoAuthResult::Success.into()),
-        }
-    }
-}
-
-/// Returns the current nonce and client ID for a registered client.
-/// Returns `None` if the pubkey is not registered.
-async fn get_current_nonce_and_id(
-    db: &db::DatabasePool,
-    pubkey: &authn::PublicKey,
-) -> Result<Option<(i32, i32)>, ClientAuthError> {
-    let pubkey_bytes = pubkey.to_bytes();
-    let mut conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        ClientAuthError::DatabasePoolUnavailable
-    })?;
-    program_client::table
-        .filter(program_client::public_key.eq(&pubkey_bytes))
-        .select((program_client::id, program_client::nonce))
-        .first::<(i32, i32)>(&mut conn)
-        .await
-        .optional()
-        .map_err(|e| {
-            error!(error = ?e, "Database error");
-            ClientAuthError::DatabaseOperationFailed
-        })
-}
-
-async fn verify_integrity(
-    db: &db::DatabasePool,
-    keyholder: &ActorRef<KeyHolder>,
-    pubkey: &authn::PublicKey,
-) -> Result<(), ClientAuthError> {
-    let mut db_conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        ClientAuthError::DatabasePoolUnavailable
-    })?;
-
-    let (id, nonce) = get_current_nonce_and_id(db, pubkey).await?.ok_or_else(|| {
-        error!("Client not found during integrity verification");
-        ClientAuthError::DatabaseOperationFailed
-    })?;
-
-    let attestation = integrity::verify_entity(
-        &mut db_conn,
-        keyholder,
-        &ClientCredentials {
-            pubkey: pubkey.clone(),
-            nonce,
-        },
-        id,
-    )
-    .await
-    .map_err(|e| {
-        error!(?e, "Integrity verification failed");
-        ClientAuthError::IntegrityCheckFailed
-    })?;
-
-    if attestation != AttestationStatus::Attested {
-        error!("Integrity attestation unavailable for client {id}");
-        return Err(ClientAuthError::IntegrityCheckFailed);
-    }
-
-    Ok(())
-}
-
-/// Atomically increments the nonce and re-signs the integrity envelope.
-/// Returns the new nonce, which is used as the challenge nonce.
-async fn create_nonce(
-    db: &db::DatabasePool,
-    keyholder: &ActorRef<KeyHolder>,
-    pubkey: &authn::PublicKey,
-) -> Result<i32, ClientAuthError> {
-    let pubkey_bytes = pubkey.to_bytes();
-    let pubkey = pubkey.clone();
-
-    let mut conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        ClientAuthError::DatabasePoolUnavailable
-    })?;
-
-    conn.exclusive_transaction(|conn| {
-        let keyholder = keyholder.clone();
-        let pubkey = pubkey.clone();
-        Box::pin(async move {
-            let (id, new_nonce): (i32, i32) = update(program_client::table)
-                .filter(program_client::public_key.eq(&pubkey_bytes))
-                .set(program_client::nonce.eq(program_client::nonce + 1))
-                .returning((program_client::id, program_client::nonce))
-                .get_result(conn)
-                .await?;
-
-            integrity::sign_entity(
-                conn,
-                &keyholder,
-                &ClientCredentials {
-                    pubkey: pubkey.clone(),
-                    nonce: new_nonce,
-                },
-                id,
-            )
-            .await
-            .map_err(|e| {
-                error!(?e, "Integrity sign failed after nonce update");
-                ClientAuthError::DatabaseOperationFailed
-            })?;
-
-            Ok(new_nonce)
-        })
-    })
-    .await
-}
-
-async fn approve_new_client(
-    actors: &crate::actors::GlobalActors,
-    profile: ClientProfile,
-) -> Result<(), ClientAuthError> {
-    let result = actors
-        .flow_coordinator
-        .ask(RequestClientApproval { client: profile })
-        .await;
-
-    match result {
-        Ok(true) => Ok(()),
-        Ok(false) => Err(ClientAuthError::ApproveError(ApproveError::Denied)),
-        Err(SendError::HandlerError(e)) => {
-            error!(error = ?e, "Approval upstream error");
-            Err(ClientAuthError::ApproveError(ApproveError::Upstream(e)))
-        }
-        Err(e) => {
-            error!(error = ?e, "Approval request to flow coordinator failed");
-            Err(ClientAuthError::ApproveError(ApproveError::Internal))
-        }
-    }
-}
-
-async fn insert_client(
-    db: &db::DatabasePool,
-    keyholder: &ActorRef<KeyHolder>,
-    pubkey: &authn::PublicKey,
-    metadata: &ClientMetadata,
-) -> Result<i32, ClientAuthError> {
-    use crate::db::schema::client_metadata;
-    let pubkey = pubkey.clone();
-    let metadata = metadata.clone();
-
-    let mut conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        ClientAuthError::DatabasePoolUnavailable
-    })?;
-
-    conn.exclusive_transaction(|conn| {
-        let keyholder = keyholder.clone();
-        let pubkey = pubkey.clone();
-        Box::pin(async move {
-            const NONCE_START: i32 = 1;
-
-            let metadata_id = insert_into(client_metadata::table)
-                .values((
-                    client_metadata::name.eq(&metadata.name),
-                    client_metadata::description.eq(&metadata.description),
-                    client_metadata::version.eq(&metadata.version),
-                ))
-                .returning(client_metadata::id)
-                .get_result::<i32>(conn)
-                .await?;
-
-            let client_id = insert_into(program_client::table)
-                .values((
-                    program_client::public_key.eq(pubkey.to_bytes()),
-                    program_client::metadata_id.eq(metadata_id),
-                    program_client::nonce.eq(NONCE_START),
-                ))
-                .on_conflict_do_nothing()
-                .returning(program_client::id)
-                .get_result::<i32>(conn)
-                .await?;
-
-            integrity::sign_entity(
-                conn,
-                &keyholder,
-                &ClientCredentials {
-                    pubkey: pubkey.clone(),
-                    nonce: NONCE_START,
-                },
-                client_id,
-            )
-            .await
-            .map_err(|e| {
-                error!(error = ?e, "Failed to sign integrity tag for new client key");
-                ClientAuthError::DatabaseOperationFailed
-            })?;
-
-            Ok(client_id)
-        })
-    })
-    .await
-}
-
-async fn sync_client_metadata(
-    db: &db::DatabasePool,
-    client_id: i32,
-    metadata: &ClientMetadata,
-) -> Result<(), ClientAuthError> {
-    use crate::db::schema::{client_metadata, client_metadata_history};
-
-    let now = SqliteTimestamp(Utc::now());
-
-    let mut conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        ClientAuthError::DatabasePoolUnavailable
-    })?;
-
-    conn.exclusive_transaction(|conn| {
-        let metadata = metadata.clone();
-        Box::pin(async move {
-            let (current_metadata_id, current): (i32, ProgramClientMetadata) =
-                program_client::table
-                    .find(client_id)
-                    .inner_join(client_metadata::table)
-                    .select((
-                        program_client::metadata_id,
-                        ProgramClientMetadata::as_select(),
-                    ))
-                    .first(conn)
-                    .await?;
-
-            let unchanged = current.name == metadata.name
-                && current.description == metadata.description
-                && current.version == metadata.version;
-            if unchanged {
-                return Ok(());
-            }
-
-            insert_into(client_metadata_history::table)
-                .values((
-                    client_metadata_history::metadata_id.eq(current_metadata_id),
-                    client_metadata_history::client_id.eq(client_id),
-                ))
-                .execute(conn)
-                .await?;
-
-            let metadata_id = insert_into(client_metadata::table)
-                .values((
-                    client_metadata::name.eq(&metadata.name),
-                    client_metadata::description.eq(&metadata.description),
-                    client_metadata::version.eq(&metadata.version),
-                ))
-                .returning(client_metadata::id)
-                .get_result::<i32>(conn)
-                .await?;
-
-            update(program_client::table.find(client_id))
-                .set((
-                    program_client::metadata_id.eq(metadata_id),
-                    program_client::updated_at.eq(now),
-                ))
-                .execute(conn)
-                .await?;
-
-            Ok::<(), diesel::result::Error>(())
-        })
-    })
-    .await
-    .map_err(|e| {
-        error!(error = ?e, "Database error");
-        ClientAuthError::DatabaseOperationFailed
-    })
-}
-
-async fn challenge_client<T>(
-    transport: &mut T,
-    pubkey: authn::PublicKey,
-    nonce: i32,
-) -> Result<(), ClientAuthError>
-where
-    T: Bi<Inbound, Result<Outbound, ClientAuthError>> + ?Sized,
-{
-    transport
-        .send(Ok(Outbound::AuthChallenge {
-            pubkey: pubkey.clone(),
-            nonce,
-        }))
-        .await
-        .map_err(|e| {
-            error!(error = ?e, "Failed to send auth challenge");
-            ClientAuthError::Transport
-        })?;
-
-    let signature = expect_message(transport, |req: Inbound| match req {
-        Inbound::AuthChallengeSolution { signature } => Some(signature),
-        Inbound::AuthChallengeRequest { .. } => None,
-    })
-    .await
-    .map_err(|e| {
-        error!(error = ?e, "Failed to receive challenge solution");
-        ClientAuthError::Transport
-    })?;
-
-    if !pubkey.verify(nonce, CLIENT_CONTEXT, &signature) {
-        error!("Challenge solution verification failed");
-        return Err(ClientAuthError::InvalidChallengeSolution);
-    }
-
-    Ok(())
-}
-
-pub async fn authenticate<T>(
-    props: &mut ClientConnection,
-    transport: &mut T,
-) -> Result<i32, ClientAuthError>
-where
-    T: Bi<Inbound, Result<Outbound, ClientAuthError>> + Send + ?Sized,
-{
-    let Some(Inbound::AuthChallengeRequest { pubkey, metadata }) = transport.recv().await else {
-        return Err(ClientAuthError::Transport);
-    };
-
-    let client_id = if let Some((id, _)) = get_current_nonce_and_id(&props.db, &pubkey).await? {
-        verify_integrity(&props.db, &props.actors.key_holder, &pubkey).await?;
-        id
-    } else {
-        approve_new_client(
-            &props.actors,
-            ClientProfile {
-                pubkey: pubkey.clone(),
-                metadata: metadata.clone(),
-            },
-        )
-        .await?;
-        insert_client(&props.db, &props.actors.key_holder, &pubkey, &metadata).await?
-    };
-
-    sync_client_metadata(&props.db, client_id, &metadata).await?;
-    let challenge_nonce = create_nonce(&props.db, &props.actors.key_holder, &pubkey).await?;
-    challenge_client(transport, pubkey, challenge_nonce).await?;
-
-    transport
-        .send(Ok(Outbound::AuthSuccess))
-        .await
-        .map_err(|e| {
-            error!(error = ?e, "Failed to send auth success");
-            ClientAuthError::Transport
-        })?;
-
-    Ok(client_id)
-}

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

@@ -1,19 +1,9 @@
-use alloy::{
-    consensus::TxEip1559, network::TxSignerSync as _, primitives::Address, signers::Signature,
-};
-use diesel::{
-    ExpressionMethods, OptionalExtension as _, QueryDsl, SelectableHelper as _, dsl::insert_into,
-};
-use diesel_async::RunQueryDsl;
-use kameo::{Actor, actor::ActorRef, messages};
-use rand::{SeedableRng, rng, rngs::StdRng};
-
 use crate::{
-    actors::keyholder::{CreateNew, Decrypt, KeyHolder},
+    actors::vault::{CreateNew, Decrypt, Vault},
     crypto::integrity,
     db::{
         DatabaseError, DatabasePool,
-        models::{self},
+        models::{self, EvmWalletId},
         schema,
     },
     evm::{
@@ -26,6 +16,16 @@ use crate::{
 };
 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,
+};
+use diesel_async::RunQueryDsl;
+use kameo::{Actor, actor::ActorRef, messages};
+use rand::{SeedableRng, rng, rngs::StdRng};
+
 pub use crate::evm::safe_signer;
 
 #[derive(Debug, thiserror::Error)]
@@ -36,11 +36,11 @@ pub enum SignTransactionError {
     #[error("Database error: {0}")]
     Database(#[from] DatabaseError),
 
-    #[error("Keyholder error: {0}")]
-    Keyholder(#[from] crate::actors::keyholder::KeyHolderError),
+    #[error("Vault error: {0}")]
+    Vault(#[from] crate::actors::vault::Error),
 
-    #[error("Keyholder mailbox error")]
-    KeyholderSend,
+    #[error("Vault mailbox error")]
+    VaultSend,
 
     #[error("Signing error: {0}")]
     Signing(#[from] alloy::signers::Error),
@@ -50,36 +50,36 @@ pub enum SignTransactionError {
 }
 
 #[derive(Debug, thiserror::Error)]
-pub enum EvmActorError {
-    #[error("Keyholder error: {0}")]
-    Keyholder(#[from] crate::actors::keyholder::KeyHolderError),
+pub enum Error {
+    #[error("Vault error: {0}")]
+    Vault(#[from] crate::actors::vault::Error),
 
-    #[error("Keyholder mailbox error")]
-    KeyholderSend,
+    #[error("Vault mailbox error")]
+    VaultSend,
 
     #[error("Database error: {0}")]
     Database(#[from] DatabaseError),
 
     #[error("Integrity violation: {0}")]
-    Integrity(#[from] integrity::IntegrityError),
+    Integrity(#[from] integrity::Error),
 }
 
 #[derive(Actor)]
 pub struct EvmActor {
-    pub keyholder: ActorRef<KeyHolder>,
+    pub vault: ActorRef<Vault>,
     pub db: DatabasePool,
     pub rng: StdRng,
     pub engine: evm::Engine,
 }
 
 impl EvmActor {
-    pub fn new(keyholder: ActorRef<KeyHolder>, db: DatabasePool) -> Self {
+    pub fn new(vault: ActorRef<Vault>, 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(), keyholder.clone());
+        let engine = evm::Engine::new(db.clone(), vault.clone());
         Self {
-            keyholder,
+            vault,
             db,
             rng,
             engine,
@@ -90,16 +90,16 @@ impl EvmActor {
 #[messages]
 impl EvmActor {
     #[message]
-    pub async fn generate(&mut self) -> Result<(i32, Address), EvmActorError> {
+    pub async fn generate(&mut self) -> Result<(i32, Address), Error> {
         let (mut key_cell, address) = safe_signer::generate(&mut self.rng);
 
         let plaintext = key_cell.read_inline(|reader| SafeCell::new(reader.to_vec()));
 
         let aead_id: i32 = self
-            .keyholder
+            .vault
             .ask(CreateNew { plaintext })
             .await
-            .map_err(|_| EvmActorError::KeyholderSend)?;
+            .map_err(|_| Error::VaultSend)?;
 
         let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
         let wallet_id = insert_into(schema::evm_wallet::table)
@@ -116,7 +116,7 @@ impl EvmActor {
     }
 
     #[message]
-    pub async fn list_wallets(&self) -> Result<Vec<(i32, Address)>, EvmActorError> {
+    pub async fn list_wallets(&self) -> Result<Vec<(EvmWalletId, Address)>, Error> {
         let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
         let rows: Vec<models::EvmWallet> = schema::evm_wallet::table
             .select(models::EvmWallet::as_select())
@@ -134,11 +134,11 @@ impl EvmActor {
 #[messages]
 impl EvmActor {
     #[message]
-    pub async fn useragent_create_grant(
+    pub async fn operator_create_grant(
         &mut self,
         basic: SharedGrantSettings,
         grant: SpecificGrant,
-    ) -> Result<i32, EvmActorError> {
+    ) -> Result<i32, Error> {
         match grant {
             SpecificGrant::EtherTransfer(settings) => self
                 .engine
@@ -147,7 +147,7 @@ impl EvmActor {
                     specific: settings,
                 })
                 .await
-                .map_err(EvmActorError::from),
+                .map_err(Error::from),
             SpecificGrant::TokenTransfer(settings) => self
                 .engine
                 .create_grant::<TokenTransfer>(CombinedSettings {
@@ -155,46 +155,36 @@ impl EvmActor {
                     specific: settings,
                 })
                 .await
-                .map_err(EvmActorError::from),
+                .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<(), EvmActorError> {
-        // let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
-        // let keyholder = self.keyholder.clone();
+    pub async fn operator_delete_grant(&mut self, grant_id: i32) -> Result<(), Error> {
+        let mut conn = self.db.get().await.map_err(DatabaseError::from)?;
 
-        // diesel_async::AsyncConnection::transaction(&mut conn, |conn| {
-        //     Box::pin(async move {
-        //         diesel::update(schema::evm_basic_grant::table)
-        //             .filter(schema::evm_basic_grant::id.eq(grant_id))
-        //             .set(schema::evm_basic_grant::revoked_at.eq(SqliteTimestamp::now()))
-        //             .execute(conn)
-        //             .await?;
+        let affected = diesel::update(schema::evm_basic_grant::table)
+            .filter(schema::evm_basic_grant::id.eq(grant_id))
+            .set(schema::evm_basic_grant::revoked_at.eq(models::SqliteTimestamp::now()))
+            .execute(&mut conn)
+            .await
+            .map_err(DatabaseError::from)?;
 
-        //         let signed = integrity::evm::load_signed_grant_by_basic_id(conn, grant_id).await?;
+        if affected == 0 {
+            return Err(Error::Database(DatabaseError::from(
+                diesel::result::Error::NotFound,
+            )));
+        }
 
-        //         diesel::result::QueryResult::Ok(())
-        //     })
-        // })
-        // .await
-        // .map_err(DatabaseError::from)?;
-
-        // Ok(())
-        todo!()
+        Ok(())
     }
 
     #[message]
-    pub async fn useragent_list_grants(
-        &mut self,
-    ) -> Result<Vec<Grant<SpecificGrant>>, EvmActorError> {
+    pub async fn operator_list_grants(&mut self) -> Result<Vec<Grant<SpecificGrant>>, Error> {
         match self.engine.list_all_grants().await {
             Ok(grants) => Ok(grants),
-            Err(ListError::Database(db_err)) => Err(EvmActorError::Database(db_err)),
-            Err(ListError::Integrity(integrity_err)) => {
-                Err(EvmActorError::Integrity(integrity_err))
-            }
+            Err(ListError::Database(db_err)) => Err(Error::Database(db_err)),
+            Err(ListError::Integrity(integrity_err)) => Err(Error::Integrity(integrity_err)),
         }
     }
 
@@ -261,12 +251,12 @@ impl EvmActor {
         drop(conn);
 
         let raw_key: SafeCell<Vec<u8>> = self
-            .keyholder
+            .vault
             .ask(Decrypt {
                 aead_id: wallet.aead_encrypted_id,
             })
             .await
-            .map_err(|_| SignTransactionError::KeyholderSend)?;
+            .map_err(|_| SignTransactionError::VaultSend)?;
 
         let signer = safe_signer::SafeSigner::from_cell(raw_key)?;
 

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

@@ -1,25 +1,26 @@
-use std::ops::ControlFlow;
+use crate::{
+    actors::flow_coordinator::ApprovalError,
+    peers::{
+        client::ClientProfile,
+        operator::{OperatorSession, session::BeginNewClientApproval},
+    },
+};
 
 use kameo::{
     Actor, messages,
     prelude::{ActorId, ActorRef, ActorStopReason, Context, WeakActorRef},
     reply::ReplySender,
 };
-
-use crate::actors::{
-    client::ClientProfile,
-    flow_coordinator::ApprovalError,
-    user_agent::{UserAgentSession, session::BeginNewClientApproval},
-};
+use std::ops::ControlFlow;
 
 pub struct Args {
     pub client: ClientProfile,
-    pub user_agents: Vec<ActorRef<UserAgentSession>>,
+    pub operators: Vec<ActorRef<OperatorSession>>,
     pub reply: ReplySender<Result<bool, ApprovalError>>,
 }
 
 pub struct ClientApprovalController {
-    /// Number of UAs that have not yet responded (approval or denial) or died.
+    /// Number of operators that have not yet responded (approval or denial) or died.
     pending: usize,
     /// Number of approvals received so far.
     approved: usize,
@@ -41,21 +42,21 @@ impl Actor for ClientApprovalController {
     async fn on_start(
         Args {
             client,
-            user_agents,
+            operators,
             reply,
         }: Self::Args,
         actor_ref: ActorRef<Self>,
     ) -> Result<Self, Self::Error> {
         let this = Self {
-            pending: user_agents.len(),
+            pending: operators.len(),
             approved: 0,
             reply: Some(reply),
         };
 
-        for user_agent in user_agents {
-            actor_ref.link(&user_agent).await;
+        for operator in operators {
+            actor_ref.link(&operator).await;
 
-            let _ = user_agent
+            let _ = operator
                 .tell(BeginNewClientApproval {
                     client: client.clone(),
                     controller: actor_ref.clone(),
@@ -72,10 +73,10 @@ impl Actor for ClientApprovalController {
         _: ActorId,
         _: ActorStopReason,
     ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        // A linked UA died before responding — counts as a non-approval.
+        // A linked operator died before responding — counts as a non-approval.
         self.pending = self.pending.saturating_sub(1);
         if self.pending == 0 {
-            // At least one UA didn't approve: deny.
+            // At least one operator didn't approve: deny.
             self.send_reply(Ok(false));
             return Ok(ControlFlow::Break(ActorStopReason::Normal));
         }
@@ -98,7 +99,7 @@ impl ClientApprovalController {
         self.pending = self.pending.saturating_sub(1);
 
         if self.pending == 0 {
-            // Every connected UA approved.
+            // Every connected operator approved.
             self.send_reply(Ok(true));
             ctx.stop();
         }

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

@@ -1,4 +1,10 @@
-use std::{collections::HashMap, ops::ControlFlow};
+use crate::{
+    actors::{
+        flow_coordinator::client_connect_approval::ClientApprovalController,
+        operator_registry::{GetConnected, OperatorRegistry},
+    },
+    peers::client::{ClientProfile, session::ClientSession},
+};
 
 use kameo::{
     Actor,
@@ -7,20 +13,23 @@ 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 {
@@ -38,13 +47,7 @@ impl Actor for FlowCoordinator {
         id: ActorId,
         _: ActorStopReason,
     ) -> Result<ControlFlow<ActorStopReason>, Self::Error> {
-        if self.user_agents.remove(&id).is_some() {
-            info!(
-                ?id,
-                actor = "FlowCoordinator",
-                event = "useragent.disconnected"
-            );
-        } else if self.clients.remove(&id).is_some() {
+        if self.clients.remove(&id).is_some() {
             info!(
                 ?id,
                 actor = "FlowCoordinator",
@@ -63,23 +66,12 @@ impl Actor for FlowCoordinator {
 
 #[derive(Debug, thiserror::Error, Clone, PartialEq, Eq, Hash)]
 pub enum ApprovalError {
-    #[error("No user agents connected")]
-    NoUserAgentsConnected,
+    #[error("No operators connected")]
+    NoOperatorsConnected,
 }
 
 #[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,
@@ -92,7 +84,7 @@ impl FlowCoordinator {
     }
 
     #[message(ctx)]
-    pub fn request_client_approval(
+    pub async fn request_client_approval(
         &mut self,
         client: ClientProfile,
         ctx: &mut Context<Self, DelegatedReply<Result<bool, ApprovalError>>>,
@@ -101,15 +93,19 @@ impl FlowCoordinator {
             unreachable!("Expected `request_client_approval` to have callback channel");
         };
 
-        let refs: Vec<_> = self.user_agents.values().cloned().collect();
+        let Ok(refs) = self.operator_registry.ask(GetConnected).await else {
+            reply_sender.send(Err(ApprovalError::NoOperatorsConnected));
+            return reply;
+        };
+
         if refs.is_empty() {
-            reply_sender.send(Err(ApprovalError::NoUserAgentsConnected));
+            reply_sender.send(Err(ApprovalError::NoOperatorsConnected));
             return reply;
         }
 
         ClientApprovalController::spawn(client_connect_approval::Args {
             client,
-            user_agents: refs,
+            operators: refs,
             reply: reply_sender,
         });
 

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

@@ -1,460 +0,0 @@
-use chrono::Utc;
-use diesel::{
-    ExpressionMethods as _, OptionalExtension, QueryDsl, SelectableHelper,
-    dsl::{insert_into, update},
-};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use hmac::Mac as _;
-use kameo::{Actor, Reply, messages};
-use strum::{EnumDiscriminants, IntoDiscriminant};
-use tracing::{error, info};
-
-use crate::crypto::{
-    KeyCell, derive_key,
-    encryption::v1::{self, Nonce},
-    integrity::v1::HmacSha256,
-};
-use crate::db::{
-    self,
-    models::{self, RootKeyHistory},
-    schema::{self},
-};
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-#[derive(Default, EnumDiscriminants)]
-#[strum_discriminants(derive(Reply), vis(pub), name(KeyHolderState))]
-enum State {
-    #[default]
-    Unbootstrapped,
-    Sealed {
-        root_key_history_id: i32,
-    },
-    Unsealed {
-        root_key_history_id: i32,
-        root_key: KeyCell,
-    },
-}
-
-#[derive(Debug, thiserror::Error)]
-pub enum KeyHolderError {
-    #[error("Keyholder is already bootstrapped")]
-    AlreadyBootstrapped,
-
-    #[error("Broken database")]
-    BrokenDatabase,
-
-    #[error("Database error: {0}")]
-    DatabaseConnection(#[from] db::PoolError),
-
-    #[error("Database transaction error: {0}")]
-    DatabaseTransaction(#[from] diesel::result::Error),
-
-    #[error("Encryption error: {0}")]
-    Encryption(#[from] chacha20poly1305::aead::Error),
-
-    #[error("Invalid key provided")]
-    InvalidKey,
-
-    #[error("Keyholder is not bootstrapped")]
-    NotBootstrapped,
-
-    #[error("Requested aead entry not found")]
-    NotFound,
-}
-
-/// 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 KeyHolder {
-    db: db::DatabasePool,
-    state: State,
-}
-
-#[messages]
-impl KeyHolder {
-    pub async fn new(db: db::DatabasePool) -> Result<Self, KeyHolderError> {
-        let state = {
-            let mut conn = db.get().await?;
-
-            let (root_key_history,) = schema::arbiter_settings::table
-                .left_join(schema::root_key_history::table)
-                .select((Option::<RootKeyHistory>::as_select(),))
-                .get_result::<(Option<RootKeyHistory>,)>(&mut conn)
-                .await?;
-
-            match root_key_history {
-                Some(root_key_history) => State::Sealed {
-                    root_key_history_id: root_key_history.id,
-                },
-                None => State::Unbootstrapped,
-            }
-        };
-
-        Ok(Self { db, state })
-    }
-
-    // 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, KeyHolderError> {
-        let mut conn = pool.get().await?;
-
-        let nonce = conn
-            .exclusive_transaction(|conn| {
-                Box::pin(async move {
-                    let current_nonce: Vec<u8> = schema::root_key_history::table
-                        .filter(schema::root_key_history::id.eq(root_key_id))
-                        .select(schema::root_key_history::data_encryption_nonce)
-                        .first(conn)
-                        .await?;
-
-                    let mut nonce = Nonce::try_from(current_nonce.as_slice()).map_err(|()| {
-                        error!(
-                            "Broken database: invalid nonce for root key history id={}",
-                            root_key_id
-                        );
-                        KeyHolderError::BrokenDatabase
-                    })?;
-                    nonce.increment();
-
-                    update(schema::root_key_history::table)
-                        .filter(schema::root_key_history::id.eq(root_key_id))
-                        .set(schema::root_key_history::data_encryption_nonce.eq(nonce.to_vec()))
-                        .execute(conn)
-                        .await?;
-
-                    Result::<_, KeyHolderError>::Ok(nonce)
-                })
-            })
-            .await?;
-
-        Ok(nonce)
-    }
-
-    #[message]
-    pub async fn bootstrap(
-        &mut self,
-        seal_key_raw: SafeCell<Vec<u8>>,
-    ) -> Result<(), KeyHolderError> {
-        if !matches!(self.state, State::Unbootstrapped) {
-            return Err(KeyHolderError::AlreadyBootstrapped);
-        }
-        let salt = v1::generate_salt();
-        let mut seal_key = derive_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 data_encryption_nonce = Nonce::default();
-
-        let root_key_ciphertext: Vec<u8> = root_key.0.read_inline(|reader| {
-            let root_key_reader = reader.as_slice();
-            seal_key
-                .encrypt(&root_key_nonce, v1::ROOT_KEY_TAG, root_key_reader)
-                .map_err(|err| {
-                    error!(?err, "Fatal bootstrap error");
-                    KeyHolderError::Encryption(err)
-                })
-        })?;
-
-        let mut conn = self.db.get().await?;
-
-        let data_encryption_nonce_bytes = data_encryption_nonce.to_vec();
-        let root_key_history_id = conn
-            .transaction(|conn| {
-                Box::pin(async move {
-                    let root_key_history_id: i32 = insert_into(schema::root_key_history::table)
-                        .values(&models::NewRootKeyHistory {
-                            ciphertext: root_key_ciphertext,
-                            tag: v1::ROOT_KEY_TAG.to_vec(),
-                            root_key_encryption_nonce: root_key_nonce.to_vec(),
-                            data_encryption_nonce: data_encryption_nonce_bytes,
-                            schema_version: 1,
-                            salt: salt.to_vec(),
-                        })
-                        .returning(schema::root_key_history::id)
-                        .get_result(conn)
-                        .await?;
-
-                    update(schema::arbiter_settings::table)
-                        .set(schema::arbiter_settings::root_key_id.eq(root_key_history_id))
-                        .execute(conn)
-                        .await?;
-
-                    Result::<_, diesel::result::Error>::Ok(root_key_history_id)
-                })
-            })
-            .await?;
-
-        self.state = State::Unsealed {
-            root_key,
-            root_key_history_id,
-        };
-
-        info!("Keyholder bootstrapped successfully");
-
-        Ok(())
-    }
-
-    #[message]
-    pub async fn try_unseal(
-        &mut self,
-        seal_key_raw: SafeCell<Vec<u8>>,
-    ) -> Result<(), KeyHolderError> {
-        let State::Sealed {
-            root_key_history_id,
-        } = &self.state
-        else {
-            return Err(KeyHolderError::NotBootstrapped);
-        };
-
-        // We don't want to hold connection while doing expensive KDF work
-        let current_key = {
-            let mut conn = self.db.get().await?;
-            schema::root_key_history::table
-                .filter(schema::root_key_history::id.eq(*root_key_history_id))
-                .select(RootKeyHistory::as_select())
-                .first(&mut conn)
-                .await?
-        };
-
-        let salt = &current_key.salt;
-        let salt = v1::Salt::try_from(salt.as_slice()).map_err(|_| {
-            error!("Broken database: invalid salt for root key");
-            KeyHolderError::BrokenDatabase
-        })?;
-        let mut seal_key = derive_key(seal_key_raw, &salt);
-
-        let mut root_key = SafeCell::new(current_key.ciphertext.clone());
-
-        let nonce = Nonce::try_from(current_key.root_key_encryption_nonce.as_slice()).map_err(
-            |()| {
-                error!("Broken database: invalid nonce for root key");
-                KeyHolderError::BrokenDatabase
-            },
-        )?;
-
-        seal_key
-            .decrypt_in_place(&nonce, v1::ROOT_KEY_TAG, &mut root_key)
-            .map_err(|err| {
-                error!(?err, "Failed to unseal root key: invalid seal key");
-                KeyHolderError::InvalidKey
-            })?;
-
-        self.state = State::Unsealed {
-            root_key_history_id: current_key.id,
-            root_key: KeyCell::try_from(root_key).map_err(|err| {
-                error!(?err, "Broken database: invalid encryption key size");
-                KeyHolderError::BrokenDatabase
-            })?,
-        };
-
-        info!("Keyholder unsealed successfully");
-
-        Ok(())
-    }
-
-    #[message]
-    pub async fn decrypt(&mut self, aead_id: i32) -> Result<SafeCell<Vec<u8>>, KeyHolderError> {
-        let State::Unsealed { root_key, .. } = &mut self.state else {
-            return Err(KeyHolderError::NotBootstrapped);
-        };
-
-        let row: models::AeadEncrypted = {
-            let mut conn = self.db.get().await?;
-            schema::aead_encrypted::table
-                .select(models::AeadEncrypted::as_select())
-                .filter(schema::aead_encrypted::id.eq(aead_id))
-                .first(&mut conn)
-                .await
-                .optional()?
-                .ok_or(KeyHolderError::NotFound)?
-        };
-
-        let nonce = Nonce::try_from(row.current_nonce.as_slice()).map_err(|()| {
-            error!(
-                "Broken database: invalid nonce for aead_encrypted id={}",
-                aead_id
-            );
-            KeyHolderError::BrokenDatabase
-        })?;
-        let mut output = SafeCell::new(row.ciphertext);
-        root_key.decrypt_in_place(&nonce, v1::TAG, &mut output)?;
-        Ok(output)
-    }
-
-    // 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, KeyHolderError> {
-        let State::Unsealed {
-            root_key,
-            root_key_history_id,
-            ..
-        } = &mut self.state
-        else {
-            return Err(KeyHolderError::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
-        let nonce = Self::get_new_nonce(&self.db, *root_key_history_id).await?;
-
-        let mut ciphertext_buffer = plaintext.write();
-        let ciphertext_buffer: &mut Vec<u8> = ciphertext_buffer.as_mut();
-        root_key.encrypt_in_place(&nonce, v1::TAG, &mut *ciphertext_buffer)?;
-
-        let ciphertext = std::mem::take(ciphertext_buffer);
-
-        let mut conn = self.db.get().await?;
-        let aead_id: i32 = insert_into(schema::aead_encrypted::table)
-            .values(&models::NewAeadEncrypted {
-                ciphertext,
-                tag: v1::TAG.to_vec(),
-                current_nonce: nonce.to_vec(),
-                schema_version: 1,
-                associated_root_key_id: *root_key_history_id,
-                created_at: Utc::now().into(),
-            })
-            .returning(schema::aead_encrypted::id)
-            .get_result(&mut conn)
-            .await?;
-
-        Ok(aead_id)
-    }
-
-    #[message]
-    pub fn get_state(&self) -> KeyHolderState {
-        self.state.discriminant()
-    }
-
-    #[message]
-    pub fn sign_integrity(&mut self, mac_input: Vec<u8>) -> Result<(i32, Vec<u8>), KeyHolderError> {
-        let State::Unsealed {
-            root_key,
-            root_key_history_id,
-        } = &mut self.state
-        else {
-            return Err(KeyHolderError::NotBootstrapped);
-        };
-
-        let mut hmac = root_key.0.read_inline(|k| {
-            HmacSha256::new_from_slice(k)
-                .unwrap_or_else(|_| 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, KeyHolderError> {
-        let State::Unsealed {
-            root_key,
-            root_key_history_id,
-        } = &mut self.state
-        else {
-            return Err(KeyHolderError::NotBootstrapped);
-        };
-
-        if *root_key_history_id != key_version {
-            return Ok(false);
-        }
-
-        let mut hmac = root_key.0.read_inline(|k| {
-            HmacSha256::new_from_slice(k)
-                .unwrap_or_else(|_| 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 fn seal(&mut self) -> Result<(), KeyHolderError> {
-        let State::Unsealed {
-            root_key_history_id,
-            ..
-        } = &self.state
-        else {
-            return Err(KeyHolderError::NotBootstrapped);
-        };
-        self.state = State::Sealed {
-            root_key_history_id: *root_key_history_id,
-        };
-        Ok(())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use arbiter_crypto::safecell::SafeCellHandle as _;
-
-    use super::*;
-
-    async fn bootstrapped_actor(db: &db::DatabasePool) -> KeyHolder {
-        let mut actor = KeyHolder::new(db.clone()).await.unwrap();
-        let seal_key = SafeCell::new(b"test-seal-key".to_vec());
-        actor.bootstrap(seal_key).await.unwrap();
-        actor
-    }
-
-    #[tokio::test]
-    #[test_log::test]
-    async fn nonce_monotonic_even_when_nonce_allocation_interleaves() {
-        let db = db::create_test_pool().await;
-        let mut actor = bootstrapped_actor(&db).await;
-        let State::Unsealed {
-            root_key_history_id,
-            ..
-        } = actor.state
-        else {
-            panic!("expected unsealed state");
-        };
-
-        let n1 = KeyHolder::get_new_nonce(&db, root_key_history_id)
-            .await
-            .unwrap();
-        let n2 = KeyHolder::get_new_nonce(&db, root_key_history_id)
-            .await
-            .unwrap();
-        assert!(n2.to_vec() > n1.to_vec(), "nonce must increase");
-
-        let mut conn = db.get().await.unwrap();
-        let root_row = schema::root_key_history::table
-            .select(RootKeyHistory::as_select())
-            .first(&mut conn)
-            .await
-            .unwrap();
-        assert_eq!(root_row.data_encryption_nonce, n2.to_vec());
-
-        let id = actor
-            .create_new(SafeCell::new(b"post-interleave".to_vec()))
-            .await
-            .unwrap();
-        let row: models::AeadEncrypted = schema::aead_encrypted::table
-            .filter(schema::aead_encrypted::id.eq(id))
-            .select(models::AeadEncrypted::as_select())
-            .first(&mut conn)
-            .await
-            .unwrap();
-        assert!(
-            row.current_nonce > n2.to_vec(),
-            "next write must advance nonce"
-        );
-    }
-}

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

@@ -1,47 +1,76 @@
-use kameo::actor::{ActorRef, Spawn};
-use thiserror::Error;
-
 use crate::{
     actors::{
         bootstrap::Bootstrapper, evm::EvmActor, flow_coordinator::FlowCoordinator,
-        keyholder::KeyHolder,
+        operator_registry::OperatorRegistry, proposal_manager::ProposalManager, vault::Vault,
+        vault_coordinator::VaultCoordinator,
     },
     db,
 };
 
+use kameo::actor::{ActorRef, Spawn};
+use kameo_actors::{DeliveryStrategy, message_bus::MessageBus};
+use thiserror::Error;
+
 pub mod bootstrap;
-pub mod client;
 pub mod evm;
 pub mod flow_coordinator;
-pub mod keyholder;
-pub mod user_agent;
+pub mod operator_registry;
+pub mod proposal_manager;
+pub mod vault;
+pub mod vault_coordinator;
 
 #[derive(Error, Debug)]
-pub enum GlobalActorsSpawnError {
+pub enum SpawnError {
     #[error("Failed to spawn Bootstrapper actor")]
-    Bootstrapper(#[from] bootstrap::BootstrappError),
+    Bootstrapper(#[from] bootstrap::Error),
 
-    #[error("Failed to spawn KeyHolder actor")]
-    KeyHolder(#[from] keyholder::KeyHolderError),
+    #[error("Failed to spawn Vault actor")]
+    Vault(#[from] vault::Error),
 }
 
 /// Long-lived actors that are shared across all connections and handle global state and operations
 #[derive(Clone)]
 pub struct GlobalActors {
-    pub key_holder: ActorRef<KeyHolder>,
+    pub vault: ActorRef<Vault>,
     pub bootstrapper: ActorRef<Bootstrapper>,
+    pub vault_coordinator: ActorRef<VaultCoordinator>,
     pub flow_coordinator: ActorRef<FlowCoordinator>,
+    pub operator_registry: ActorRef<OperatorRegistry>,
     pub evm: ActorRef<EvmActor>,
+    pub proposal_manager: ActorRef<ProposalManager>,
+    pub events: ActorRef<MessageBus>,
 }
 
 impl GlobalActors {
-    pub async fn spawn(db: db::DatabasePool) -> Result<Self, GlobalActorsSpawnError> {
-        let key_holder = KeyHolder::spawn(KeyHolder::new(db.clone()).await?);
+    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 = Vault::spawn(Vault::new(db.clone(), message_bus.clone()).await?);
+        let operator_registry = OperatorRegistry::spawn(OperatorRegistry::default());
+        let evm = EvmActor::spawn(EvmActor::new(key_holder.clone(), db.clone()));
+        let vault_coordinator = VaultCoordinator::spawn(VaultCoordinator::new(
+            db.clone(),
+            key_holder.clone(),
+        ));
         Ok(Self {
             bootstrapper: Bootstrapper::spawn(Bootstrapper::new(&db).await?),
-            evm: EvmActor::spawn(EvmActor::new(key_holder.clone(), db)),
-            key_holder,
-            flow_coordinator: FlowCoordinator::spawn(FlowCoordinator::default()),
+            proposal_manager: ProposalManager::spawn(ProposalManager::new(
+                db,
+                key_holder.clone(),
+                evm.clone(),
+                vault_coordinator.clone(),
+            )),
+            vault: key_holder,
+            vault_coordinator,
+            flow_coordinator: FlowCoordinator::spawn(FlowCoordinator::new(
+                operator_registry.clone(),
+            )),
+            operator_registry,
+            events: message_bus,
+            evm,
         })
     }
 }

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

@@ -0,0 +1,61 @@
+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/state.rs

@@ -1,308 +0,0 @@
-use arbiter_crypto::authn::{self, USERAGENT_CONTEXT};
-use arbiter_proto::transport::Bi;
-use diesel::{ExpressionMethods as _, OptionalExtension as _, QueryDsl, update};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use kameo::actor::ActorRef;
-use tracing::error;
-
-use super::Error;
-use crate::{
-    actors::{
-        bootstrap::ConsumeToken,
-        keyholder::KeyHolder,
-        user_agent::{UserAgentConnection, UserAgentCredentials, auth::Outbound},
-    },
-    crypto::integrity,
-    db::{DatabasePool, schema::useragent_client},
-};
-
-pub struct ChallengeRequest {
-    pub pubkey: authn::PublicKey,
-}
-
-pub struct BootstrapAuthRequest {
-    pub pubkey: authn::PublicKey,
-    pub token: String,
-}
-
-pub struct ChallengeContext {
-    pub challenge_nonce: i32,
-    pub key: authn::PublicKey,
-}
-
-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(authn::PublicKey),
-        SentChallenge(ChallengeContext) + ReceivedSolution(ChallengeSolution) / async verify_solution = AuthOk(authn::PublicKey),
-    }
-);
-
-/// Returns the current nonce, ready to use for the challenge nonce.
-async fn get_current_nonce_and_id(
-    db: &DatabasePool,
-    key: &authn::PublicKey,
-) -> Result<(i32, 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 {
-                useragent_client::table
-                    .filter(useragent_client::public_key.eq(key.to_bytes()))
-                    .select((useragent_client::id, useragent_client::nonce))
-                    .first::<(i32, i32)>(conn)
-                    .await
-            })
-        })
-        .await
-        .optional()
-        .map_err(|e| {
-            error!(error = ?e, "Database error");
-            Error::internal("Database operation failed")
-        })?
-        .ok_or_else(|| {
-            error!(?key, "Public key not found in database");
-            Error::UnregisteredPublicKey
-        })
-}
-
-async fn verify_integrity(
-    db: &DatabasePool,
-    keyholder: &ActorRef<KeyHolder>,
-    pubkey: &authn::PublicKey,
-) -> Result<(), Error> {
-    let mut db_conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        Error::internal("Database unavailable")
-    })?;
-
-    let (id, nonce) = get_current_nonce_and_id(db, pubkey).await?;
-
-    let _result = integrity::verify_entity(
-        &mut db_conn,
-        keyholder,
-        &UserAgentCredentials {
-            pubkey: pubkey.clone(),
-            nonce,
-        },
-        id,
-    )
-    .await
-    .map_err(|e| {
-        error!(?e, "Integrity verification failed");
-        Error::internal("Integrity verification failed")
-    })?;
-
-    Ok(())
-}
-
-async fn create_nonce(
-    db: &DatabasePool,
-    keyholder: &ActorRef<KeyHolder>,
-    pubkey: &authn::PublicKey,
-) -> Result<i32, Error> {
-    let mut db_conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        Error::internal("Database unavailable")
-    })?;
-    let new_nonce = db_conn
-        .exclusive_transaction(|conn| {
-            Box::pin(async move {
-                let (id, new_nonce): (i32, i32) = update(useragent_client::table)
-                    .filter(useragent_client::public_key.eq(pubkey.to_bytes()))
-                    .set(useragent_client::nonce.eq(useragent_client::nonce + 1))
-                    .returning((useragent_client::id, useragent_client::nonce))
-                    .get_result(conn)
-                    .await
-                    .map_err(|e| {
-                        error!(error = ?e, "Database error");
-                        Error::internal("Database operation failed")
-                    })?;
-
-                integrity::sign_entity(
-                    conn,
-                    keyholder,
-                    &UserAgentCredentials {
-                        pubkey: pubkey.clone(),
-                        nonce: new_nonce,
-                    },
-                    id,
-                )
-                .await
-                .map_err(|e| {
-                    error!(?e, "Integrity signature update failed");
-                    Error::internal("Database error")
-                })?;
-
-                Result::<_, Error>::Ok(new_nonce)
-            })
-        })
-        .await?;
-    Ok(new_nonce)
-}
-
-async fn register_key(
-    db: &DatabasePool,
-    keyholder: &ActorRef<KeyHolder>,
-    pubkey: &authn::PublicKey,
-) -> Result<(), Error> {
-    let pubkey_bytes = pubkey.to_bytes();
-    let mut conn = db.get().await.map_err(|e| {
-        error!(error = ?e, "Database pool error");
-        Error::internal("Database unavailable")
-    })?;
-
-    conn.transaction(|conn| {
-        Box::pin(async move {
-            const NONCE_START: i32 = 1;
-
-            let id: i32 = diesel::insert_into(useragent_client::table)
-                .values((
-                    useragent_client::public_key.eq(pubkey_bytes),
-                    useragent_client::nonce.eq(NONCE_START),
-                ))
-                .returning(useragent_client::id)
-                .get_result(conn)
-                .await
-                .map_err(|e| {
-                    error!(error = ?e, "Database error");
-                    Error::internal("Database operation failed")
-                })?;
-
-            let entity = UserAgentCredentials {
-                pubkey: pubkey.clone(),
-                nonce: NONCE_START,
-            };
-
-            integrity::sign_entity(conn, keyholder, &entity, id)
-                .await
-                .map_err(|e| {
-                    error!(error = ?e, "Failed to sign integrity tag for new user-agent key");
-                    Error::internal("Failed to register public key")
-                })?;
-
-            Result::<_, Error>::Ok(())
-        })
-    })
-    .await?;
-
-    Ok(())
-}
-
-pub struct AuthContext<'a, T> {
-    pub(super) conn: &'a mut UserAgentConnection,
-    pub(super) transport: T,
-}
-
-impl<'a, T> AuthContext<'a, T> {
-    pub const fn new(conn: &'a mut UserAgentConnection, transport: T) -> Self {
-        Self { conn, transport }
-    }
-}
-
-impl<T> AuthStateMachineContext for AuthContext<'_, T>
-where
-    T: Bi<super::Inbound, Result<Outbound, Error>> + Send,
-{
-    type Error = Error;
-
-    async fn prepare_challenge(
-        &mut self,
-        ChallengeRequest { pubkey }: ChallengeRequest,
-    ) -> Result<ChallengeContext, Self::Error> {
-        verify_integrity(&self.conn.db, &self.conn.actors.key_holder, &pubkey).await?;
-
-        let nonce = create_nonce(&self.conn.db, &self.conn.actors.key_holder, &pubkey).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,
-        })
-    }
-
-    async fn verify_bootstrap_token(
-        &mut self,
-        BootstrapAuthRequest { pubkey, token }: BootstrapAuthRequest,
-    ) -> Result<authn::PublicKey, 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);
-        }
-
-        if token_ok {
-            register_key(&self.conn.db, &self.conn.actors.key_holder, &pubkey).await?;
-            self.transport
-                .send(Ok(Outbound::AuthSuccess))
-                .await
-                .map_err(|_| Error::Transport)?;
-            Ok(pubkey)
-        } else {
-            error!("Invalid bootstrap token provided");
-            self.transport
-                .send(Err(Error::InvalidBootstrapToken))
-                .await
-                .map_err(|_| Error::Transport)?;
-            Err(Error::InvalidBootstrapToken)
-        }
-    }
-
-    async fn verify_solution(
-        &mut self,
-        ChallengeContext {
-            challenge_nonce,
-            key,
-        }: &ChallengeContext,
-        ChallengeSolution { solution }: ChallengeSolution,
-    ) -> Result<authn::PublicKey, Self::Error> {
-        let signature = authn::Signature::try_from(solution.as_slice()).map_err(|()| {
-            error!("Failed to decode signature in challenge solution");
-            Error::InvalidChallengeSolution
-        })?;
-
-        let valid = key.verify(*challenge_nonce, USERAGENT_CONTEXT, &signature);
-
-        if valid {
-            self.transport
-                .send(Ok(Outbound::AuthSuccess))
-                .await
-                .map_err(|_| Error::Transport)?;
-            Ok(key.clone())
-        } else {
-            self.transport
-                .send(Err(Error::InvalidChallengeSolution))
-                .await
-                .map_err(|_| Error::Transport)?;
-            Err(Error::InvalidChallengeSolution)
-        }
-    }
-}

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

@@ -1,40 +0,0 @@
-use crate::{
-    actors::{GlobalActors, client::ClientProfile},
-    crypto::integrity::Integrable,
-    db,
-};
-use arbiter_crypto::authn;
-
-#[derive(Debug, arbiter_macros::Hashable)]
-pub struct UserAgentCredentials {
-    pub pubkey: authn::PublicKey,
-    pub nonce: i32,
-}
-
-impl Integrable for UserAgentCredentials {
-    const KIND: &'static str = "useragent_credentials";
-}
-
-// Messages, sent by user agent to connection client without having a request
-#[derive(Debug)]
-pub enum OutOfBand {
-    ClientConnectionRequest { profile: ClientProfile },
-    ClientConnectionCancel { pubkey: authn::PublicKey },
-}
-
-pub struct UserAgentConnection {
-    pub(crate) db: db::DatabasePool,
-    pub(crate) actors: GlobalActors,
-}
-
-impl UserAgentConnection {
-    pub const 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/connection.rs

@@ -1,534 +0,0 @@
-use std::sync::Mutex;
-
-use alloy::{consensus::TxEip1559, primitives::Address, signers::Signature};
-use arbiter_crypto::{
-    authn,
-    safecell::{SafeCell, SafeCellHandle as _},
-};
-use chacha20poly1305::{AeadInPlace, XChaCha20Poly1305, XNonce, aead::KeyInit};
-use diesel::{ExpressionMethods as _, QueryDsl as _, SelectableHelper};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use kameo::error::SendError;
-use kameo::messages;
-use kameo::prelude::Context;
-use thiserror::Error;
-use tracing::{error, info};
-use x25519_dalek::{EphemeralSecret, PublicKey};
-
-use crate::{actors::flow_coordinator::client_connect_approval::ClientApprovalAnswer, evm::policies::SharedGrantSettings};
-use crate::actors::keyholder::KeyHolderState;
-use crate::actors::user_agent::session::UserAgentSessionError;
-use crate::actors::{
-    evm::{
-        ClientSignTransaction, Generate, ListWallets, SignTransactionError as EvmSignError,
-        UseragentCreateGrant, UseragentListGrants,
-    },
-    keyholder::{self, Bootstrap, TryUnseal},
-    user_agent::session::{
-        UserAgentSession,
-        state::{UnsealContext, UserAgentEvents, UserAgentStates},
-    },
-};
-use crate::db::models::{
-    EvmWalletAccess, NewEvmWalletAccess, ProgramClient, ProgramClientMetadata,
-};
-use crate::evm::policies::{Grant, SpecificGrant};
-
-impl UserAgentSession {
-    fn take_unseal_secret(&self) -> Result<(EphemeralSecret, PublicKey), UserAgentSessionError> {
-        let UserAgentStates::WaitingForUnsealKey(unseal_context) = self.state.state() else {
-            error!("Received encrypted key in invalid state");
-            return Err(UserAgentSessionError::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();
-            if let Some(secret) = secret {
-                secret
-            } else {
-                drop(secret_lock);
-                error!("Ephemeral secret already taken");
-                return Err(UserAgentSessionError::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] UserAgentSessionError),
-}
-
-#[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] UserAgentSessionError),
-}
-
-#[derive(Debug, Error)]
-pub enum SignTransactionError {
-    #[error("Policy evaluation failed")]
-    Vet(#[from] crate::evm::VetError),
-
-    #[error("Internal signing error")]
-    Internal,
-}
-
-#[derive(Debug, Error)]
-pub enum GrantMutationError {
-    #[error("Vault is sealed")]
-    VaultSealed,
-
-    #[error("Internal grant mutation error")]
-    Internal,
-}
-
-#[messages]
-impl UserAgentSession {
-    #[message]
-    pub fn handle_unseal_request(
-        &mut self,
-        client_pubkey: PublicKey,
-    ) -> Result<UnsealStartResponse, UserAgentSessionError> {
-        let secret = EphemeralSecret::random();
-        let public_key = PublicKey::from(&secret);
-
-        self.transition(UserAgentEvents::UnsealRequest(UnsealContext {
-            client_public_key: client_pubkey,
-            secret: Mutex::new(Some(secret)),
-        }))?;
-
-        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(UserAgentSessionError::State) => {
-                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
-                return Err(UnsealError::InvalidKey);
-            }
-            Err(_err) => {
-                return Err(UserAgentSessionError::internal("Failed to take unseal secret").into());
-            }
-        };
-
-        let Ok(seal_key_buffer) = Self::decrypt_client_key_material(
-            ephemeral_secret,
-            client_public_key,
-            &nonce,
-            &ciphertext,
-            &associated_data,
-        ) else {
-            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::KeyHolderError::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(UserAgentSessionError::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(UserAgentSessionError::State) => {
-                self.transition(UserAgentEvents::ReceivedInvalidKey)?;
-                return Err(BootstrapError::InvalidKey);
-            }
-            Err(err) => return Err(err.into()),
-        };
-
-        let Ok(seal_key_buffer) = Self::decrypt_client_key_material(
-            ephemeral_secret,
-            client_public_key,
-            &nonce,
-            &ciphertext,
-            &associated_data,
-        ) else {
-            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::KeyHolderError::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(UserAgentSessionError::internal(
-                    "Vault actor error",
-                )))
-            }
-        }
-    }
-}
-
-#[messages]
-impl UserAgentSession {
-    #[message]
-    pub(crate) async fn handle_query_vault_state(
-        &mut self,
-    ) -> Result<KeyHolderState, UserAgentSessionError> {
-        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(UserAgentSessionError::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), UserAgentSessionError> {
-        match self.props.actors.evm.ask(Generate {}).await {
-            Ok(address) => Ok(address),
-            Err(SendError::HandlerError(err)) => Err(UserAgentSessionError::internal(format!(
-                "EVM wallet generation failed: {err}"
-            ))),
-            Err(err) => {
-                error!(?err, "EVM actor unreachable during wallet create");
-                Err(UserAgentSessionError::internal("EVM actor unreachable"))
-            }
-        }
-    }
-
-    #[message]
-    pub(crate) async fn handle_evm_wallet_list(
-        &mut self,
-    ) -> Result<Vec<(i32, Address)>, UserAgentSessionError> {
-        match self.props.actors.evm.ask(ListWallets {}).await {
-            Ok(wallets) => Ok(wallets),
-            Err(err) => {
-                error!(?err, "EVM wallet list failed");
-                Err(UserAgentSessionError::internal(
-                    "Failed to list EVM wallets",
-                ))
-            }
-        }
-    }
-}
-
-#[messages]
-impl UserAgentSession {
-    #[message]
-    pub(crate) async fn handle_grant_list(
-        &mut self,
-    ) -> Result<Vec<Grant<SpecificGrant>>, UserAgentSessionError> {
-        match self.props.actors.evm.ask(UseragentListGrants {}).await {
-            Ok(grants) => Ok(grants),
-            Err(err) => {
-                error!(?err, "EVM grant list failed");
-                Err(UserAgentSessionError::internal("Failed to list EVM grants"))
-            }
-        }
-    }
-
-    #[message]
-    pub(crate) async fn handle_grant_create(
-        &mut self,
-        basic: SharedGrantSettings,
-        grant: SpecificGrant,
-    ) -> Result<i32, GrantMutationError> {
-        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(GrantMutationError::Internal)
-            }
-        }
-    }
-
-    #[message]
-    #[expect(clippy::unused_async, reason = "false positive")]
-    pub(crate) async fn handle_grant_delete(
-        &mut self,
-        grant_id: i32,
-    ) -> Result<(), GrantMutationError> {
-        // match self
-        //     .props
-        //     .actors
-        //     .evm
-        //     .ask(UseragentDeleteGrant { grant_id })
-        //     .await
-        // {
-        //     Ok(()) => Ok(()),
-        //     Err(err) => {
-        //         error!(?err, "EVM grant delete failed");
-        //         Err(GrantMutationError::Internal)
-        //     }
-        // }
-        let _ = grant_id;
-        todo!()
-    }
-
-    #[message]
-    pub(crate) async fn handle_sign_transaction(
-        &mut self,
-        client_id: i32,
-        wallet_address: Address,
-        transaction: TxEip1559,
-    ) -> Result<Signature, SignTransactionError> {
-        match self
-            .props
-            .actors
-            .evm
-            .ask(ClientSignTransaction {
-                client_id,
-                wallet_address,
-                transaction,
-            })
-            .await
-        {
-            Ok(signature) => Ok(signature),
-            Err(SendError::HandlerError(EvmSignError::Vet(vet_error))) => {
-                Err(SignTransactionError::Vet(vet_error))
-            }
-            Err(err) => {
-                error!(?err, "EVM sign transaction failed in user-agent session");
-                Err(SignTransactionError::Internal)
-            }
-        }
-    }
-
-    #[message]
-    pub(crate) async fn handle_grant_evm_wallet_access(
-        &mut self,
-        entries: Vec<NewEvmWalletAccess>,
-    ) -> Result<(), UserAgentSessionError> {
-        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::<_, UserAgentSessionError>::Ok(())
-            })
-        })
-        .await?;
-        Ok(())
-    }
-
-    #[message]
-    pub(crate) async fn handle_revoke_evm_wallet_access(
-        &mut self,
-        entries: Vec<i32>,
-    ) -> Result<(), UserAgentSessionError> {
-        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::<_, UserAgentSessionError>::Ok(())
-            })
-        })
-        .await?;
-        Ok(())
-    }
-
-    #[message]
-    pub(crate) async fn handle_list_wallet_access(
-        &mut self,
-    ) -> Result<Vec<EvmWalletAccess>, UserAgentSessionError> {
-        let mut conn = self.props.db.get().await?;
-        let access_entries = crate::db::schema::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: authn::PublicKey,
-        ctx: &Context<Self, Result<(), UserAgentSessionError>>,
-    ) -> Result<(), UserAgentSessionError> {
-        let Some(pending_approval) = self.pending_client_approvals.remove(&pubkey.to_bytes())
-        else {
-            error!("Received client connection response for unknown client");
-            return Err(UserAgentSessionError::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"
-                );
-                UserAgentSessionError::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)>, UserAgentSessionError> {
-        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

@@ -1,25 +0,0 @@
-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 {
-    fn generate_temp_keypair(&mut self, event_data: UnsealContext) -> Result<UnsealContext, ()> {
-        Ok(event_data)
-    }
-}

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

@@ -0,0 +1,523 @@
+use crate::{
+    crypto::{
+        KeyCell,
+        encryption::v1::{self, Nonce},
+        integrity::v1::HmacSha256,
+    },
+    db::{
+        self,
+        models::{self, RootKeyHistory, RootKeyHistoryId},
+        schema,
+    },
+};
+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, actor::ActorRef, messages};
+use kameo_actors::message_bus::{MessageBus, Publish};
+use strum::{EnumDiscriminants, IntoDiscriminant};
+use tracing::{error, info};
+
+pub mod events {
+    #[derive(Clone, Copy)]
+    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: RootKeyHistoryId,
+    root_key: KeyCell,
+}
+
+#[derive(Default, EnumDiscriminants)]
+#[strum_discriminants(derive(Reply), vis(pub), name(VaultState))]
+enum State {
+    #[default]
+    Unbootstrapped,
+
+    Sealed {
+        root_key_history_id: RootKeyHistoryId,
+    },
+    Unsealed(Unsealed),
+}
+
+/// 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 {
+    db: db::DatabasePool,
+    state: State,
+    events: ActorRef<MessageBus>,
+}
+
+impl Vault {
+    pub async fn new(db: db::DatabasePool, events: ActorRef<MessageBus>) -> Result<Self, Error> {
+        let state = {
+            let mut conn = db.get().await?;
+
+            let (root_key_history,) = schema::arbiter_settings::table
+                .left_join(schema::root_key_history::table)
+                .select((Option::<RootKeyHistory>::as_select(),))
+                .get_result::<(Option<RootKeyHistory>,)>(&mut conn)
+                .await?;
+
+            match root_key_history {
+                Some(root_key_history) => State::Sealed {
+                    root_key_history_id: root_key_history.id,
+                },
+                None => State::Unbootstrapped,
+            }
+        };
+
+        Ok(Self { db, state, events })
+    }
+
+    // Exclusive transaction to avoid race conditions if multiple vaults write
+    // additional layer of protection against nonce-reuse
+    async fn get_new_nonce(
+        pool: &db::DatabasePool,
+        root_key_id: RootKeyHistoryId,
+    ) -> Result<Nonce, Error> {
+        let mut conn = pool.get().await?;
+
+        let nonce = conn
+            .exclusive_transaction(async |conn| {
+                let current_nonce: Vec<u8> = schema::root_key_history::table
+                    .filter(schema::root_key_history::id.eq(root_key_id))
+                    .select(schema::root_key_history::data_encryption_nonce)
+                    .first(&mut *conn)
+                    .await?;
+
+                let mut nonce = Nonce::try_from(current_nonce.as_slice()).map_err(|()| {
+                    error!(
+                        "Broken database: invalid nonce for root key history id={:#?}",
+                        root_key_id
+                    );
+                    Error::BrokenDatabase
+                })?;
+                nonce.increment();
+
+                update(schema::root_key_history::table)
+                    .filter(schema::root_key_history::id.eq(root_key_id))
+                    .set(schema::root_key_history::data_encryption_nonce.eq(nonce.to_vec()))
+                    .execute(&mut *conn)
+                    .await?;
+
+                Result::<_, Error>::Ok(nonce)
+            })
+            .await?;
+
+        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),
+        }
+    }
+}
+
+#[messages]
+impl Vault {
+    #[message]
+    pub async fn bootstrap(&mut self, mut seal_key: KeyCell) -> Result<(), Error> {
+        if !matches!(&self.state, State::Unbootstrapped) {
+            return Err(Error::AlreadyBootstrapped);
+        }
+
+        let mut root_key = KeyCell::new_secure_random();
+
+        // Zero nonces are fine because they are one-time
+        let root_key_nonce = Nonce::default();
+        let data_encryption_nonce = Nonce::default();
+
+        // Generate salt (kept for schema compat)
+        let root_key_salt = v1::generate_salt();
+
+        let root_key_ciphertext: Vec<u8> = root_key.0.read_inline(|rk| {
+            seal_key
+                .encrypt(&root_key_nonce, v1::ROOT_KEY_TAG, rk.as_slice())
+                .map_err(|err| {
+                    error!(?err, "Fatal bootstrap error");
+                    Error::Encryption(err)
+                })
+        })?;
+
+        let data_encryption_nonce_bytes = data_encryption_nonce.to_vec();
+        let mut conn = self.db.get().await?;
+
+        let root_key_history_id = conn
+            .transaction(async |conn| {
+                let root_key_history_id = insert_into(schema::root_key_history::table)
+                    .values(&models::NewRootKeyHistory {
+                        ciphertext: root_key_ciphertext.clone(),
+                        tag: v1::ROOT_KEY_TAG.to_vec(),
+                        root_key_encryption_nonce: root_key_nonce.to_vec(),
+                        data_encryption_nonce: data_encryption_nonce_bytes.clone(),
+                        schema_version: 1,
+                        salt: root_key_salt.to_vec(),
+                    })
+                    .returning(schema::root_key_history::id)
+                    .get_result(&mut *conn)
+                    .await?;
+
+                update(schema::arbiter_settings::table)
+                    .set(schema::arbiter_settings::root_key_id.eq(root_key_history_id))
+                    .execute(&mut *conn)
+                    .await?;
+
+                Result::<_, diesel::result::Error>::Ok(RootKeyHistoryId::from_raw(
+                    root_key_history_id,
+                ))
+            })
+            .await?;
+
+        self.state = State::Unsealed(Unsealed {
+            root_key,
+            root_key_history_id,
+        });
+
+        info!("Vault bootstrapped successfully");
+        let _ = self.events.tell(Publish(events::Bootstrapped)).await;
+
+        Ok(())
+    }
+
+    #[message]
+    pub async fn try_unseal(&mut self, mut seal_key: KeyCell) -> Result<(), Error> {
+        let State::Sealed {
+            root_key_history_id,
+        } = &self.state
+        else {
+            return Err(Error::NotBootstrapped);
+        };
+        let root_key_history_id = *root_key_history_id;
+
+        // We don't want to hold connection while doing expensive work
+        let current_key = {
+            let mut conn = self.db.get().await?;
+            schema::root_key_history::table
+                .filter(schema::root_key_history::id.eq(root_key_history_id))
+                .select(RootKeyHistory::as_select())
+                .first(&mut conn)
+                .await?
+        };
+
+        let nonce =
+            Nonce::try_from(current_key.root_key_encryption_nonce.as_slice()).map_err(|()| {
+                error!("Broken database: invalid nonce for root key");
+                Error::BrokenDatabase
+            })?;
+
+        let mut root_key_bytes = SafeCell::new(current_key.ciphertext.clone());
+        seal_key
+            .decrypt_in_place(&nonce, v1::ROOT_KEY_TAG, &mut root_key_bytes)
+            .map_err(|err| {
+                error!(?err, "Failed to unseal root key: invalid seal key");
+                Error::InvalidKey
+            })?;
+
+        let root_key = KeyCell::try_from(root_key_bytes).map_err(|()| {
+            error!("Broken database: invalid encryption key size");
+            Error::BrokenDatabase
+        })?;
+
+        self.state = State::Unsealed(Unsealed {
+            root_key_history_id: current_key.id,
+            root_key,
+        });
+
+        info!("Vault unsealed successfully");
+        let _ = self.events.tell(Publish(events::Unsealed)).await;
+
+        Ok(())
+    }
+
+    /// Re-encrypts the root key with `new_seal_key` and records a new root_key_history row.
+    /// Called after a Shamir re-key so the old seal key is no longer sufficient to unseal.
+    #[message]
+    pub async fn rekey_root_key(&mut self, mut new_seal_key: KeyCell) -> Result<(), Error> {
+        let Unsealed {
+            root_key,
+            root_key_history_id,
+        } = Self::expect_unsealed(&mut self.state)?;
+
+        let new_nonce = Nonce::default();
+        let new_salt = v1::generate_salt();
+
+        let new_ciphertext: Vec<u8> = root_key.0.read_inline(|rk| {
+            new_seal_key
+                .encrypt(&new_nonce, v1::ROOT_KEY_TAG, rk.as_slice())
+                .map_err(|err| {
+                    error!(?err, "Fatal rekey error");
+                    Error::Encryption(err)
+                })
+        })?;
+
+        let data_encryption_nonce = Nonce::default();
+
+        let mut conn = self.db.get().await?;
+        let new_root_key_history_id: i32 = conn
+            .transaction(async |conn| {
+                let new_id = insert_into(schema::root_key_history::table)
+                    .values(&models::NewRootKeyHistory {
+                        ciphertext: new_ciphertext,
+                        tag: v1::ROOT_KEY_TAG.to_vec(),
+                        root_key_encryption_nonce: new_nonce.to_vec(),
+                        data_encryption_nonce: data_encryption_nonce.to_vec(),
+                        schema_version: 1,
+                        salt: new_salt.to_vec(),
+                    })
+                    .returning(schema::root_key_history::id)
+                    .get_result::<i32>(&mut *conn)
+                    .await?;
+
+                update(schema::arbiter_settings::table)
+                    .set(schema::arbiter_settings::root_key_id.eq(new_id))
+                    .execute(&mut *conn)
+                    .await?;
+
+                Result::<_, diesel::result::Error>::Ok(new_id)
+            })
+            .await?;
+
+        *root_key_history_id = RootKeyHistoryId::from_raw(new_root_key_history_id);
+        info!("Vault root key rekeyed successfully");
+        Ok(())
+    }
+
+    #[message]
+    pub async fn seal(&mut self) -> Result<(), Error> {
+        let Unsealed {
+            root_key_history_id,
+            ..
+        } = Self::expect_unsealed(&mut self.state)?;
+
+        self.state = State::Sealed {
+            root_key_history_id: *root_key_history_id,
+        };
+        let _ = self.events.tell(Publish(events::VaultResealed)).await;
+        Ok(())
+    }
+}
+
+// Server-side cryptographic operations
+#[messages]
+impl Vault {
+    #[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 row: models::AeadEncrypted = {
+            let mut conn = self.db.get().await?;
+            schema::aead_encrypted::table
+                .select(models::AeadEncrypted::as_select())
+                .filter(schema::aead_encrypted::id.eq(aead_id))
+                .first(&mut conn)
+                .await
+                .optional()?
+                .ok_or(Error::NotFound)?
+        };
+
+        let nonce = Nonce::try_from(row.current_nonce.as_slice()).map_err(|()| {
+            error!(
+                "Broken database: invalid nonce for aead_encrypted id={}",
+                aead_id
+            );
+            Error::BrokenDatabase
+        })?;
+        let mut output = SafeCell::new(row.ciphertext);
+        root_key.decrypt_in_place(&nonce, v1::TAG, &mut output)?;
+        Ok(output)
+    }
+
+    // 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 {
+            root_key,
+            root_key_history_id,
+        } = Self::expect_unsealed(&mut self.state)?;
+
+        // 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
+        let nonce = Self::get_new_nonce(&self.db, *root_key_history_id).await?;
+
+        let mut ciphertext_buffer = plaintext.write();
+        let ciphertext_buffer: &mut Vec<u8> = ciphertext_buffer.as_mut();
+        root_key.encrypt_in_place(&nonce, v1::TAG, &mut *ciphertext_buffer)?;
+
+        let ciphertext = std::mem::take(ciphertext_buffer);
+
+        let mut conn = self.db.get().await?;
+        let aead_id: i32 = insert_into(schema::aead_encrypted::table)
+            .values(&models::NewAeadEncrypted {
+                ciphertext,
+                tag: v1::TAG.to_vec(),
+                current_nonce: nonce.to_vec(),
+                schema_version: 1,
+                associated_root_key_id: *root_key_history_id,
+                created_at: Utc::now().into(),
+            })
+            .returning(schema::aead_encrypted::id)
+            .get_result(&mut conn)
+            .await?;
+
+        Ok(aead_id)
+    }
+
+    #[message]
+    pub fn get_state(&self) -> VaultState {
+        self.state.discriminant()
+    }
+
+    #[message]
+    pub fn sign_integrity(
+        &mut self,
+        mac_input: Vec<u8>,
+    ) -> Result<(RootKeyHistoryId, Vec<u8>), Error> {
+        let Unsealed {
+            root_key,
+            root_key_history_id,
+        } = Self::expect_unsealed(&mut self.state)?;
+
+        let mut hmac = root_key.0.read_inline(|k| {
+            HmacSha256::new_from_slice(k)
+                .unwrap_or_else(|_| unreachable!("HMAC accepts keys of any size"))
+        });
+        hmac.update(&root_key_history_id.to_raw().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: RootKeyHistoryId,
+    ) -> 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| {
+            HmacSha256::new_from_slice(k)
+                .unwrap_or_else(|_| unreachable!("HMAC accepts keys of any size"))
+        });
+        hmac.update(&key_version.to_raw().to_be_bytes());
+        hmac.update(&mac_input);
+
+        Ok(hmac.verify_slice(&expected_mac).is_ok())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::actors::GlobalActors;
+    use arbiter_crypto::safecell::SafeCellHandle as _;
+
+    use super::*;
+
+    async fn bootstrapped_actor(db: &db::DatabasePool) -> Vault {
+        let mut actor = Vault::new(db.clone(), GlobalActors::spawn_message_bus())
+            .await
+            .unwrap();
+        actor.bootstrap(KeyCell::from([0u8; 32])).await.unwrap();
+        actor
+    }
+
+    #[tokio::test]
+    #[test_log::test]
+    async fn nonce_monotonic_even_when_nonce_allocation_interleaves() {
+        let db = db::create_test_pool().await;
+        let mut actor = bootstrapped_actor(&db).await;
+        let State::Unsealed(Unsealed {
+            root_key_history_id,
+            ..
+        }) = actor.state
+        else {
+            panic!("expected unsealed state");
+        };
+
+        let n1 = Vault::get_new_nonce(&db, root_key_history_id)
+            .await
+            .unwrap();
+        let n2 = Vault::get_new_nonce(&db, root_key_history_id)
+            .await
+            .unwrap();
+        assert!(n2.to_vec() > n1.to_vec(), "nonce must increase");
+
+        let mut conn = db.get().await.unwrap();
+        let root_row: RootKeyHistory = schema::root_key_history::table
+            .select(RootKeyHistory::as_select())
+            .first(&mut conn)
+            .await
+            .unwrap();
+        assert_eq!(root_row.data_encryption_nonce, n2.to_vec());
+
+        let id = actor
+            .create_new(SafeCell::new(b"post-interleave".to_vec()))
+            .await
+            .unwrap();
+        let row: models::AeadEncrypted = schema::aead_encrypted::table
+            .filter(schema::aead_encrypted::id.eq(id))
+            .select(models::AeadEncrypted::as_select())
+            .first(&mut conn)
+            .await
+            .unwrap();
+        assert!(
+            row.current_nonce > n2.to_vec(),
+            "next write must advance nonce"
+        );
+    }
+}

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

@@ -0,0 +1,721 @@
+use std::collections::HashMap;
+
+use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
+use diesel::{ExpressionMethods as _, QueryDsl};
+use diesel_async::RunQueryDsl;
+use kameo::{Actor, actor::ActorRef, messages};
+use rand_core::{OsRng, RngCore as _};
+use tracing::error;
+
+use crate::{
+    actors::vault::{Bootstrap, RekeyRootKey, TryUnseal, Vault},
+    crypto::{KeyCell, derive_key, encryption::v1::Nonce, shamir, shamir::shamir_threshold},
+    db::{self, models, schema},
+};
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("Already coordinating a bootstrap")]
+    AlreadyBootstrapping,
+    #[error("Already coordinating an unseal")]
+    AlreadyUnsealing,
+    #[error("Rekey not in progress")]
+    NotRekeying,
+    #[error("Bootstrap not in progress")]
+    NotBootstrapping,
+    #[error("Unseal not in progress")]
+    NotUnsealing,
+    #[error("Operator already contributed")]
+    DuplicateContribution,
+    #[error("Operator not found in database")]
+    OperatorNotFound,
+    #[error("Invalid passphrase (decryption failed)")]
+    InvalidPassphrase,
+    #[error("Shamir error: {0}")]
+    Shamir(String),
+    #[error("Database connection error: {0}")]
+    DatabaseConnection(#[from] db::PoolError),
+    #[error("Database query error: {0}")]
+    DatabaseQuery(#[from] diesel::result::Error),
+    #[error("Encryption error")]
+    Encryption,
+    #[error("Vault error")]
+    VaultError,
+    #[error("Two-operator vaults require at least one recovery share")]
+    TwoOperatorsRequireRecovery,
+    #[error("Broken database")]
+    BrokenDatabase,
+}
+
+// Passphrases stored as plain Vec<u8> (not SafeCell) so CoordinatorState is Sync.
+// They are ephemeral and dropped immediately after use.
+enum CoordinatorState {
+    Idle,
+    Bootstrapping {
+        declared_count: usize,
+        recovery_count: usize,
+        passphrases: HashMap<i32, Vec<u8>>,
+        recovery_passphrases: HashMap<i32, Vec<u8>>,
+    },
+    Unsealing {
+        threshold: usize,
+        ordinary_passphrases: HashMap<i32, Vec<u8>>,
+        recovery_passphrases: HashMap<i32, Vec<u8>>,
+    },
+    /// Shamir re-key after `replace_operator` or `update_shamir_parameters` is approved (§3.3).
+    /// Collects new passphrases from all current operators, then generates a fresh seal key,
+    /// re-splits it, and re-encrypts the vault root key.
+    Rekeying {
+        ordinary_count: usize,
+        recovery_count: usize,
+        passphrases: HashMap<i32, Vec<u8>>,
+        recovery_passphrases: HashMap<i32, Vec<u8>>,
+    },
+}
+
+#[derive(Actor)]
+pub struct VaultCoordinator {
+    db: db::DatabasePool,
+    vault: ActorRef<Vault>,
+    state: CoordinatorState,
+}
+
+impl VaultCoordinator {
+    pub const fn new(db: db::DatabasePool, vault: ActorRef<Vault>) -> Self {
+        Self {
+            db,
+            vault,
+            state: CoordinatorState::Idle,
+        }
+    }
+}
+
+const SHARE_AAD: &[u8] = b"arbiter/shamir-share/v1";
+
+fn encrypt_share(
+    passphrase_bytes: Vec<u8>,
+    share: &[u8],
+) -> Result<(Vec<u8>, Vec<u8>, Vec<u8>), Error> {
+    let mut share_salt = vec![0u8; 32];
+    OsRng.fill_bytes(&mut share_salt);
+
+    let mut passphrase_cell = SafeCell::new(passphrase_bytes);
+    let mut share_seal_key = derive_key(&mut passphrase_cell, &share_salt);
+
+    let nonce = Nonce::default();
+    let encrypted_share = share_seal_key
+        .encrypt(&nonce, SHARE_AAD, share)
+        .map_err(|_| Error::Encryption)?;
+
+    Ok((encrypted_share, nonce.to_vec(), share_salt))
+}
+
+fn decrypt_share(
+    passphrase_bytes: Vec<u8>,
+    encrypted_share: Vec<u8>,
+    share_nonce_bytes: &[u8],
+    share_salt: &[u8],
+    operator_id: i32,
+) -> Result<Vec<u8>, Error> {
+    let nonce = Nonce::try_from(share_nonce_bytes).map_err(|()| {
+        error!(operator_id, "Invalid nonce in DB");
+        Error::BrokenDatabase
+    })?;
+
+    let mut passphrase_cell = SafeCell::new(passphrase_bytes);
+    let mut share_seal_key = derive_key(&mut passphrase_cell, share_salt);
+
+    let mut share_buffer = SafeCell::new(encrypted_share);
+    share_seal_key
+        .decrypt_in_place(&nonce, SHARE_AAD, &mut share_buffer)
+        .map_err(|_| Error::InvalidPassphrase)?;
+
+    Ok(share_buffer.read().clone())
+}
+
+/// §3.4: Split the seal key across ordinary + recovery operators.
+/// Threshold = `shamir_threshold(ordinary_count)`; total shares = ordinary + recovery.
+/// When `ordinary_count` == 1 (threshold = 1), vsss-rs does not support a proper split,
+/// so each share is the seal key itself — any single participant can reconstruct.
+async fn finalize_bootstrap(
+    db: db::DatabasePool,
+    vault: ActorRef<Vault>,
+    ordinary_passphrases: HashMap<i32, Vec<u8>>,
+    recovery_passphrases: HashMap<i32, Vec<u8>>,
+) -> Result<(), Error> {
+    let ordinary_count = ordinary_passphrases.len();
+    let recovery_count = recovery_passphrases.len();
+    let total = ordinary_count + recovery_count;
+    let threshold = shamir_threshold(ordinary_count);
+
+    let mut seal_key_bytes = [0u8; 32];
+    OsRng.fill_bytes(&mut seal_key_bytes);
+
+    // threshold == 1 means any single share reconstructs the key (degenerate split).
+    // vsss-rs requires threshold >= 2, so we store the key directly in this case.
+    let shares: Vec<Vec<u8>> = if threshold >= 2 {
+        shamir::split_key(threshold, total, &seal_key_bytes, OsRng)
+            .map_err(|e| Error::Shamir(e.to_string()))?
+    } else {
+        std::iter::repeat_with(|| seal_key_bytes.to_vec()).take(total).collect()
+    };
+
+    let seal_key = KeyCell::from(seal_key_bytes);
+
+    let mut conn = db.get().await?;
+    let mut shares_iter = shares.into_iter();
+
+    for (operator_id_raw, passphrase_bytes) in ordinary_passphrases {
+        let share = shares_iter
+            .next()
+            .expect("split_key returned enough shares");
+        let (encrypted_share, nonce_bytes, share_salt) = encrypt_share(passphrase_bytes, &share)?;
+
+        diesel::replace_into(schema::operator::table)
+            .values((
+                schema::operator::id.eq(Some(operator_id_raw)),
+                schema::operator::share.eq(&encrypted_share),
+                schema::operator::share_nonce.eq(&nonce_bytes),
+                schema::operator::share_salt.eq(&share_salt),
+                schema::operator::created_at.eq(models::SqliteTimestamp::now()),
+                schema::operator::updated_at.eq(models::SqliteTimestamp::now()),
+            ))
+            .execute(&mut conn)
+            .await?;
+    }
+
+    for (recovery_id_raw, passphrase_bytes) in recovery_passphrases {
+        let share = shares_iter
+            .next()
+            .expect("split_key returned enough shares");
+        let (encrypted_share, nonce_bytes, share_salt) = encrypt_share(passphrase_bytes, &share)?;
+
+        diesel::replace_into(schema::recovery_operator::table)
+            .values((
+                schema::recovery_operator::id.eq(recovery_id_raw),
+                schema::recovery_operator::share.eq(&encrypted_share),
+                schema::recovery_operator::share_nonce.eq(&nonce_bytes),
+                schema::recovery_operator::share_salt.eq(&share_salt),
+                schema::recovery_operator::created_at.eq(models::SqliteTimestamp::now()),
+                schema::recovery_operator::updated_at.eq(models::SqliteTimestamp::now()),
+            ))
+            .execute(&mut conn)
+            .await?;
+    }
+
+    vault.ask(Bootstrap { seal_key }).await.map_err(|err| {
+        error!(?err, "Vault bootstrap failed");
+        Error::VaultError
+    })?;
+
+    Ok(())
+}
+
+/// §3.5: Unseal using any threshold-sized mix of ordinary + recovery shares.
+async fn finalize_unseal(
+    db: db::DatabasePool,
+    vault: ActorRef<Vault>,
+    ordinary_passphrases: HashMap<i32, Vec<u8>>,
+    recovery_passphrases: HashMap<i32, Vec<u8>>,
+) -> Result<(), Error> {
+    let mut conn = db.get().await?;
+
+    // Determine whether shares were stored as raw keys (threshold=1) or vsss-rs splits (threshold>=2).
+    let ordinary_operator_count: i64 = schema::operator::table
+        .count()
+        .get_result(&mut conn)
+        .await?;
+    let threshold = shamir_threshold(ordinary_operator_count as usize);
+
+    let mut shares: Vec<Vec<u8>> = Vec::new();
+
+    for (operator_id_raw, passphrase_bytes) in ordinary_passphrases {
+        let (encrypted_share, share_nonce_bytes, share_salt): (Vec<u8>, Vec<u8>, Vec<u8>) =
+            schema::operator::table
+                .filter(schema::operator::id.eq(Some(operator_id_raw)))
+                .select((
+                    schema::operator::share,
+                    schema::operator::share_nonce,
+                    schema::operator::share_salt,
+                ))
+                .first(&mut conn)
+                .await
+                .map_err(|_| Error::OperatorNotFound)?;
+
+        shares.push(decrypt_share(
+            passphrase_bytes,
+            encrypted_share,
+            &share_nonce_bytes,
+            &share_salt,
+            operator_id_raw,
+        )?);
+    }
+
+    for (recovery_id_raw, passphrase_bytes) in recovery_passphrases {
+        let (encrypted_share, share_nonce_bytes, share_salt): (Vec<u8>, Vec<u8>, Vec<u8>) =
+            schema::recovery_operator::table
+                .find(recovery_id_raw)
+                .select((
+                    schema::recovery_operator::share,
+                    schema::recovery_operator::share_nonce,
+                    schema::recovery_operator::share_salt,
+                ))
+                .first(&mut conn)
+                .await
+                .map_err(|_| Error::OperatorNotFound)?;
+
+        shares.push(decrypt_share(
+            passphrase_bytes,
+            encrypted_share,
+            &share_nonce_bytes,
+            &share_salt,
+            recovery_id_raw,
+        )?);
+    }
+
+    // When threshold==1, shares are raw 32-byte seal keys (vsss-rs cannot split 1-of-N).
+    // Any single decrypted share is the key itself.
+    let seal_key_bytes: [u8; 32] = if threshold <= 1 {
+        let raw = shares
+            .into_iter()
+            .next()
+            .ok_or_else(|| Error::Shamir("No shares available".into()))?;
+        raw.try_into()
+            .map_err(|_| Error::Shamir("Invalid share length".into()))?
+    } else {
+        shamir::combine_shares(&shares).map_err(|e| Error::Shamir(e.to_string()))?
+    };
+
+    let seal_key = KeyCell::from(seal_key_bytes);
+
+    vault.ask(TryUnseal { seal_key }).await.map_err(|err| {
+        error!(?err, "Vault unseal failed");
+        Error::VaultError
+    })?;
+
+    Ok(())
+}
+
+/// §3.3: Generate a fresh seal key, split across current operators, re-encrypt the vault root key.
+/// Called after `replace_operator` or `update_shamir_parameters` is approved and all contributors submit.
+async fn finalize_rekey(
+    db: db::DatabasePool,
+    vault: ActorRef<Vault>,
+    ordinary_passphrases: HashMap<i32, Vec<u8>>,
+    recovery_passphrases: HashMap<i32, Vec<u8>>,
+) -> Result<(), Error> {
+    let ordinary_count = ordinary_passphrases.len();
+    let recovery_count = recovery_passphrases.len();
+    let total = ordinary_count + recovery_count;
+    let threshold = shamir_threshold(ordinary_count);
+
+    let mut new_seal_key_bytes = [0u8; 32];
+    OsRng.fill_bytes(&mut new_seal_key_bytes);
+
+    let shares: Vec<Vec<u8>> = if threshold >= 2 {
+        shamir::split_key(threshold, total, &new_seal_key_bytes, OsRng)
+            .map_err(|e| Error::Shamir(e.to_string()))?
+    } else {
+        std::iter::repeat_with(|| new_seal_key_bytes.to_vec())
+            .take(total)
+            .collect()
+    };
+
+    let mut conn = db.get().await?;
+    let mut shares_iter = shares.into_iter();
+
+    for (operator_id_raw, passphrase_bytes) in ordinary_passphrases {
+        let share = shares_iter
+            .next()
+            .expect("split_key returned enough shares");
+        let (encrypted_share, nonce_bytes, share_salt) = encrypt_share(passphrase_bytes, &share)?;
+
+        diesel::replace_into(schema::operator::table)
+            .values((
+                schema::operator::id.eq(Some(operator_id_raw)),
+                schema::operator::share.eq(&encrypted_share),
+                schema::operator::share_nonce.eq(&nonce_bytes),
+                schema::operator::share_salt.eq(&share_salt),
+                schema::operator::created_at.eq(models::SqliteTimestamp::now()),
+                schema::operator::updated_at.eq(models::SqliteTimestamp::now()),
+            ))
+            .execute(&mut conn)
+            .await?;
+    }
+
+    for (recovery_id_raw, passphrase_bytes) in recovery_passphrases {
+        let share = shares_iter
+            .next()
+            .expect("split_key returned enough shares");
+        let (encrypted_share, nonce_bytes, share_salt) = encrypt_share(passphrase_bytes, &share)?;
+
+        diesel::replace_into(schema::recovery_operator::table)
+            .values((
+                schema::recovery_operator::id.eq(recovery_id_raw),
+                schema::recovery_operator::share.eq(&encrypted_share),
+                schema::recovery_operator::share_nonce.eq(&nonce_bytes),
+                schema::recovery_operator::share_salt.eq(&share_salt),
+                schema::recovery_operator::created_at.eq(models::SqliteTimestamp::now()),
+                schema::recovery_operator::updated_at.eq(models::SqliteTimestamp::now()),
+            ))
+            .execute(&mut conn)
+            .await?;
+    }
+
+    drop(conn);
+
+    let new_seal_key = KeyCell::from(new_seal_key_bytes);
+    vault
+        .ask(RekeyRootKey { new_seal_key })
+        .await
+        .map_err(|err| {
+            error!(?err, "Vault rekey failed");
+            Error::VaultError
+        })?;
+
+    Ok(())
+}
+
+#[messages]
+impl VaultCoordinator {
+    /// Phase 1 of multi-operator bootstrap: declare the committee size.
+    #[message]
+    #[expect(clippy::unused_async, reason = "kameo requires messages to be async")]
+    pub async fn start_bootstrap(
+        &mut self,
+        operator_id: i32,
+        declared_count: usize,
+        recovery_count: usize,
+    ) -> Result<(), Error> {
+        let _ = operator_id; // fixme!: any authenticated operator may announce the committee size. the first call wins
+        if !matches!(self.state, CoordinatorState::Idle) {
+            return Err(Error::AlreadyBootstrapping);
+        }
+        if declared_count == 2 && recovery_count == 0 {
+            return Err(Error::TwoOperatorsRequireRecovery);
+        }
+        self.state = CoordinatorState::Bootstrapping {
+            declared_count,
+            recovery_count,
+            passphrases: HashMap::new(),
+            recovery_passphrases: HashMap::new(),
+        };
+        Ok(())
+    }
+
+    /// Phase 2 of multi-operator bootstrap: ordinary operator contributes a passphrase.
+    /// Returns Ok(true) when all ordinary + recovery operators contributed and bootstrap finalized.
+    #[message]
+    pub async fn contribute_bootstrap(
+        &mut self,
+        operator_id: i32,
+        mut passphrase: SafeCell<Vec<u8>>,
+    ) -> Result<bool, Error> {
+        let CoordinatorState::Bootstrapping {
+            declared_count,
+            recovery_count,
+            passphrases,
+            recovery_passphrases,
+        } = &mut self.state
+        else {
+            return Err(Error::NotBootstrapping);
+        };
+
+        if passphrases.contains_key(&operator_id) {
+            return Err(Error::DuplicateContribution);
+        }
+
+        let passphrase_bytes = passphrase.read().to_vec();
+        passphrases.insert(operator_id, passphrase_bytes);
+
+        if passphrases.len() < *declared_count || recovery_passphrases.len() < *recovery_count {
+            return Ok(false);
+        }
+
+        let CoordinatorState::Bootstrapping {
+            passphrases,
+            recovery_passphrases,
+            ..
+        } = std::mem::replace(&mut self.state, CoordinatorState::Idle)
+        else {
+            unreachable!()
+        };
+
+        finalize_bootstrap(
+            self.db.clone(),
+            self.vault.clone(),
+            passphrases,
+            recovery_passphrases,
+        )
+        .await?;
+        Ok(true)
+    }
+
+    /// Phase 2 of multi-operator bootstrap: recovery operator contributes a passphrase.
+    /// Returns Ok(true) when all contributors are in and bootstrap finalized.
+    #[message]
+    pub async fn contribute_recovery_bootstrap(
+        &mut self,
+        recovery_operator_id: i32,
+        mut passphrase: SafeCell<Vec<u8>>,
+    ) -> Result<bool, Error> {
+        let CoordinatorState::Bootstrapping {
+            declared_count,
+            recovery_count,
+            passphrases,
+            recovery_passphrases,
+        } = &mut self.state
+        else {
+            return Err(Error::NotBootstrapping);
+        };
+
+        if recovery_passphrases.contains_key(&recovery_operator_id) {
+            return Err(Error::DuplicateContribution);
+        }
+
+        let passphrase_bytes = passphrase.read().to_vec();
+        recovery_passphrases.insert(recovery_operator_id, passphrase_bytes);
+
+        if passphrases.len() < *declared_count || recovery_passphrases.len() < *recovery_count {
+            return Ok(false);
+        }
+
+        let CoordinatorState::Bootstrapping {
+            passphrases,
+            recovery_passphrases,
+            ..
+        } = std::mem::replace(&mut self.state, CoordinatorState::Idle)
+        else {
+            unreachable!()
+        };
+
+        finalize_bootstrap(
+            self.db.clone(),
+            self.vault.clone(),
+            passphrases,
+            recovery_passphrases,
+        )
+        .await?;
+        Ok(true)
+    }
+
+    /// Contribute a passphrase for vault unseal (ordinary operator).
+    /// Returns Ok(true) when threshold reached and vault is unsealed.
+    #[message]
+    pub async fn contribute_unseal(
+        &mut self,
+        operator_id: i32,
+        mut passphrase: SafeCell<Vec<u8>>,
+    ) -> Result<bool, Error> {
+        self.ensure_unsealing_state().await?;
+
+        let CoordinatorState::Unsealing {
+            threshold,
+            ordinary_passphrases,
+            recovery_passphrases,
+        } = &mut self.state
+        else {
+            return Err(Error::NotUnsealing);
+        };
+
+        if ordinary_passphrases.contains_key(&operator_id) {
+            return Err(Error::DuplicateContribution);
+        }
+
+        let passphrase_bytes = passphrase.read().to_vec();
+        ordinary_passphrases.insert(operator_id, passphrase_bytes);
+
+        if ordinary_passphrases.len() + recovery_passphrases.len() < *threshold {
+            return Ok(false);
+        }
+
+        self.do_finalize_unseal().await
+    }
+
+    /// Contribute a passphrase for vault unseal (recovery operator, §3.5).
+    /// Recovery operators may contribute during unseal when recovery is active.
+    /// Returns Ok(true) when threshold reached and vault is unsealed.
+    #[message]
+    pub async fn contribute_recovery_unseal(
+        &mut self,
+        recovery_operator_id: i32,
+        mut passphrase: SafeCell<Vec<u8>>,
+    ) -> Result<bool, Error> {
+        self.ensure_unsealing_state().await?;
+
+        let CoordinatorState::Unsealing {
+            threshold,
+            ordinary_passphrases,
+            recovery_passphrases,
+        } = &mut self.state
+        else {
+            return Err(Error::NotUnsealing);
+        };
+
+        if recovery_passphrases.contains_key(&recovery_operator_id) {
+            return Err(Error::DuplicateContribution);
+        }
+
+        let passphrase_bytes = passphrase.read().to_vec();
+        recovery_passphrases.insert(recovery_operator_id, passphrase_bytes);
+
+        if ordinary_passphrases.len() + recovery_passphrases.len() < *threshold {
+            return Ok(false);
+        }
+
+        self.do_finalize_unseal().await
+    }
+}
+
+impl VaultCoordinator {
+    /// Initializes `CoordinatorState::Unsealing` on first call if still `Idle`.
+    /// Threshold is based on ordinary operator count only (§3.4).
+    async fn ensure_unsealing_state(&mut self) -> Result<(), Error> {
+        if matches!(self.state, CoordinatorState::Idle) {
+            let mut conn = self.db.get().await?;
+            let ordinary_count: i64 = schema::operator::table
+                .count()
+                .get_result(&mut conn)
+                .await?;
+            let threshold = shamir_threshold(usize::try_from(ordinary_count).unwrap_or_default());
+            self.state = CoordinatorState::Unsealing {
+                threshold,
+                ordinary_passphrases: HashMap::new(),
+                recovery_passphrases: HashMap::new(),
+            };
+        }
+        Ok(())
+    }
+
+    /// Moves state back to Idle and calls finalize_unseal.
+    async fn do_finalize_unseal(&mut self) -> Result<bool, Error> {
+        let CoordinatorState::Unsealing {
+            ordinary_passphrases,
+            recovery_passphrases,
+            ..
+        } = std::mem::replace(&mut self.state, CoordinatorState::Idle)
+        else {
+            unreachable!()
+        };
+
+        finalize_unseal(
+            self.db.clone(),
+            self.vault.clone(),
+            ordinary_passphrases,
+            recovery_passphrases,
+        )
+        .await?;
+        Ok(true)
+    }
+
+    async fn do_finalize_rekey(&mut self) -> Result<bool, Error> {
+        let CoordinatorState::Rekeying {
+            passphrases,
+            recovery_passphrases,
+            ..
+        } = std::mem::replace(&mut self.state, CoordinatorState::Idle)
+        else {
+            unreachable!()
+        };
+
+        finalize_rekey(
+            self.db.clone(),
+            self.vault.clone(),
+            passphrases,
+            recovery_passphrases,
+        )
+        .await?;
+        Ok(true)
+    }
+}
+
+#[messages]
+impl VaultCoordinator {
+    /// Begin Shamir re-key after a key-rotation proposal is approved (§3.3).
+    /// Queries the current operator and recovery operator counts from the DB,
+    /// then transitions to Rekeying state awaiting contributions from all of them.
+    #[message]
+    pub async fn start_rekey(&mut self) -> Result<(), Error> {
+        if !matches!(self.state, CoordinatorState::Idle) {
+            return Err(Error::AlreadyBootstrapping);
+        }
+        let mut conn = self.db.get().await?;
+        let ordinary_count: i64 = schema::operator_identity::table
+            .count()
+            .get_result(&mut conn)
+            .await?;
+        let recovery_count: i64 = schema::recovery_operator_identity::table
+            .count()
+            .get_result(&mut conn)
+            .await?;
+        self.state = CoordinatorState::Rekeying {
+            ordinary_count: ordinary_count as usize,
+            recovery_count: recovery_count as usize,
+            passphrases: HashMap::new(),
+            recovery_passphrases: HashMap::new(),
+        };
+        Ok(())
+    }
+
+    /// Contribute an ordinary operator passphrase for the re-key.
+    /// Returns Ok(true) when all contributors have submitted and the re-key is complete.
+    #[message]
+    pub async fn contribute_rekey(
+        &mut self,
+        operator_id: i32,
+        mut passphrase: SafeCell<Vec<u8>>,
+    ) -> Result<bool, Error> {
+        let CoordinatorState::Rekeying {
+            ordinary_count,
+            recovery_count,
+            passphrases,
+            recovery_passphrases,
+        } = &mut self.state
+        else {
+            return Err(Error::NotRekeying);
+        };
+
+        if passphrases.contains_key(&operator_id) {
+            return Err(Error::DuplicateContribution);
+        }
+
+        passphrases.insert(operator_id, passphrase.read().to_vec());
+
+        if passphrases.len() < *ordinary_count || recovery_passphrases.len() < *recovery_count {
+            return Ok(false);
+        }
+
+        self.do_finalize_rekey().await
+    }
+
+    /// Contribute a recovery operator passphrase for the re-key.
+    /// Returns Ok(true) when all contributors have submitted and the re-key is complete.
+    #[message]
+    pub async fn contribute_recovery_rekey(
+        &mut self,
+        recovery_operator_id: i32,
+        mut passphrase: SafeCell<Vec<u8>>,
+    ) -> Result<bool, Error> {
+        let CoordinatorState::Rekeying {
+            ordinary_count,
+            recovery_count,
+            passphrases,
+            recovery_passphrases,
+        } = &mut self.state
+        else {
+            return Err(Error::NotRekeying);
+        };
+
+        if recovery_passphrases.contains_key(&recovery_operator_id) {
+            return Err(Error::DuplicateContribution);
+        }
+
+        recovery_passphrases.insert(recovery_operator_id, passphrase.read().to_vec());
+
+        if passphrases.len() < *ordinary_count || recovery_passphrases.len() < *recovery_count {
+            return Ok(false);
+        }
+
+        self.do_finalize_rekey().await
+    }
+}

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

@@ -1,13 +1,12 @@
-use std::sync::Arc;
-
-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)]
@@ -25,7 +24,7 @@ pub enum InitError {
     Tls(#[from] tls::InitError),
 
     #[error("Actor spawn failed: {0}")]
-    ActorSpawn(#[from] crate::actors::GlobalActorsSpawnError),
+    ActorSpawn(#[from] crate::actors::SpawnError),
 
     #[error("I/O Error: {0}")]
     Io(#[from] std::io::Error),

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

@@ -1,17 +1,3 @@
-use std::{net::Ipv4Addr, string::FromUtf8Error};
-
-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 thiserror::Error;
-use tonic::transport::CertificateDer;
-
 use crate::db::{
     self,
     models::{NewTlsHistory, TlsHistory},
@@ -21,6 +7,18 @@ 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") {
         pem::LineEnding::CRLF
@@ -176,28 +174,26 @@ impl TlsManager {
 
         {
             let mut conn = db.get().await?;
-            conn.transaction(|conn| {
-                Box::pin(async {
-                    let new_tls_history = NewTlsHistory {
-                        cert: new_cert.cert.pem(),
-                        cert_key: new_cert.cert_key.serialize_pem(),
-                        ca_cert: encode_cert_to_pem(&ca.cert),
-                        ca_key: ca.issuer.key().serialize_pem(),
-                    };
+            conn.transaction(async |conn| {
+                let new_tls_history = NewTlsHistory {
+                    cert: new_cert.cert.pem(),
+                    cert_key: new_cert.cert_key.serialize_pem(),
+                    ca_cert: encode_cert_to_pem(&ca.cert),
+                    ca_key: ca.issuer.key().serialize_pem(),
+                };
 
-                    let inserted_tls_history: i32 = diesel::insert_into(tls_history::table)
-                        .values(&new_tls_history)
-                        .returning(tls_history::id)
-                        .get_result(conn)
-                        .await?;
+                let inserted_tls_history: i32 = diesel::insert_into(tls_history::table)
+                    .values(&new_tls_history)
+                    .returning(tls_history::id)
+                    .get_result(&mut *conn)
+                    .await?;
 
-                    diesel::update(arbiter_settings::table)
-                        .set(arbiter_settings::tls_id.eq(inserted_tls_history))
-                        .execute(conn)
-                        .await?;
+                diesel::update(arbiter_settings::table)
+                    .set(arbiter_settings::tls_id.eq(inserted_tls_history))
+                    .execute(&mut *conn)
+                    .await?;
 
-                    Result::<_, diesel::result::Error>::Ok(())
-                })
+                Result::<_, diesel::result::Error>::Ok(())
             })
             .await?;
         }

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

@@ -1,5 +1,4 @@
 use argon2::password_hash::Salt as ArgonSalt;
-
 use rand::{
     Rng as _, SeedableRng,
     rngs::{StdRng, SysRng},
@@ -60,14 +59,14 @@ mod tests {
     use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
 
     #[test]
-    pub fn derive_seal_key_deterministic() {
+    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 mut password = SafeCell::new(PASSWORD.to_vec());
+        let mut 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 mut key1 = derive_key(&mut password, &salt);
+        let mut key2 = derive_key(&mut password2, &salt);
 
         let key1_reader = key1.0.read();
         let key2_reader = key2.0.read();
@@ -76,12 +75,12 @@ mod tests {
     }
 
     #[test]
-    pub fn successful_derive() {
+    fn successful_derive() {
         static PASSWORD: &[u8] = b"password";
-        let password = SafeCell::new(PASSWORD.to_vec());
+        let mut password = SafeCell::new(PASSWORD.to_vec());
         let salt = generate_salt();
 
-        let mut key = derive_key(password, &salt);
+        let mut key = derive_key(&mut password, &salt);
         let key_reader = key.0.read();
 
         assert_ne!(key_reader.as_slice(), &[0u8; 32][..]);

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

@@ -1,32 +1,29 @@
-use crate::actors::keyholder;
-use arbiter_crypto::hashing::Hashable;
-use hmac::Hmac;
-use sha2::Sha256;
-
-use diesel::{ExpressionMethods as _, QueryDsl, dsl::insert_into, sqlite::Sqlite};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use kameo::{actor::ActorRef, error::SendError};
-use sha2::Digest as _;
-
 use crate::{
-    actors::keyholder::{KeyHolder, SignIntegrity, VerifyIntegrity},
+    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 IntegrityError {
+pub enum Error {
     #[error("Database error: {0}")]
     Database(#[from] db::DatabaseError),
 
-    #[error("KeyHolder error: {0}")]
-    Keyholder(#[from] keyholder::KeyHolderError),
+    #[error("Vault error: {0}")]
+    Vault(#[from] vault::Error),
 
-    #[error("KeyHolder mailbox error")]
-    KeyholderSend,
+    #[error("Vault mailbox error")]
+    VaultSend,
 
     #[error("Integrity envelope is missing for entity {entity_kind}")]
     MissingEnvelope { entity_kind: &'static str },
@@ -108,23 +105,24 @@ impl IntoId for &'_ [u8] {
 
 pub async fn sign_entity<E: Integrable>(
     conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    keyholder: &ActorRef<KeyHolder>,
+    vault: &ActorRef<Vault>,
     entity: &E,
     entity_id: impl IntoId,
-) -> Result<(), IntegrityError> {
+) -> 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) = keyholder
-        .ask(SignIntegrity { mac_input })
-        .await
-        .map_err(|err| match err {
-            SendError::HandlerError(inner) => IntegrityError::Keyholder(inner),
-            _ => IntegrityError::KeyholderSend,
-        })?;
+    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 {
@@ -153,10 +151,10 @@ pub async fn sign_entity<E: Integrable>(
 
 pub async fn verify_entity<E: Integrable>(
     conn: &mut impl AsyncConnection<Backend = Sqlite>,
-    keyholder: &ActorRef<KeyHolder>,
+    vault: &ActorRef<Vault>,
     entity: &E,
     entity_id: impl IntoId,
-) -> Result<AttestationStatus, IntegrityError> {
+) -> Result<AttestationStatus, Error> {
     let entity_id = entity_id.into_id();
     let envelope: IntegrityEnvelope = integrity_envelope::table
         .filter(integrity_envelope::entity_kind.eq(E::KIND))
@@ -164,14 +162,14 @@ pub async fn verify_entity<E: Integrable>(
         .first(conn)
         .await
         .map_err(|err| match err {
-            diesel::result::Error::NotFound => IntegrityError::MissingEnvelope {
+            diesel::result::Error::NotFound => Error::MissingEnvelope {
                 entity_kind: E::KIND,
             },
-            other => IntegrityError::Database(db::DatabaseError::from(other)),
+            other => Error::Database(db::DatabaseError::from(other)),
         })?;
 
     if envelope.payload_version != E::VERSION {
-        return Err(IntegrityError::PayloadVersionMismatch {
+        return Err(Error::PayloadVersionMismatch {
             entity_kind: E::KIND,
             expected: E::VERSION,
             found: envelope.payload_version,
@@ -181,7 +179,7 @@ pub async fn verify_entity<E: Integrable>(
     let payload_hash = payload_hash(&entity);
     let mac_input = build_mac_input(E::KIND, &entity_id, envelope.payload_version, &payload_hash);
 
-    let result = keyholder
+    let result = vault
         .ask(VerifyIntegrity {
             mac_input,
             expected_mac: envelope.mac,
@@ -191,16 +189,19 @@ pub async fn verify_entity<E: Integrable>(
 
     match result {
         Ok(true) => Ok(AttestationStatus::Attested),
-        Ok(false) => Err(IntegrityError::MacMismatch {
+        Ok(false) => Err(Error::MacMismatch {
             entity_kind: E::KIND,
         }),
-        Err(SendError::HandlerError(keyholder::KeyHolderError::NotBootstrapped)) => {
-            Ok(AttestationStatus::Unavailable)
-        }
-        Err(_) => Err(IntegrityError::KeyholderSend),
+        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};
@@ -208,12 +209,13 @@ mod tests {
     use kameo::{actor::ActorRef, prelude::Spawn};
 
     use crate::{
-        actors::keyholder::{Bootstrap, KeyHolder},
+        actors::{
+            GlobalActors,
+            vault::{Bootstrap, Vault},
+        },
         db::{self, schema},
     };
-    use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
-    use super::{Integrable, IntegrityError, sign_entity, verify_entity};
+    use super::{Error, Integrable, sign_entity, verify_entity};
     #[derive(Clone, arbiter_macros::Hashable)]
     struct DummyEntity {
         payload_version: i32,
@@ -223,11 +225,15 @@ mod tests {
         const KIND: &'static str = "dummy_entity";
     }
 
-    async fn bootstrapped_keyholder(db: &db::DatabasePool) -> ActorRef<KeyHolder> {
-        let actor = KeyHolder::spawn(KeyHolder::new(db.clone()).await.unwrap());
+    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()),
+                seal_key: crate::crypto::KeyCell::from([0u8; 32]),
             })
             .await
             .unwrap();
@@ -239,7 +245,7 @@ mod tests {
         const ENTITY_ID: &[u8] = b"entity-id-7";
 
         let db = db::create_test_pool().await;
-        let keyholder = bootstrapped_keyholder(&db).await;
+        let vault = bootstrapped_vault(&db).await;
         let mut conn = db.get().await.unwrap();
 
         let entity = DummyEntity {
@@ -247,7 +253,7 @@ mod tests {
             payload: b"payload-v1".to_vec(),
         };
 
-        sign_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
+        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
             .await
             .unwrap();
 
@@ -260,7 +266,7 @@ mod tests {
             .unwrap();
 
         assert_eq!(count, 1, "envelope row must be created exactly once");
-        verify_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
+        verify_entity(&mut conn, &vault, &entity, ENTITY_ID)
             .await
             .unwrap();
     }
@@ -270,7 +276,7 @@ mod tests {
         const ENTITY_ID: &[u8] = b"entity-id-11";
 
         let db = db::create_test_pool().await;
-        let keyholder = bootstrapped_keyholder(&db).await;
+        let vault = bootstrapped_vault(&db).await;
         let mut conn = db.get().await.unwrap();
 
         let entity = DummyEntity {
@@ -278,7 +284,7 @@ mod tests {
             payload: b"payload-v1".to_vec(),
         };
 
-        sign_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
+        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
             .await
             .unwrap();
 
@@ -290,10 +296,10 @@ mod tests {
             .await
             .unwrap();
 
-        let err = verify_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
+        let err = verify_entity(&mut conn, &vault, &entity, ENTITY_ID)
             .await
             .unwrap_err();
-        assert!(matches!(err, IntegrityError::MacMismatch { .. }));
+        assert!(matches!(err, Error::MacMismatch { .. }));
     }
 
     #[tokio::test]
@@ -301,7 +307,7 @@ mod tests {
         const ENTITY_ID: &[u8] = b"entity-id-21";
 
         let db = db::create_test_pool().await;
-        let keyholder = bootstrapped_keyholder(&db).await;
+        let vault = bootstrapped_vault(&db).await;
         let mut conn = db.get().await.unwrap();
 
         let entity = DummyEntity {
@@ -309,7 +315,7 @@ mod tests {
             payload: b"payload-v1".to_vec(),
         };
 
-        sign_entity(&mut conn, &keyholder, &entity, ENTITY_ID)
+        sign_entity(&mut conn, &vault, &entity, ENTITY_ID)
             .await
             .unwrap();
 
@@ -318,9 +324,9 @@ mod tests {
             ..entity
         };
 
-        let err = verify_entity(&mut conn, &keyholder, &tampered, ENTITY_ID)
+        let err = verify_entity(&mut conn, &vault, &tampered, ENTITY_ID)
             .await
             .unwrap_err();
-        assert!(matches!(err, IntegrityError::MacMismatch { .. }));
+        assert!(matches!(err, Error::MacMismatch { .. }));
     }
 }

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

@@ -1,3 +1,6 @@
+use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
+use encryption::v1::Nonce;
+
 use argon2::{Algorithm, Argon2};
 use chacha20poly1305::{
     AeadInPlace, Key, KeyInit as _, XChaCha20Poly1305, XNonce,
@@ -8,12 +11,9 @@ use rand::{
     rngs::{StdRng, SysRng},
 };
 
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
-
 pub mod encryption;
 pub mod integrity;
-
-use encryption::v1::{Nonce, Salt};
+pub mod shamir;
 
 pub struct KeyCell(pub SafeCell<Key>);
 impl From<SafeCell<Key>> for KeyCell {
@@ -21,6 +21,15 @@ impl From<SafeCell<Key>> for KeyCell {
         Self(value)
     }
 }
+impl From<[u8; 32]> for KeyCell {
+    fn from(bytes: [u8; 32]) -> Self {
+        let cell = SafeCell::new_inline_default(|key: &mut Key| {
+            key.copy_from_slice(&bytes);
+        });
+        Self(cell)
+    }
+}
+
 impl TryFrom<SafeCell<Vec<u8>>> for KeyCell {
     type Error = ();
 
@@ -29,7 +38,7 @@ impl TryFrom<SafeCell<Vec<u8>>> for KeyCell {
         if value.len() != size_of::<Key>() {
             return Err(());
         }
-        let cell = SafeCell::new_inline(|cell_write: &mut Key| {
+        let cell = SafeCell::new_inline_default(|cell_write: &mut Key| {
             cell_write.copy_from_slice(&value);
         });
         Ok(Self(cell))
@@ -38,7 +47,7 @@ impl TryFrom<SafeCell<Vec<u8>>> for KeyCell {
 
 impl KeyCell {
     pub fn new_secure_random() -> Self {
-        let key = SafeCell::new_inline(|key_buffer: &mut Key| {
+        let key = SafeCell::new_inline_default(|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);
@@ -95,7 +104,7 @@ impl KeyCell {
 }
 
 /// 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 {
+pub fn derive_key(password: &mut SafeCell<Vec<u8>>, salt: &[u8]) -> KeyCell {
     let params = {
         #[cfg(debug_assertions)]
         {
@@ -131,12 +140,12 @@ mod tests {
     use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
 
     #[test]
-    pub fn encrypt_decrypt() {
+    fn encrypt_decrypt() {
         static PASSWORD: &[u8] = b"password";
-        let password = SafeCell::new(PASSWORD.to_vec());
+        let mut password = SafeCell::new(PASSWORD.to_vec());
         let salt = generate_salt();
 
-        let mut key = derive_key(password, &salt);
+        let mut key = derive_key(&mut 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();

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

@@ -0,0 +1,41 @@
+use vsss_rs::Gf256;
+
+#[derive(Debug, thiserror::Error)]
+pub enum ShamirError {
+    #[error("Failed to split key: {0}")]
+    Split(String),
+    #[error("Failed to combine shares: {0}")]
+    Combine(String),
+}
+
+/// Split `key` into `total` shares where any `threshold` shares can reconstruct it.
+/// Each returned Vec<u8> is a share with format [`identifier_byte`, `value_bytes`...].
+pub fn split_key(
+    threshold: usize,
+    total: usize,
+    key: &[u8; 32],
+    rng: impl rand_core::RngCore + rand_core::CryptoRng,
+) -> Result<Vec<Vec<u8>>, ShamirError> {
+    Gf256::split_array(threshold, total, key.as_slice(), rng)
+        .map_err(|e| ShamirError::Split(format!("{e:?}")))
+}
+
+/// Returns the minimum number of shares required to reconstruct the secret
+/// for a committee of `n` operators.
+#[must_use]
+pub const fn shamir_threshold(n: usize) -> usize {
+    match n {
+        0 => panic!("No operators"),
+        1 => 1,
+        2 => 2,
+        n => n / 2 + 1,
+    }
+}
+
+/// Reconstruct the secret from `threshold` or more shares.
+pub fn combine_shares(shares: &[Vec<u8>]) -> Result<[u8; 32], ShamirError> {
+    let bytes = Gf256::combine_array(shares)
+        .map_err(|e| ShamirError::Combine(format!("{e:?}")))?;
+    <[u8; 32]>::try_from(bytes.as_slice())
+        .map_err(|_| ShamirError::Combine("unexpected reconstructed key length".to_owned()))
+}

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

@@ -5,7 +5,6 @@ use diesel_async::{
     sync_connection_wrapper::SyncConnectionWrapper,
 };
 use diesel_migrations::{EmbeddedMigrations, MigrationHarness, embed_migrations};
-
 use thiserror::Error;
 use tracing::info;
 

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

@@ -2,23 +2,24 @@
     clippy::duplicated_attributes,
     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,
 };
+
 use diesel::{prelude::*, sqlite::Sqlite};
 use restructed::Models;
 
 pub mod types {
     use chrono::{DateTime, Utc};
     use diesel::{
+        backend::Backend,
         deserialize::{FromSql, FromSqlRow},
         expression::AsExpression,
         serialize::{IsNull, ToSql},
-        sql_types::Integer,
+        sql_types::{Integer, Text},
         sqlite::{Sqlite, SqliteType},
     };
 
@@ -61,7 +62,7 @@ pub mod types {
 
     impl FromSql<Integer, Sqlite> for SqliteTimestamp {
         fn from_sql(
-            mut bytes: <Sqlite as diesel::backend::Backend>::RawValue<'_>,
+            mut bytes: <Sqlite as Backend>::RawValue<'_>,
         ) -> diesel::deserialize::Result<Self> {
             let Some(SqliteType::Long) = bytes.value_type() else {
                 return Err(format!(
@@ -79,10 +80,41 @@ pub mod types {
         }
     }
 
-    #[derive(Debug, FromSqlRow, AsExpression, Clone)]
-    #[diesel(sql_type = Integer)]
-    #[repr(transparent)] // hint compiler to optimize the wrapper struct away
-    pub struct ChainId(pub i32);
+    macro_rules! declare_id {
+        ($name:ident) => {
+            #[derive(Debug, FromSqlRow, AsExpression, Clone, Hash, Copy, PartialEq, Eq)]
+            #[diesel(sql_type = Integer)]
+            #[repr(transparent)] // hint compiler to optimize the wrapper struct away
+            pub struct $name(i32);
+
+            impl $name {
+                pub const fn to_raw(self) -> i32 {
+                    self.0
+                }
+                pub const fn from_raw(raw: i32) -> Self {
+                    Self(raw)
+                }
+            }
+
+            impl FromSql<Integer, Sqlite> for $name {
+                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 $name {
+                fn to_sql<'b>(
+                    &'b self,
+                    out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
+                ) -> diesel::serialize::Result {
+                    ToSql::<Integer, Sqlite>::to_sql(&self.0, out)
+                }
+            }
+        };
+    }
+
+    declare_id!(ChainId);
 
     #[expect(
         clippy::cast_sign_loss,
@@ -103,19 +135,50 @@ pub mod types {
         }
     };
 
-    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)
-        }
+    declare_id!(OperatorId);
+    declare_id!(OperatorIdentityId);
+    declare_id!(AeadEncryptedId);
+    declare_id!(RootKeyHistoryId);
+    declare_id!(TlsHistoryId);
+    declare_id!(EvmWalletId);
+    declare_id!(ClientId);
+
+    #[derive(Debug, Clone, PartialEq, Eq, AsExpression, FromSqlRow)]
+    #[diesel(sql_type = Text)]
+    pub enum ProposalStatus {
+        Pending,
+        Approved,
+        Rejected,
+        Expired,
     }
-    impl ToSql<Integer, Sqlite> for ChainId {
+
+    impl ToSql<Text, Sqlite> for ProposalStatus {
         fn to_sql<'b>(
             &'b self,
             out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
         ) -> diesel::serialize::Result {
-            ToSql::<Integer, Sqlite>::to_sql(&self.0, out)
+            let s: &str = match self {
+                Self::Pending => "pending",
+                Self::Approved => "approved",
+                Self::Rejected => "rejected",
+                Self::Expired => "expired",
+            };
+            <str as ToSql<Text, Sqlite>>::to_sql(s, out)
+        }
+    }
+
+    impl FromSql<Text, Sqlite> for ProposalStatus {
+        fn from_sql(
+            bytes: <Sqlite as Backend>::RawValue<'_>,
+        ) -> diesel::deserialize::Result<Self> {
+            let s = <String as FromSql<Text, Sqlite>>::from_sql(bytes)?;
+            match s.as_str() {
+                "pending" => Ok(Self::Pending),
+                "approved" => Ok(Self::Approved),
+                "rejected" => Ok(Self::Rejected),
+                "expired" => Ok(Self::Expired),
+                other => Err(format!("Unknown proposal status: {other}").into()),
+            }
         }
     }
 }
@@ -130,12 +193,12 @@ pub use types::*;
 )]
 #[diesel(table_name = aead_encrypted, check_for_backend(Sqlite))]
 pub struct AeadEncrypted {
-    pub id: i32,
+    pub id: AeadEncryptedId,
     pub ciphertext: Vec<u8>,
     pub tag: Vec<u8>,
     pub current_nonce: Vec<u8>,
     pub schema_version: i32,
-    pub associated_root_key_id: i32, // references root_key_history.id
+    pub associated_root_key_id: RootKeyHistoryId,
     pub created_at: SqliteTimestamp,
 }
 
@@ -148,7 +211,7 @@ pub struct AeadEncrypted {
     attributes_with = "deriveless"
 )]
 pub struct RootKeyHistory {
-    pub id: i32,
+    pub id: RootKeyHistoryId,
     pub ciphertext: Vec<u8>,
     pub tag: Vec<u8>,
     pub root_key_encryption_nonce: Vec<u8>,
@@ -166,7 +229,7 @@ pub struct RootKeyHistory {
     attributes_with = "deriveless"
 )]
 pub struct TlsHistory {
-    pub id: i32,
+    pub id: TlsHistoryId,
     pub cert: String,
     pub cert_key: String, // PEM Encoded private key
     pub ca_cert: String,  // PEM Encoded certificate for cert signing
@@ -191,7 +254,7 @@ pub struct ArbiterSettings {
     attributes_with = "deriveless"
 )]
 pub struct EvmWallet {
-    pub id: i32,
+    pub id: EvmWalletId,
     pub address: Vec<u8>,
     pub aead_encrypted_id: i32,
     pub created_at: SqliteTimestamp,
@@ -213,7 +276,7 @@ pub struct EvmWallet {
 )]
 pub struct EvmWalletAccess {
     pub id: i32,
-    pub wallet_id: i32,
+    pub wallet_id: EvmWalletId,
     pub client_id: i32,
     pub created_at: SqliteTimestamp,
 }
@@ -240,8 +303,7 @@ pub struct ProgramClientMetadataHistory {
 #[derive(Models, Queryable, Debug, Insertable, Selectable)]
 #[diesel(table_name = schema::program_client, check_for_backend(Sqlite))]
 pub struct ProgramClient {
-    pub id: i32,
-    pub nonce: i32,
+    pub id: ClientId,
     pub public_key: Vec<u8>,
     pub metadata_id: i32,
     pub created_at: SqliteTimestamp,
@@ -249,15 +311,25 @@ pub struct ProgramClient {
 }
 
 #[derive(Queryable, Debug)]
-#[diesel(table_name = schema::useragent_client, check_for_backend(Sqlite))]
-pub struct UseragentClient {
-    pub id: i32,
-    pub nonce: i32,
+#[diesel(table_name = schema::operator_client, check_for_backend(Sqlite))]
+pub struct OperatorClient {
+    pub id: OperatorIdentityId,
     pub public_key: Vec<u8>,
     pub created_at: SqliteTimestamp,
     pub updated_at: SqliteTimestamp,
 }
 
+#[derive(Queryable, Debug)]
+#[diesel(table_name = schema::operator, check_for_backend(Sqlite))]
+pub struct Operator {
+    pub id: OperatorId,
+    pub share: Vec<u8>,
+    pub share_nonce: Vec<u8>,
+    pub share_salt: Vec<u8>,
+    pub created_at: SqliteTimestamp,
+    pub updated_at: SqliteTimestamp,
+}
+
 #[derive(Models, Queryable, Debug, Insertable, Selectable)]
 #[diesel(table_name = evm_ether_transfer_limit, check_for_backend(Sqlite))]
 #[view(
@@ -401,8 +473,73 @@ pub struct IntegrityEnvelope {
     pub entity_kind: String,
     pub entity_id: Vec<u8>,
     pub payload_version: i32,
-    pub key_version: i32,
+    pub key_version: RootKeyHistoryId,
     pub mac: Vec<u8>,
     pub signed_at: SqliteTimestamp,
     pub created_at: SqliteTimestamp,
 }
+
+#[derive(Debug, Queryable, Selectable, Identifiable)]
+#[diesel(table_name = schema::proposal, check_for_backend(Sqlite))]
+pub struct Proposal {
+    pub id: i32,
+    pub kind: String,
+    pub payload: Vec<u8>,
+    pub initiator_id: i32,
+    pub created_at: SqliteTimestamp,
+    pub expires_at: SqliteTimestamp,
+    pub status: ProposalStatus,
+}
+
+#[derive(Debug, Insertable)]
+#[diesel(table_name = schema::proposal, check_for_backend(Sqlite))]
+pub struct NewProposal {
+    pub kind: String,
+    pub payload: Vec<u8>,
+    pub initiator_id: i32,
+    // status defaults to 'pending' at the DB layer
+    pub expires_at: SqliteTimestamp,
+}
+
+#[derive(Debug, Queryable, Selectable, Identifiable)]
+#[diesel(table_name = schema::proposal_vote, check_for_backend(Sqlite))]
+pub struct ProposalVote {
+    pub id: i32,
+    pub proposal_id: i32,
+    pub operator_id: i32,
+    pub approve: bool,
+    pub signature: Vec<u8>,
+    pub voted_at: SqliteTimestamp,
+}
+
+#[derive(Debug, Insertable)]
+#[diesel(table_name = schema::proposal_vote, check_for_backend(Sqlite))]
+pub struct NewProposalVote {
+    pub proposal_id: i32,
+    pub operator_id: i32,
+    pub approve: bool,
+    pub signature: Vec<u8>,
+}
+
+
+#[derive(Debug, Insertable)]
+#[diesel(table_name = schema::proposal_result, check_for_backend(Sqlite))]
+pub struct NewProposalResult {
+    pub proposal_id: i32,
+    pub data: Vec<u8>,
+}
+
+#[derive(Debug, Insertable)]
+#[diesel(table_name = schema::recovery_proposal_vote, check_for_backend(Sqlite))]
+pub struct NewRecoveryProposalVote {
+    pub proposal_id: i32,
+    pub recovery_operator_id: i32,
+    pub approve: bool,
+    pub signature: Vec<u8>,
+}
+
+#[derive(Debug, Insertable)]
+#[diesel(table_name = schema::recovery_wakeup_request, check_for_backend(Sqlite))]
+pub struct NewRecoveryWakeupRequest {
+    pub requested_by: i32,
+}

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

@@ -152,10 +152,101 @@ diesel::table! {
     }
 }
 
+diesel::table! {
+    operator (id) {
+        id -> Nullable<Integer>,
+        share -> Binary,
+        share_nonce -> Binary,
+        share_salt -> Binary,
+        created_at -> Integer,
+        updated_at -> Integer,
+    }
+}
+
+diesel::table! {
+    operator_identity (id) {
+        id -> Integer,
+        public_key -> Binary,
+        created_at -> Integer,
+        updated_at -> Integer,
+    }
+}
+
+diesel::table! {
+    proposal (id) {
+        id -> Integer,
+        kind -> Text,
+        payload -> Binary,
+        initiator_id -> Integer,
+        created_at -> Integer,
+        expires_at -> Integer,
+        status -> Text,
+    }
+}
+
+diesel::table! {
+    proposal_result (proposal_id) {
+        proposal_id -> Integer,
+        data -> Binary,
+        created_at -> Integer,
+    }
+}
+
+diesel::table! {
+    recovery_operator (id) {
+        id -> Integer,
+        share -> Binary,
+        share_nonce -> Binary,
+        share_salt -> Binary,
+        created_at -> Integer,
+        updated_at -> Integer,
+    }
+}
+
+diesel::table! {
+    recovery_operator_identity (id) {
+        id -> Integer,
+        public_key -> Binary,
+        created_at -> Integer,
+        updated_at -> Integer,
+    }
+}
+
+diesel::table! {
+    recovery_wakeup_request (id) {
+        id -> Integer,
+        requested_by -> Integer,
+        requested_at -> Integer,
+        cancelled_by -> Nullable<Integer>,
+        cancelled_at -> Nullable<Integer>,
+    }
+}
+
+diesel::table! {
+    recovery_proposal_vote (id) {
+        id -> Integer,
+        proposal_id -> Integer,
+        recovery_operator_id -> Integer,
+        approve -> Bool,
+        signature -> Binary,
+        voted_at -> Integer,
+    }
+}
+
+diesel::table! {
+    proposal_vote (id) {
+        id -> Integer,
+        proposal_id -> Integer,
+        operator_id -> Integer,
+        approve -> Bool,
+        signature -> Binary,
+        voted_at -> Integer,
+    }
+}
+
 diesel::table! {
     program_client (id) {
         id -> Integer,
-        nonce -> Integer,
         public_key -> Binary,
         metadata_id -> Integer,
         created_at -> Integer,
@@ -186,17 +277,6 @@ diesel::table! {
     }
 }
 
-diesel::table! {
-    useragent_client (id) {
-        id -> Integer,
-        nonce -> Integer,
-        public_key -> Binary,
-        key_type -> Integer,
-        created_at -> Integer,
-        updated_at -> Integer,
-    }
-}
-
 diesel::joinable!(aead_encrypted -> root_key_history (associated_root_key_id));
 diesel::joinable!(arbiter_settings -> root_key_history (root_key_id));
 diesel::joinable!(arbiter_settings -> tls_history (tls_id));
@@ -215,10 +295,24 @@ diesel::joinable!(evm_transaction_log -> evm_wallet_access (wallet_access_id));
 diesel::joinable!(evm_wallet -> aead_encrypted (aead_encrypted_id));
 diesel::joinable!(evm_wallet_access -> evm_wallet (wallet_id));
 diesel::joinable!(evm_wallet_access -> program_client (client_id));
+diesel::joinable!(operator -> operator_identity (id));
 diesel::joinable!(program_client -> client_metadata (metadata_id));
+diesel::joinable!(proposal -> operator_identity (initiator_id));
+diesel::joinable!(proposal_result -> proposal (proposal_id));
+diesel::joinable!(proposal_vote -> proposal (proposal_id));
+diesel::joinable!(proposal_vote -> operator_identity (operator_id));
+diesel::joinable!(recovery_operator -> recovery_operator_identity (id));
+diesel::joinable!(recovery_proposal_vote -> proposal (proposal_id));
+diesel::joinable!(recovery_proposal_vote -> recovery_operator_identity (recovery_operator_id));
+diesel::joinable!(recovery_wakeup_request -> operator_identity (requested_by));
 
 diesel::allow_tables_to_appear_in_same_query!(
     aead_encrypted,
+    proposal_result,
+    recovery_operator,
+    recovery_operator_identity,
+    recovery_wakeup_request,
+    recovery_proposal_vote,
     arbiter_settings,
     client_metadata,
     client_metadata_history,
@@ -233,8 +327,11 @@ diesel::allow_tables_to_appear_in_same_query!(
     evm_wallet,
     evm_wallet_access,
     integrity_envelope,
+    operator,
+    operator_identity,
     program_client,
+    proposal,
+    proposal_vote,
     root_key_history,
     tls_history,
-    useragent_client,
 );

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

@@ -1,17 +1,5 @@
-pub mod abi;
-pub mod safe_signer;
-
-use alloy::{
-    consensus::TxEip1559,
-    primitives::{TxKind, U256},
-};
-use chrono::Utc;
-use diesel::{ExpressionMethods as _, QueryDsl as _, QueryResult, insert_into, sqlite::Sqlite};
-use diesel_async::{AsyncConnection, RunQueryDsl};
-use kameo::actor::ActorRef;
-
 use crate::{
-    actors::keyholder::KeyHolder,
+    actors::vault::Vault,
     crypto::integrity,
     db::{
         self, DatabaseError,
@@ -27,6 +15,18 @@ use crate::{
     },
 };
 
+use alloy::{
+    consensus::TxEip1559,
+    primitives::{TxKind, U256},
+};
+use chrono::Utc;
+use diesel::{ExpressionMethods as _, QueryDsl as _, QueryResult, insert_into, sqlite::Sqlite};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use kameo::actor::ActorRef;
+
+pub mod abi;
+pub mod safe_signer;
+
 pub mod policies;
 mod utils;
 
@@ -41,7 +41,7 @@ pub enum PolicyError {
     NoMatchingGrant,
 
     #[error("Integrity error: {0}")]
-    Integrity(#[from] integrity::IntegrityError),
+    Integrity(#[from] integrity::Error),
 }
 
 #[derive(Debug, thiserror::Error)]
@@ -69,7 +69,7 @@ pub enum ListError {
     Database(#[from] DatabaseError),
 
     #[error("Integrity verification failed for grant")]
-    Integrity(#[from] integrity::IntegrityError),
+    Integrity(#[from] integrity::Error),
 }
 
 /// Controls whether a transaction should be executed or only validated
@@ -138,7 +138,7 @@ 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,
-    keyholder: ActorRef<KeyHolder>,
+    vault: ActorRef<Vault>,
 }
 
 impl Engine {
@@ -158,7 +158,7 @@ impl Engine {
             .map_err(DatabaseError::from)?
             .ok_or(PolicyError::NoMatchingGrant)?;
 
-        integrity::verify_entity(&mut conn, &self.keyholder, &grant.settings, grant.id).await?;
+        integrity::verify_entity(&mut conn, &self.vault, &grant.settings, grant.id).await?;
 
         let mut violations = check_shared_constraints(
             &context,
@@ -179,24 +179,22 @@ impl Engine {
         }
 
         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,
-                            wallet_access_id: context.target.id,
-                            chain_id: context.chain.into(),
-                            eth_value: utils::u256_to_bytes(context.value).to_vec(),
-                            signed_at: Utc::now().into(),
-                        })
-                        .returning(evm_transaction_log::id)
-                        .get_result(conn)
-                        .await?;
+            conn.transaction(async |conn| {
+                let log_id: i32 = insert_into(evm_transaction_log::table)
+                    .values(&NewEvmTransactionLog {
+                        grant_id: grant.common_settings_id,
+                        wallet_access_id: context.target.id,
+                        chain_id: context.chain.into(),
+                        eth_value: utils::u256_to_bytes(context.value).to_vec(),
+                        signed_at: Utc::now().into(),
+                    })
+                    .returning(evm_transaction_log::id)
+                    .get_result(&mut *conn)
+                    .await?;
 
-                    P::record_transaction(&context, meaning, log_id, &grant, conn).await?;
+                P::record_transaction(&context, meaning, log_id, &grant, &mut *conn).await?;
 
-                    QueryResult::Ok(())
-                })
+                QueryResult::Ok(())
             })
             .await
             .map_err(DatabaseError::from)?;
@@ -207,8 +205,8 @@ impl Engine {
 }
 
 impl Engine {
-    pub const fn new(db: db::DatabasePool, keyholder: ActorRef<KeyHolder>) -> Self {
-        Self { db, keyholder }
+    pub const fn new(db: db::DatabasePool, vault: ActorRef<Vault>) -> Self {
+        Self { db, vault }
     }
 
     pub async fn create_grant<P: Policy>(
@@ -219,57 +217,55 @@ impl Engine {
         P::Settings: Clone,
     {
         let mut conn = self.db.get().await?;
-        let keyholder = self.keyholder.clone();
+        let vault = self.vault.clone();
 
         let id = conn
-            .transaction(|conn| {
-                Box::pin(async move {
-                    use schema::evm_basic_grant;
+            .transaction(async |conn| {
+                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(),
-                            wallet_access_id: full_grant.shared.wallet_access_id,
-                            valid_from: full_grant.shared.valid_from.map(SqliteTimestamp),
-                            valid_until: full_grant.shared.valid_until.map(SqliteTimestamp),
-                            max_gas_fee_per_gas: full_grant
-                                .shared
-                                .max_gas_fee_per_gas
-                                .map(|fee| utils::u256_to_bytes(fee).to_vec()),
-                            max_priority_fee_per_gas: full_grant
-                                .shared
-                                .max_priority_fee_per_gas
-                                .map(|fee| utils::u256_to_bytes(fee).to_vec()),
-                            rate_limit_count: full_grant
-                                .shared
-                                .rate_limit
-                                .as_ref()
-                                .map(|rl| rl.count as i32),
-                            rate_limit_window_secs: full_grant
-                                .shared
-                                .rate_limit
-                                .as_ref()
-                                .map(|rl| rl.window.num_seconds() as i32),
-                            revoked_at: None,
-                        })
-                        .returning(evm_basic_grant::all_columns)
-                        .get_result(conn)
-                        .await?;
+                #[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(),
+                        wallet_access_id: full_grant.shared.wallet_access_id,
+                        valid_from: full_grant.shared.valid_from.map(SqliteTimestamp),
+                        valid_until: full_grant.shared.valid_until.map(SqliteTimestamp),
+                        max_gas_fee_per_gas: full_grant
+                            .shared
+                            .max_gas_fee_per_gas
+                            .map(|fee| utils::u256_to_bytes(fee).to_vec()),
+                        max_priority_fee_per_gas: full_grant
+                            .shared
+                            .max_priority_fee_per_gas
+                            .map(|fee| utils::u256_to_bytes(fee).to_vec()),
+                        rate_limit_count: full_grant
+                            .shared
+                            .rate_limit
+                            .as_ref()
+                            .map(|rl| rl.count as i32),
+                        rate_limit_window_secs: full_grant
+                            .shared
+                            .rate_limit
+                            .as_ref()
+                            .map(|rl| rl.window.num_seconds() as i32),
+                        revoked_at: None,
+                    })
+                    .returning(evm_basic_grant::all_columns)
+                    .get_result(&mut *conn)
+                    .await?;
 
-                    P::create_grant(&basic_grant, &full_grant.specific, conn).await?;
+                P::create_grant(&basic_grant, &full_grant.specific, &mut *conn).await?;
 
-                    integrity::sign_entity(conn, &keyholder, &full_grant, basic_grant.id)
-                        .await
-                        .map_err(|_| diesel::result::Error::RollbackTransaction)?;
+                integrity::sign_entity(&mut *conn, &vault, &full_grant, basic_grant.id)
+                    .await
+                    .map_err(|_| diesel::result::Error::RollbackTransaction)?;
 
-                    QueryResult::Ok(basic_grant.id)
-                })
+                QueryResult::Ok(basic_grant.id)
             })
             .await?;
 
@@ -289,7 +285,7 @@ impl Engine {
 
         // Verify integrity of all grants before returning any results
         for grant in &all_grants {
-            integrity::verify_entity(conn, &self.keyholder, &grant.settings, grant.id).await?;
+            integrity::verify_entity(conn, &self.vault, &grant.settings, grant.id).await?;
         }
 
         Ok(all_grants.into_iter().map(|g| Grant {
@@ -363,7 +359,8 @@ mod tests {
     use crate::db::{
         self, DatabaseConnection,
         models::{
-            EvmBasicGrant, EvmWalletAccess, NewEvmBasicGrant, NewEvmTransactionLog, SqliteTimestamp,
+            EvmBasicGrant, EvmWalletAccess, EvmWalletId, NewEvmBasicGrant, NewEvmTransactionLog,
+            SqliteTimestamp,
         },
         schema::{evm_basic_grant, evm_transaction_log},
     };
@@ -381,7 +378,7 @@ mod tests {
         EvalContext {
             target: EvmWalletAccess {
                 id: WALLET_ACCESS_ID,
-                wallet_id: 10,
+                wallet_id: EvmWalletId::from_raw(5),
                 client_id: 20,
                 created_at: SqliteTimestamp(Utc::now()),
             },

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

@@ -1,4 +1,8 @@
-use std::fmt::Display;
+use crate::{
+    crypto::integrity::v1::Integrable,
+    db::models::{EvmBasicGrant, EvmWalletAccess},
+    evm::utils,
+};
 
 use alloy::primitives::{Address, Bytes, ChainId, U256};
 use chrono::{DateTime, Duration, Utc};
@@ -6,15 +10,9 @@ use diesel::{
     ExpressionMethods as _, QueryDsl, SelectableHelper, result::QueryResult, sqlite::Sqlite,
 };
 use diesel_async::{AsyncConnection, RunQueryDsl};
-
+use std::fmt::Display;
 use thiserror::Error;
 
-use crate::{
-    crypto::integrity::v1::Integrable,
-    db::models::{EvmBasicGrant, EvmWalletAccess},
-    evm::utils,
-};
-
 pub mod ether_transfer;
 pub mod token_transfers;
 

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

@@ -1,30 +1,32 @@
-use std::collections::HashMap;
-use std::fmt::Display;
-
-use alloy::primitives::{Address, U256};
-use chrono::{DateTime, Duration, Utc};
-use diesel::dsl::{auto_type, insert_into};
-use diesel::prelude::*;
-use diesel::sqlite::Sqlite;
-use diesel_async::{AsyncConnection, RunQueryDsl};
-
-use crate::crypto::integrity::v1::Integrable;
-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::{
-    CombinedSettings, Grant, SharedGrantSettings, SpecificGrant, SpecificMeaning, VolumeRateLimit,
-};
+use super::{DatabaseID, EvalContext, EvalViolation};
 use crate::{
+    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::{
+    dsl::{auto_type, insert_into},
+    prelude::*,
+    sqlite::Sqlite,
+};
+use diesel_async::{AsyncConnection, RunQueryDsl};
+use std::{collections::HashMap, fmt::Display};
+
 #[auto_type]
 fn grant_join() -> _ {
     evm_ether_transfer_grant::table.inner_join(
@@ -32,8 +34,6 @@ fn grant_join() -> _ {
     )
 }
 
-use super::{DatabaseID, EvalContext, EvalViolation};
-
 // Plain ether transfer
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub struct Meaning {

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

@@ -1,25 +1,27 @@
+use super::{EtherTransfer, Settings};
+use crate::{
+    db::{
+        self, DatabaseConnection,
+        models::{
+            EvmBasicGrant, EvmWalletAccess, EvmWalletId, 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::{
-        CombinedSettings, EvalContext, EvalViolation, Grant, Policy, SharedGrantSettings,
-        VolumeRateLimit,
-    },
-    utils,
-};
-
-use super::{EtherTransfer, Settings};
-
 const WALLET_ACCESS_ID: i32 = 1;
 const CHAIN_ID: alloy::primitives::ChainId = 1;
 
@@ -30,7 +32,7 @@ fn ctx(to: Address, value: U256) -> EvalContext {
     EvalContext {
         target: EvmWalletAccess {
             id: WALLET_ACCESS_ID,
-            wallet_id: 10,
+            wallet_id: EvmWalletId::from_raw(10),
             client_id: 20,
             created_at: SqliteTimestamp(Utc::now()),
         },

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

@@ -1,16 +1,4 @@
-use std::collections::HashMap;
-
-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};
 use crate::{
     crypto::integrity::Integrable,
     db::models::{
@@ -18,20 +6,33 @@ use crate::{
         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::dsl::{auto_type, insert_into};
-use diesel::prelude::*;
-use diesel::sqlite::Sqlite;
+use diesel::{
+    dsl::{auto_type, insert_into},
+    prelude::*,
+    sqlite::Sqlite,
+};
 use diesel_async::{AsyncConnection, RunQueryDsl};
-
-use super::{DatabaseID, EvalContext, EvalViolation};
+use std::collections::HashMap;
 
 #[auto_type]
 fn grant_join() -> _ {

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

@@ -1,25 +1,28 @@
-use alloy::primitives::{Address, Bytes, U256, address};
-use alloy::sol_types::SolCall;
+use super::{Settings, TokenTransfer};
+use crate::{
+    db::{
+        self, DatabaseConnection,
+        models::{EvmBasicGrant, EvmWalletAccess, EvmWalletId, 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::{
-        CombinedSettings, 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");
@@ -42,7 +45,7 @@ fn ctx(to: Address, calldata: Bytes) -> EvalContext {
     EvalContext {
         target: EvmWalletAccess {
             id: WALLET_ACCESS_ID,
-            wallet_id: 10,
+            wallet_id: EvmWalletId::from_raw(10),
             client_id: 20,
             created_at: SqliteTimestamp(Utc::now()),
         },

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

@@ -1,4 +1,4 @@
-use std::sync::Mutex;
+use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
 
 use alloy::{
     consensus::SignableTransaction,
@@ -6,9 +6,9 @@ use alloy::{
     primitives::{Address, B256, ChainId, Signature},
     signers::{Error, Result, Signer, SignerSync, utils::secret_key_to_address},
 };
-use arbiter_crypto::safecell::{SafeCell, SafeCellHandle as _};
 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.
@@ -44,7 +44,7 @@ impl std::fmt::Debug for SafeSigner {
 /// Returns the protected key bytes and the derived Ethereum address.
 pub fn generate(rng: &mut impl rand::Rng) -> (SafeCell<[u8; 32]>, Address) {
     loop {
-        let mut cell = SafeCell::new_inline(|w: &mut [u8; 32]| {
+        let mut cell = SafeCell::new_inline_default(|w: &mut [u8; 32]| {
             rng.fill_bytes(w);
         });
 

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 struct LengthError {
-    pub expected: usize,
-    pub actual: usize,
+pub(super) struct LengthError {
+    pub(super) expected: usize,
+    pub(super) actual: usize,
 }
 
 pub const fn u256_to_bytes(value: U256) -> [u8; 32] {
     value.to_le_bytes()
 }
-pub fn bytes_to_u256(bytes: &[u8]) -> Option<U256> {
+pub(super) fn bytes_to_u256(bytes: &[u8]) -> Option<U256> {
     let bytes: [u8; 32] = bytes.try_into().ok()?;
     Some(U256::from_le_bytes(bytes))
 }
 
-pub fn try_bytes_to_u256(bytes: &[u8]) -> diesel::result::QueryResult<U256> {
+pub(super) 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

@@ -1,3 +1,7 @@
+use crate::{
+    grpc::request_tracker::RequestTracker,
+    peers::client::{ClientConnection, session::ClientSession},
+};
 use arbiter_proto::{
     proto::client::{
         ClientRequest, ClientResponse, client_request::Payload as ClientRequestPayload,
@@ -5,15 +9,11 @@ use arbiter_proto::{
     },
     transport::{Receiver, Sender, grpc::GrpcBi},
 };
+
 use kameo::actor::{ActorRef, Spawn as _};
 use tonic::Status;
 use tracing::{info, warn};
 
-use crate::{
-    actors::client::{ClientConnection, session::ClientSession},
-    grpc::request_tracker::RequestTracker,
-};
-
 mod auth;
 mod evm;
 mod inbound;

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

@@ -1,3 +1,7 @@
+use crate::{
+    grpc::{Convert, request_tracker::RequestTracker},
+    peers::client::{ClientConnection, auth},
+};
 use arbiter_crypto::authn;
 use arbiter_proto::{
     ClientMetadata,
@@ -5,7 +9,8 @@ use arbiter_proto::{
         client::{
             ClientRequest, ClientResponse,
             auth::{
-                self as proto_auth, AuthChallengeRequest as ProtoAuthChallengeRequest,
+                self as proto_auth, AuthChallenge as ProtoAuthChallenge,
+                AuthChallengeRequest as ProtoAuthChallengeRequest,
                 AuthChallengeSolution as ProtoAuthChallengeSolution, AuthResult as ProtoAuthResult,
                 request::Payload as AuthRequestPayload, response::Payload as AuthResponsePayload,
             },
@@ -16,22 +21,18 @@ use arbiter_proto::{
     },
     transport::{Bi, Error as TransportError, Receiver, Sender, grpc::GrpcBi},
 };
+
 use async_trait::async_trait;
 use tonic::Status;
 use tracing::warn;
 
-use crate::{
-    actors::client::{ClientConnection, auth},
-    grpc::request_tracker::RequestTracker,
-};
-
-pub struct AuthTransportAdapter<'a> {
+pub(super) struct AuthTransportAdapter<'a> {
     bi: &'a mut GrpcBi<ClientRequest, ClientResponse>,
     request_tracker: &'a mut RequestTracker,
 }
 
 impl<'a> AuthTransportAdapter<'a> {
-    pub const fn new(
+    pub(super) const fn new(
         bi: &'a mut GrpcBi<ClientRequest, ClientResponse>,
         request_tracker: &'a mut RequestTracker,
     ) -> Self {
@@ -62,14 +63,14 @@ impl<'a> AuthTransportAdapter<'a> {
 }
 
 #[async_trait]
-impl Sender<Result<auth::Outbound, auth::ClientAuthError>> for AuthTransportAdapter<'_> {
+impl Sender<Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {
     async fn send(
         &mut self,
-        item: Result<auth::Outbound, auth::ClientAuthError>,
+        item: Result<auth::Outbound, auth::Error>,
     ) -> Result<(), TransportError> {
         let payload = match item {
-            Ok(message) => message.into(),
-            Err(err) => AuthResponsePayload::Result(ProtoAuthResult::from(err).into()),
+            Ok(message) => message.convert(),
+            Err(err) => err.convert(),
         };
 
         self.send_client_response(payload).await
@@ -132,7 +133,7 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
                 };
                 Some(auth::Inbound::AuthChallengeRequest {
                     pubkey,
-                    metadata: client_metadata_from_proto(client_info),
+                    metadata: client_info.convert(),
                 })
             }
             AuthRequestPayload::ChallengeSolution(ProtoAuthChallengeSolution { signature }) => {
@@ -148,21 +149,71 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
     }
 }
 
-impl Bi<auth::Inbound, Result<auth::Outbound, auth::ClientAuthError>> for AuthTransportAdapter<'_> {}
+impl Bi<auth::Inbound, Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {}
 
-fn client_metadata_from_proto(metadata: ProtoClientInfo) -> ClientMetadata {
-    ClientMetadata {
-        name: metadata.name,
-        description: metadata.description,
-        version: metadata.version,
+impl Convert for ProtoClientInfo {
+    type Output = ClientMetadata;
+
+    fn convert(self) -> Self::Output {
+        ClientMetadata {
+            name: self.name,
+            description: self.description,
+            version: self.version,
+        }
     }
 }
 
-pub async fn start(
+impl Convert for auth::Error {
+    type Output = AuthResponsePayload;
+
+    fn convert(self) -> Self::Output {
+        use auth::Error::{
+            ApproveError, DatabaseOperationFailed, DatabasePoolUnavailable, IntegrityCheckFailed,
+            InvalidChallengeSolution, Transport,
+        };
+        AuthResponsePayload::Result(
+            match self {
+                InvalidChallengeSolution => ProtoAuthResult::InvalidSignature,
+                ApproveError(auth::ApproveError::Denied) => ProtoAuthResult::ApprovalDenied,
+                ApproveError(auth::ApproveError::Upstream(
+                    crate::actors::flow_coordinator::ApprovalError::NoOperatorsConnected,
+                )) => ProtoAuthResult::NoOperatorsOnline,
+                ApproveError(auth::ApproveError::Internal)
+                | DatabasePoolUnavailable
+                | DatabaseOperationFailed
+                | IntegrityCheckFailed
+                | Transport => ProtoAuthResult::Internal,
+            }
+            .into(),
+        )
+    }
+}
+
+impl Convert for auth::Outbound {
+    type Output = AuthResponsePayload;
+
+    fn convert(self) -> Self::Output {
+        match self {
+            Self::AuthChallenge { challenge } => {
+                AuthResponsePayload::Challenge(ProtoAuthChallenge {
+                    timestamp_nanos: challenge
+                        .timestamp
+                        .timestamp_nanos_opt()
+                        .expect("timestamp within range")
+                        as u64,
+                    random: challenge.nonce.to_vec(),
+                })
+            }
+            Self::AuthSuccess => AuthResponsePayload::Result(ProtoAuthResult::Success.into()),
+        }
+    }
+}
+
+pub(super) async fn start(
     conn: &mut ClientConnection,
     bi: &mut GrpcBi<ClientRequest, ClientResponse>,
     request_tracker: &mut RequestTracker,
-) -> Result<i32, auth::ClientAuthError> {
+) -> Result<i32, auth::Error> {
     let mut transport = AuthTransportAdapter::new(bi, request_tracker);
     auth::authenticate(conn, &mut transport).await
 }

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

@@ -1,3 +1,10 @@
+use crate::{
+    grpc::{
+        Convert, TryConvert,
+        common::inbound::{RawEvmAddress, RawEvmTransaction},
+    },
+    peers::client::session::{ClientSession, HandleSignTransaction, SignTransactionRpcError},
+};
 use arbiter_proto::proto::{
     client::{
         client_response::Payload as ClientResponsePayload,
@@ -11,18 +18,11 @@ use arbiter_proto::proto::{
         evm_sign_transaction_response::Result as EvmSignTransactionResult,
     },
 };
+
 use kameo::actor::ActorRef;
 use tonic::Status;
 use tracing::warn;
 
-use crate::{
-    actors::client::session::{ClientSession, HandleSignTransaction, SignTransactionRpcError},
-    grpc::{
-        Convert, TryConvert,
-        common::inbound::{RawEvmAddress, RawEvmTransaction},
-    },
-};
-
 const fn wrap_response(payload: EvmResponsePayload) -> ClientResponsePayload {
     ClientResponsePayload::Evm(proto_evm::Response {
         payload: Some(payload),

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

@@ -1,3 +1,7 @@
+use crate::{
+    actors::vault::VaultState,
+    peers::client::session::{ClientSession, Error, HandleQueryVaultState},
+};
 use arbiter_proto::proto::{
     client::{
         client_response::Payload as ClientResponsePayload,
@@ -8,15 +12,11 @@ use arbiter_proto::proto::{
     },
     shared::VaultState as ProtoVaultState,
 };
+
 use kameo::{actor::ActorRef, error::SendError};
 use tonic::Status;
 use tracing::warn;
 
-use crate::actors::{
-    client::session::{ClientSession, ClientSessionError, HandleQueryVaultState},
-    keyholder::KeyHolderState,
-};
-
 pub(super) async fn dispatch(
     actor: &ActorRef<ClientSession>,
     req: proto_vault::Request,
@@ -30,12 +30,10 @@ pub(super) async fn dispatch(
     match payload {
         VaultRequestPayload::QueryState(()) => {
             let state = match actor.ask(HandleQueryVaultState {}).await {
-                Ok(KeyHolderState::Unbootstrapped) => ProtoVaultState::Unbootstrapped,
-                Ok(KeyHolderState::Sealed) => ProtoVaultState::Sealed,
-                Ok(KeyHolderState::Unsealed) => ProtoVaultState::Unsealed,
-                Err(SendError::HandlerError(ClientSessionError::Internal)) => {
-                    ProtoVaultState::Error
-                }
+                Ok(VaultState::Unbootstrapped) => ProtoVaultState::Unbootstrapped,
+                Ok(VaultState::Sealed) => ProtoVaultState::Sealed,
+                Ok(VaultState::Unsealed) => ProtoVaultState::Unsealed,
+                Err(SendError::HandlerError(Error::Internal)) => ProtoVaultState::Error,
                 Err(err) => {
                     warn!(error = ?err, "Failed to query vault state");
                     ProtoVaultState::Error

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

@@ -1,2 +1,2 @@
-pub mod inbound;
-pub mod outbound;
+pub(super) mod inbound;
+pub(super) mod outbound;

server/crates/arbiter-server/src/grpc/common/inbound.rs

@@ -1,8 +1,8 @@
-use alloy::{consensus::TxEip1559, primitives::Address, rlp::Decodable as _};
-
 use crate::grpc::TryConvert;
 
-pub struct RawEvmAddress(pub Vec<u8>);
+use alloy::{consensus::TxEip1559, primitives::Address, rlp::Decodable as _};
+
+pub(in crate::grpc) struct RawEvmAddress(pub(in crate::grpc) Vec<u8>);
 impl TryConvert for RawEvmAddress {
     type Output = Address;
 
@@ -21,7 +21,7 @@ impl TryConvert for RawEvmAddress {
     }
 }
 
-pub struct RawEvmTransaction(pub Vec<u8>);
+pub(in crate::grpc) struct RawEvmTransaction(pub(in crate::grpc) Vec<u8>);
 impl TryConvert for RawEvmTransaction {
     type Output = TxEip1559;
 

server/crates/arbiter-server/src/grpc/common/outbound.rs

@@ -1,4 +1,10 @@
-use alloy::primitives::U256;
+use crate::{
+    evm::{
+        PolicyError, VetError,
+        policies::{EvalViolation, SpecificMeaning},
+    },
+    grpc::Convert,
+};
 use arbiter_proto::proto::{
     evm::{
         EvmError as ProtoEvmError,
@@ -14,13 +20,7 @@ use arbiter_proto::proto::{
     },
 };
 
-use crate::{
-    evm::{
-        PolicyError, VetError,
-        policies::{EvalViolation, SpecificMeaning},
-    },
-    grpc::Convert,
-};
+use alloy::primitives::U256;
 
 fn u256_to_proto_bytes(value: U256) -> Vec<u8> {
     value.to_be_bytes::<32>().to_vec()

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

@@ -1,23 +1,20 @@
+use crate::peers::{client::ClientConnection, operator::OperatorConnection};
 use arbiter_proto::{
     proto::{
         client::{ClientRequest, ClientResponse},
-        user_agent::{UserAgentRequest, UserAgentResponse},
+        operator::{OperatorRequest, OperatorResponse},
     },
     transport::grpc::GrpcBi,
 };
+
 use tokio_stream::wrappers::ReceiverStream;
 use tonic::{Request, Response, Status, async_trait};
 use tracing::info;
 
-use crate::{
-    actors::{client::ClientConnection, user_agent::UserAgentConnection},
-    grpc::user_agent::start,
-};
-
 mod request_tracker;
 
 pub mod client;
-pub mod user_agent;
+pub mod operator;
 
 mod common;
 
@@ -36,7 +33,7 @@ pub trait TryConvert {
 
 #[async_trait]
 impl arbiter_proto::proto::arbiter_service_server::ArbiterService for super::Server {
-    type UserAgentStream = ReceiverStream<Result<UserAgentResponse, Status>>;
+    type OperatorStream = ReceiverStream<Result<OperatorResponse, Status>>;
     type ClientStream = ReceiverStream<Result<ClientResponse, Status>>;
 
     #[tracing::instrument(level = "debug", skip(self))]
@@ -55,23 +52,23 @@ impl arbiter_proto::proto::arbiter_service_server::ArbiterService for super::Ser
     }
 
     #[tracing::instrument(level = "debug", skip(self))]
-    async fn user_agent(
+    async fn operator(
         &self,
-        request: Request<tonic::Streaming<UserAgentRequest>>,
-    ) -> Result<Response<Self::UserAgentStream>, Status> {
+        request: Request<tonic::Streaming<OperatorRequest>>,
+    ) -> Result<Response<Self::OperatorStream>, Status> {
         let req_stream = request.into_inner();
 
         let (bi, rx) = GrpcBi::from_bi_stream(req_stream);
 
-        tokio::spawn(start(
-            UserAgentConnection {
+        tokio::spawn(operator::start(
+            OperatorConnection {
                 db: self.context.db.clone(),
                 actors: self.context.actors.clone(),
             },
             bi,
         ));
 
-        info!(event = "connection established", "grpc.user_agent");
+        info!(event = "connection established", "grpc.operator");
 
         Ok(Response::new(rx))
     }

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

@@ -1,29 +1,30 @@
-use tokio::sync::mpsc;
-
+use crate::{
+    grpc::request_tracker::RequestTracker,
+    peers::operator::{OutOfBand, OperatorConnection, OperatorSession},
+};
 use arbiter_proto::{
-    proto::user_agent::{
-        UserAgentRequest, UserAgentResponse,
-        user_agent_request::Payload as UserAgentRequestPayload,
-        user_agent_response::Payload as UserAgentResponsePayload,
+    proto::operator::{
+        OperatorRequest, OperatorResponse,
+        operator_request::Payload as OperatorRequestPayload,
+        operator_response::Payload as OperatorResponsePayload,
     },
     transport::{Error as TransportError, Receiver, Sender, grpc::GrpcBi},
 };
+
 use async_trait::async_trait;
-use kameo::actor::{ActorRef, Spawn as _};
+use kameo::actor::ActorRef;
+use tokio::sync::mpsc;
 use tonic::Status;
 use tracing::{error, info, warn};
 
-use crate::{
-    actors::user_agent::{OutOfBand, UserAgentConnection, UserAgentSession},
-    grpc::request_tracker::RequestTracker,
-};
-
 mod auth;
 mod evm;
+mod governance;
 mod inbound;
 mod outbound;
 mod sdk_client;
 mod vault;
+mod vault_gate;
 
 pub struct OutOfBandAdapter(mpsc::Sender<OutOfBand>);
 
@@ -38,8 +39,8 @@ impl Sender<OutOfBand> for OutOfBandAdapter {
 }
 
 async fn dispatch_loop(
-    mut bi: GrpcBi<UserAgentRequest, UserAgentResponse>,
-    actor: ActorRef<UserAgentSession>,
+    mut bi: GrpcBi<OperatorRequest, OperatorResponse>,
+    actor: ActorRef<OperatorSession>,
     mut receiver: mpsc::Receiver<OutOfBand>,
     mut request_tracker: RequestTracker,
 ) {
@@ -53,7 +54,7 @@ async fn dispatch_loop(
 
                 let payload = sdk_client::out_of_band_payload(oob);
 
-                if bi.send(Ok(UserAgentResponse { id: None, payload: Some(payload) })).await.is_err() {
+                if bi.send(Ok(OperatorResponse { id: None, payload: Some(payload) })).await.is_err() {
                     return;
                 }
             }
@@ -64,7 +65,7 @@ async fn dispatch_loop(
                 let conn = match message {
                     Ok(conn) => conn,
                     Err(err) => {
-                        warn!(error = ?err, "Failed to receive user agent request");
+                        warn!(error = ?err, "Failed to receive operator request");
                         return;
                     }
                 };
@@ -78,13 +79,13 @@ async fn dispatch_loop(
                 };
 
                 let Some(payload) = conn.payload else {
-                    let _ = bi.send(Err(Status::invalid_argument("Missing user-agent request payload"))).await;
+                    let _ = bi.send(Err(Status::invalid_argument("Missing operator request payload"))).await;
                     return;
                 };
 
                 match dispatch_inner(&actor, payload).await {
                     Ok(Some(response)) => {
-                        if bi.send(Ok(UserAgentResponse {
+                        if bi.send(Ok(OperatorResponse {
                             id: Some(request_id),
                             payload: Some(response),
                         })).await.is_err() {
@@ -93,7 +94,7 @@ async fn dispatch_loop(
                     }
                     Ok(None) => {}
                     Err(status) => {
-                        error!(?status, "Failed to process user agent request");
+                        error!(?status, "Failed to process operator request");
                         let _ = bi.send(Err(status)).await;
                         return;
                     }
@@ -104,41 +105,43 @@ async fn dispatch_loop(
 }
 
 async fn dispatch_inner(
-    actor: &ActorRef<UserAgentSession>,
-    payload: UserAgentRequestPayload,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+    actor: &ActorRef<OperatorSession>,
+    payload: OperatorRequestPayload,
+) -> Result<Option<OperatorResponsePayload>, Status> {
     match payload {
-        UserAgentRequestPayload::Vault(req) => vault::dispatch(actor, req).await,
-        UserAgentRequestPayload::Evm(req) => evm::dispatch(actor, req).await,
-        UserAgentRequestPayload::SdkClient(req) => sdk_client::dispatch(actor, req).await,
-        UserAgentRequestPayload::Auth(..) => {
-            warn!("Unsupported post-auth user agent auth request");
-            Err(Status::invalid_argument("Unsupported user-agent request"))
+        OperatorRequestPayload::Vault(req) => vault::dispatch(actor, req).await,
+        OperatorRequestPayload::Evm(req) => evm::dispatch(actor, req).await,
+        OperatorRequestPayload::SdkClient(req) => sdk_client::dispatch(actor, req).await,
+        OperatorRequestPayload::Auth(..) => {
+            warn!("Unsupported post-auth operator auth request");
+            Err(Status::invalid_argument("Unsupported operator request"))
         }
+        OperatorRequestPayload::Governance(req) => governance::dispatch(actor, req).await,
     }
 }
 
 pub async fn start(
-    mut conn: UserAgentConnection,
-    mut bi: GrpcBi<UserAgentRequest, UserAgentResponse>,
+    mut conn: OperatorConnection,
+    mut bi: GrpcBi<OperatorRequest, OperatorResponse>,
 ) {
     let mut request_tracker = RequestTracker::default();
 
-    let pubkey = match auth::start(&mut conn, &mut bi, &mut request_tracker).await {
-        Ok(pubkey) => pubkey,
-        Err(e) => {
-            warn!(error = ?e, "Authentication failed");
-            return;
-        }
-    };
-
     let (oob_sender, oob_receiver) = mpsc::channel(16);
     let oob_adapter = OutOfBandAdapter(oob_sender);
 
-    let actor = UserAgentSession::spawn(UserAgentSession::new(conn, Box::new(oob_adapter)));
-    let actor_for_cleanup = actor.clone();
+    let actor = {
+        let transport = auth::AuthTransportAdapter::new(&mut bi, &mut request_tracker);
+        match crate::peers::operator::start(&mut conn, transport, Box::new(oob_adapter)).await {
+            Ok(actor) => actor,
+            Err(e) => {
+                warn!(error = ?e, "Operator connection failed");
+                return;
+            }
+        }
+    };
 
-    info!(?pubkey, "User authenticated successfully");
-    dispatch_loop(bi, actor, oob_receiver, request_tracker).await;
-    actor_for_cleanup.kill();
+    info!("Operator session established");
+
+    dispatch_loop(bi, actor.clone(), oob_receiver, request_tracker).await;
+    actor.kill();
 }

server/crates/arbiter-server/src/grpc/operator/auth.rs

@@ -1,35 +1,32 @@
+use crate::{grpc::request_tracker::RequestTracker, peers::operator::auth};
 use arbiter_crypto::authn;
 use arbiter_proto::{
-    proto::user_agent::{
-        UserAgentRequest, UserAgentResponse,
+    proto::operator::{
+        OperatorRequest, OperatorResponse,
         auth::{
             self as proto_auth, AuthChallenge as ProtoAuthChallenge,
             AuthChallengeRequest as ProtoAuthChallengeRequest,
             AuthChallengeSolution as ProtoAuthChallengeSolution, AuthResult as ProtoAuthResult,
             request::Payload as AuthRequestPayload, response::Payload as AuthResponsePayload,
         },
-        user_agent_request::Payload as UserAgentRequestPayload,
-        user_agent_response::Payload as UserAgentResponsePayload,
+        operator_request::Payload as OperatorRequestPayload,
+        operator_response::Payload as OperatorResponsePayload,
     },
     transport::{Bi, Error as TransportError, Receiver, Sender, grpc::GrpcBi},
 };
+
 use async_trait::async_trait;
 use tonic::Status;
 use tracing::warn;
 
-use crate::{
-    actors::user_agent::{UserAgentConnection, auth},
-    grpc::request_tracker::RequestTracker,
-};
-
-pub struct AuthTransportAdapter<'a> {
-    bi: &'a mut GrpcBi<UserAgentRequest, UserAgentResponse>,
-    request_tracker: &'a mut RequestTracker,
+pub(super) struct AuthTransportAdapter<'a> {
+    pub(super) bi: &'a mut GrpcBi<OperatorRequest, OperatorResponse>,
+    pub(super) request_tracker: &'a mut RequestTracker,
 }
 
 impl<'a> AuthTransportAdapter<'a> {
-    pub const fn new(
-        bi: &'a mut GrpcBi<UserAgentRequest, UserAgentResponse>,
+    pub(super) const fn new(
+        bi: &'a mut GrpcBi<OperatorRequest, OperatorResponse>,
         request_tracker: &'a mut RequestTracker,
     ) -> Self {
         Self {
@@ -38,18 +35,34 @@ impl<'a> AuthTransportAdapter<'a> {
         }
     }
 
-    async fn send_user_agent_response(
+    pub(super) const fn bi_mut(&mut self) -> &mut GrpcBi<OperatorRequest, OperatorResponse> {
+        self.bi
+    }
+
+    pub(super) const fn tracker_mut(&mut self) -> &mut RequestTracker {
+        self.request_tracker
+    }
+
+    pub(super) async fn send_response_payload(
+        &mut self,
+        payload: OperatorResponsePayload,
+    ) -> Result<(), TransportError> {
+        self.bi
+            .send(Ok(OperatorResponse {
+                id: Some(self.request_tracker.current_request_id()),
+                payload: Some(payload),
+            }))
+            .await
+    }
+
+    async fn send_operator_response(
         &mut self,
         payload: AuthResponsePayload,
     ) -> Result<(), TransportError> {
-        self.bi
-            .send(Ok(UserAgentResponse {
-                id: Some(self.request_tracker.current_request_id()),
-                payload: Some(UserAgentResponsePayload::Auth(proto_auth::Response {
-                    payload: Some(payload),
-                })),
-            }))
-            .await
+        self.send_response_payload(OperatorResponsePayload::Auth(proto_auth::Response {
+            payload: Some(payload),
+        }))
+        .await
     }
 }
 
@@ -61,8 +74,15 @@ impl Sender<Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {
     ) -> Result<(), TransportError> {
         use auth::{Error, Outbound};
         let payload = match item {
-            Ok(Outbound::AuthChallenge { nonce }) => {
-                AuthResponsePayload::Challenge(ProtoAuthChallenge { nonce })
+            Ok(Outbound::AuthChallenge { challenge }) => {
+                AuthResponsePayload::Challenge(ProtoAuthChallenge {
+                    timestamp_nanos: challenge
+                        .timestamp
+                        .timestamp_nanos_opt()
+                        .expect("timestamp within range")
+                        as u64,
+                    random: challenge.nonce.to_vec(),
+                })
             }
             Ok(Outbound::AuthSuccess) => {
                 AuthResponsePayload::Result(ProtoAuthResult::Success.into())
@@ -87,7 +107,7 @@ impl Sender<Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {
             }
         };
 
-        self.send_user_agent_response(payload).await
+        self.send_operator_response(payload).await
     }
 }
 
@@ -97,7 +117,7 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
         let request = match self.bi.recv().await? {
             Ok(request) => request,
             Err(error) => {
-                warn!(error = ?error, "Failed to receive user agent auth request");
+                warn!(error = ?error, "Failed to receive operator auth request");
                 return None;
             }
         };
@@ -113,16 +133,16 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
         let Some(payload) = request.payload else {
             warn!(
                 event = "received request with empty payload",
-                "grpc.useragent.auth_adapter"
+                "grpc.operator.auth_adapter"
             );
             return None;
         };
 
-        let UserAgentRequestPayload::Auth(auth_request) = payload else {
+        let OperatorRequestPayload::Auth(auth_request) = payload else {
             let _ = self
                 .bi
                 .send(Err(Status::invalid_argument(
-                    "Unsupported user-agent auth request",
+                    "Unsupported operator auth request",
                 )))
                 .await;
             return None;
@@ -131,7 +151,7 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
         let Some(payload) = auth_request.payload else {
             warn!(
                 event = "received auth request with empty payload",
-                "grpc.useragent.auth_adapter"
+                "grpc.operator.auth_adapter"
             );
             return None;
         };
@@ -140,12 +160,11 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
             AuthRequestPayload::ChallengeRequest(ProtoAuthChallengeRequest {
                 pubkey,
                 bootstrap_token,
-                ..
             }) => {
                 let Ok(pubkey) = authn::PublicKey::try_from(pubkey.as_slice()) else {
                     warn!(
                         event = "received request with invalid public key",
-                        "grpc.useragent.auth_adapter"
+                        "grpc.operator.auth_adapter"
                     );
                     return None;
                 };
@@ -163,12 +182,3 @@ impl Receiver<auth::Inbound> for AuthTransportAdapter<'_> {
 }
 
 impl Bi<auth::Inbound, Result<auth::Outbound, auth::Error>> for AuthTransportAdapter<'_> {}
-
-pub async fn start(
-    conn: &mut UserAgentConnection,
-    bi: &mut GrpcBi<UserAgentRequest, UserAgentResponse>,
-    request_tracker: &mut RequestTracker,
-) -> Result<authn::PublicKey, auth::Error> {
-    let transport = AuthTransportAdapter::new(bi, request_tracker);
-    auth::authenticate(conn, transport).await
-}

server/crates/arbiter-server/src/grpc/operator/evm.rs

@@ -1,3 +1,17 @@
+use crate::{
+    grpc::{
+        Convert, TryConvert,
+        common::inbound::{RawEvmAddress, RawEvmTransaction},
+    },
+    peers::operator::{
+        OperatorSession,
+        session::handlers::{
+            GrantMutationError, HandleEvmWalletCreate, HandleEvmWalletList, HandleGrantCreate,
+            HandleGrantDelete, HandleGrantList, HandleSignTransaction,
+            SignTransactionError as SessionSignTransactionError,
+        },
+    },
+};
 use arbiter_proto::proto::{
     evm::{
         EvmError as ProtoEvmError, EvmGrantCreateRequest, EvmGrantCreateResponse,
@@ -10,43 +24,29 @@ use arbiter_proto::proto::{
         wallet_create_response::Result as WalletCreateResult,
         wallet_list_response::Result as WalletListResult,
     },
-    user_agent::{
+    operator::{
         evm::{
             self as proto_evm, SignTransactionRequest as ProtoSignTransactionRequest,
             request::Payload as EvmRequestPayload, response::Payload as EvmResponsePayload,
         },
-        user_agent_response::Payload as UserAgentResponsePayload,
+        operator_response::Payload as OperatorResponsePayload,
     },
 };
+
 use kameo::actor::ActorRef;
 use tonic::Status;
 use tracing::warn;
 
-use crate::{
-    actors::user_agent::{
-        UserAgentSession,
-        session::connection::{
-            GrantMutationError, HandleEvmWalletCreate, HandleEvmWalletList, HandleGrantCreate,
-            HandleGrantDelete, HandleGrantList, HandleSignTransaction,
-            SignTransactionError as SessionSignTransactionError,
-        },
-    },
-    grpc::{
-        Convert, TryConvert,
-        common::inbound::{RawEvmAddress, RawEvmTransaction},
-    },
-};
-
-const fn wrap_evm_response(payload: EvmResponsePayload) -> UserAgentResponsePayload {
-    UserAgentResponsePayload::Evm(proto_evm::Response {
+const fn wrap_evm_response(payload: EvmResponsePayload) -> OperatorResponsePayload {
+    OperatorResponsePayload::Evm(proto_evm::Response {
         payload: Some(payload),
     })
 }
 
 pub(super) async fn dispatch(
-    actor: &ActorRef<UserAgentSession>,
+    actor: &ActorRef<OperatorSession>,
     req: proto_evm::Request,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let Some(payload) = req.payload else {
         return Err(Status::invalid_argument("Missing EVM request payload"));
     };
@@ -62,8 +62,8 @@ pub(super) async fn dispatch(
 }
 
 async fn handle_wallet_create(
-    actor: &ActorRef<UserAgentSession>,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+    actor: &ActorRef<OperatorSession>,
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let result = match actor.ask(HandleEvmWalletCreate {}).await {
         Ok((wallet_id, address)) => WalletCreateResult::Wallet(WalletEntry {
             id: wallet_id,
@@ -82,15 +82,15 @@ async fn handle_wallet_create(
 }
 
 async fn handle_wallet_list(
-    actor: &ActorRef<UserAgentSession>,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+    actor: &ActorRef<OperatorSession>,
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let result = match actor.ask(HandleEvmWalletList {}).await {
         Ok(wallets) => WalletListResult::Wallets(WalletList {
             wallets: wallets
                 .into_iter()
                 .map(|(id, address)| WalletEntry {
                     address: address.to_vec(),
-                    id,
+                    id: id.to_raw(),
                 })
                 .collect(),
         }),
@@ -107,8 +107,8 @@ async fn handle_wallet_list(
 }
 
 async fn handle_grant_list(
-    actor: &ActorRef<UserAgentSession>,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+    actor: &ActorRef<OperatorSession>,
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let result = match actor.ask(HandleGrantList {}).await {
         Ok(grants) => EvmGrantListResult::Grants(EvmGrantList {
             grants: grants
@@ -134,9 +134,9 @@ async fn handle_grant_list(
 }
 
 async fn handle_grant_create(
-    actor: &ActorRef<UserAgentSession>,
+    actor: &ActorRef<OperatorSession>,
     req: EvmGrantCreateRequest,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let basic = req
         .shared
         .ok_or_else(|| Status::invalid_argument("Missing shared grant settings"))?
@@ -164,9 +164,9 @@ async fn handle_grant_create(
 }
 
 async fn handle_grant_delete(
-    actor: &ActorRef<UserAgentSession>,
+    actor: &ActorRef<OperatorSession>,
     req: EvmGrantDeleteRequest,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let result = match actor
         .ask(HandleGrantDelete {
             grant_id: req.grant_id,
@@ -190,9 +190,9 @@ async fn handle_grant_delete(
 }
 
 async fn handle_sign_transaction(
-    actor: &ActorRef<UserAgentSession>,
+    actor: &ActorRef<OperatorSession>,
     req: ProtoSignTransactionRequest,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let request = req
         .request
         .ok_or_else(|| Status::invalid_argument("Missing sign transaction request"))?;

server/crates/arbiter-server/src/grpc/operator/governance.rs

@@ -0,0 +1,155 @@
+use crate::{
+    actors::proposal_manager::{Error as ProposalError, ProposalKind, VoteOutcome},
+    peers::operator::{
+        OperatorSession,
+        session::handlers::{HandleCastVote, HandleCreateProposal, HandleQueryPending},
+    },
+};
+use arbiter_proto::proto::operator::{
+    governance::{
+        self as proto_gov, CreateProposalRequest, QueryPendingRequest, QueryPendingResponse,
+        VoteOutcome as ProtoVoteOutcome, create_proposal_request::Kind as ProtoKind,
+        request::Payload as GovRequestPayload, response::Payload as GovResponsePayload,
+    },
+    operator_response::Payload as OperatorResponsePayload,
+};
+use kameo::actor::ActorRef;
+use tonic::Status;
+use tracing::warn;
+
+const fn wrap(payload: GovResponsePayload) -> OperatorResponsePayload {
+    OperatorResponsePayload::Governance(proto_gov::Response {
+        payload: Some(payload),
+    })
+}
+
+pub(super) async fn dispatch(
+    actor: &ActorRef<OperatorSession>,
+    req: proto_gov::Request,
+) -> Result<Option<OperatorResponsePayload>, Status> {
+    let Some(payload) = req.payload else {
+        return Err(Status::invalid_argument(
+            "Missing governance request payload",
+        ));
+    };
+
+    match payload {
+        GovRequestPayload::Create(req) => handle_create(actor, req).await,
+        GovRequestPayload::Vote(req) => handle_vote(actor, req).await,
+        GovRequestPayload::Query(QueryPendingRequest {}) => handle_query(actor).await,
+    }
+}
+
+async fn handle_create(
+    actor: &ActorRef<OperatorSession>,
+    req: CreateProposalRequest,
+) -> Result<Option<OperatorResponsePayload>, Status> {
+    let kind = match req.kind {
+        Some(ProtoKind::ApproveSdkClient(p)) => ProposalKind::ApproveSdkClient {
+            client_id: p.client_id,
+        },
+        Some(ProtoKind::GrantWalletAccess(p)) => ProposalKind::GrantWalletAccess {
+            wallet_id: p.wallet_id,
+            client_id: p.client_id,
+        },
+        Some(ProtoKind::ApproveServerUpdate(_)) => ProposalKind::ApproveServerUpdate,
+        Some(ProtoKind::ReplaceOperator(p)) => ProposalKind::ReplaceOperator {
+            old_operator_id: p.old_operator_id,
+            new_pubkey: p.new_pubkey,
+        },
+        Some(ProtoKind::UpdateShamirParameters(p)) => ProposalKind::UpdateShamirParameters {
+            #[expect(
+                clippy::cast_possible_truncation,
+                clippy::as_conversions,
+                reason = "new_n is always a small operator count"
+            )]
+            new_n: p.new_n as u8,
+        },
+        Some(ProtoKind::ApprovePersistentGrant(p)) => {
+            use prost::Message as _;
+            ProposalKind::ApprovePersistentGrant {
+                payload_bytes: p.encode_to_vec(),
+            }
+        }
+        Some(ProtoKind::ApproveOneOffTransaction(p)) => {
+            use prost::Message as _;
+            ProposalKind::ApproveOneOffTransaction {
+                payload_bytes: p.encode_to_vec(),
+            }
+        }
+        None => return Err(Status::invalid_argument("Missing proposal kind")),
+    };
+    let ttl_secs = req.ttl_secs.map(i64::from);
+
+    let proposal_id = actor
+        .ask(HandleCreateProposal { kind, ttl_secs })
+        .await
+        .map_err(|e| {
+            warn!(?e, "create_proposal failed");
+            Status::internal("Failed to create proposal")
+        })?;
+
+    Ok(Some(wrap(GovResponsePayload::Created(
+        proto_gov::CreateProposalResponse { proposal_id },
+    ))))
+}
+
+async fn handle_vote(
+    actor: &ActorRef<OperatorSession>,
+    req: proto_gov::CastVoteRequest,
+) -> Result<Option<OperatorResponsePayload>, Status> {
+    let result = actor
+        .ask(HandleCastVote {
+            proposal_id: req.proposal_id,
+            approve: req.approve,
+            signature: req.signature,
+        })
+        .await;
+
+    let outcome = match result {
+        Ok(VoteOutcome::Pending) => ProtoVoteOutcome::Pending,
+        Ok(VoteOutcome::QuorumApproved) => ProtoVoteOutcome::Approved,
+        Ok(VoteOutcome::QuorumRejected) => ProtoVoteOutcome::Rejected,
+        Err(kameo::error::SendError::HandlerError(ProposalError::AlreadyVoted)) => {
+            return Err(Status::invalid_argument("Already voted on this proposal"));
+        }
+        Err(kameo::error::SendError::HandlerError(ProposalError::InvalidSignature)) => {
+            return Err(Status::invalid_argument("Invalid vote signature"));
+        }
+        Err(kameo::error::SendError::HandlerError(ProposalError::ProposalNotFound)) => {
+            return Err(Status::not_found("Proposal not found"));
+        }
+        Err(e) => {
+            warn!(?e, "cast_vote failed");
+            return Err(Status::internal("Failed to cast vote"));
+        }
+    };
+
+    Ok(Some(wrap(GovResponsePayload::Voted(
+        proto_gov::VoteResponse {
+            outcome: outcome.into(),
+        },
+    ))))
+}
+
+async fn handle_query(
+    actor: &ActorRef<OperatorSession>,
+) -> Result<Option<OperatorResponsePayload>, Status> {
+    let summaries = actor.ask(HandleQueryPending {}).await.unwrap_or_default();
+
+    let proposals = summaries
+        .into_iter()
+        .map(|s| proto_gov::ProposalSummary {
+            id: s.id,
+            kind: s.kind,
+            initiator_id: s.initiator_id,
+            expires_at: s.expires_at.0.timestamp(),
+            approve_count: s.approve_count,
+            reject_count: s.reject_count,
+        })
+        .collect();
+
+    Ok(Some(wrap(GovResponsePayload::Pending(
+        QueryPendingResponse { proposals },
+    ))))
+}

server/crates/arbiter-server/src/grpc/operator/inbound.rs

@@ -1,26 +1,25 @@
-use alloy::primitives::{Address, U256};
-use arbiter_proto::proto::evm::{
-    EtherTransferSettings as ProtoEtherTransferSettings, SharedSettings as ProtoSharedSettings,
-    SpecificGrant as ProtoSpecificGrant, TokenTransferSettings as ProtoTokenTransferSettings,
-    TransactionRateLimit as ProtoTransactionRateLimit, VolumeRateLimit as ProtoVolumeRateLimit,
-    specific_grant::Grant as ProtoSpecificGrantType,
-};
-use arbiter_proto::proto::user_agent::sdk_client::{
-    WalletAccess, WalletAccessEntry as SdkClientWalletAccess,
-};
-use chrono::{DateTime, TimeZone, Utc};
-use prost_types::Timestamp as ProtoTimestamp;
-use tonic::Status;
-
-use crate::db::models::{CoreEvmWalletAccess, NewEvmWalletAccess};
-use crate::grpc::Convert;
 use crate::{
+    db::models::{CoreEvmWalletAccess, EvmWalletId, NewEvmWalletAccess},
     evm::policies::{
         SharedGrantSettings, SpecificGrant, TransactionRateLimit, VolumeRateLimit, ether_transfer,
         token_transfers,
     },
-    grpc::TryConvert,
+    grpc::{Convert, TryConvert},
 };
+use arbiter_proto::{
+    proto::evm::{
+        EtherTransferSettings as ProtoEtherTransferSettings, SharedSettings as ProtoSharedSettings,
+        SpecificGrant as ProtoSpecificGrant, TokenTransferSettings as ProtoTokenTransferSettings,
+        TransactionRateLimit as ProtoTransactionRateLimit, VolumeRateLimit as ProtoVolumeRateLimit,
+        specific_grant::Grant as ProtoSpecificGrantType,
+    },
+    proto::operator::sdk_client::{WalletAccess, WalletAccessEntry as SdkClientWalletAccess},
+};
+
+use alloy::primitives::{Address, U256};
+use chrono::{DateTime, TimeZone, Utc};
+use prost_types::Timestamp as ProtoTimestamp;
+use tonic::Status;
 
 fn address_from_bytes(bytes: &[u8]) -> Result<Address, Status> {
     if bytes.len() != 20 {
@@ -150,7 +149,7 @@ impl Convert for WalletAccess {
 
     fn convert(self) -> Self::Output {
         NewEvmWalletAccess {
-            wallet_id: self.wallet_id,
+            wallet_id: EvmWalletId::from_raw(self.wallet_id),
             client_id: self.sdk_client_id,
         }
     }
@@ -165,7 +164,7 @@ impl TryConvert for SdkClientWalletAccess {
             return Err(Status::invalid_argument("Missing wallet access entry"));
         };
         Ok(CoreEvmWalletAccess {
-            wallet_id: access.wallet_id,
+            wallet_id: EvmWalletId::from_raw(access.wallet_id),
             client_id: access.sdk_client_id,
             id: self.id,
         })

server/crates/arbiter-server/src/grpc/operator/outbound.rs

@@ -1,3 +1,8 @@
+use crate::{
+    db::models::EvmWalletAccess,
+    evm::policies::{SharedGrantSettings, SpecificGrant, TransactionRateLimit, VolumeRateLimit},
+    grpc::Convert,
+};
 use arbiter_proto::proto::{
     evm::{
         EtherTransferSettings as ProtoEtherTransferSettings, SharedSettings as ProtoSharedSettings,
@@ -5,17 +10,12 @@ use arbiter_proto::proto::{
         TransactionRateLimit as ProtoTransactionRateLimit, VolumeRateLimit as ProtoVolumeRateLimit,
         specific_grant::Grant as ProtoSpecificGrantType,
     },
-    user_agent::sdk_client::{WalletAccess, WalletAccessEntry as ProtoSdkClientWalletAccess},
+    operator::sdk_client::{WalletAccess, WalletAccessEntry as ProtoSdkClientWalletAccess},
 };
+
 use chrono::{DateTime, Utc};
 use prost_types::Timestamp as ProtoTimestamp;
 
-use crate::{
-    db::models::EvmWalletAccess,
-    evm::policies::{SharedGrantSettings, SpecificGrant, TransactionRateLimit, VolumeRateLimit},
-    grpc::Convert,
-};
-
 impl Convert for DateTime<Utc> {
     type Output = ProtoTimestamp;
 
@@ -103,7 +103,7 @@ impl Convert for EvmWalletAccess {
         Self::Output {
             id: self.id,
             access: Some(WalletAccess {
-                wallet_id: self.wallet_id,
+                wallet_id: self.wallet_id.to_raw(),
                 sdk_client_id: self.client_id,
             }),
         }

server/crates/arbiter-server/src/grpc/operator/sdk_client.rs

@@ -1,7 +1,18 @@
+use crate::{
+    db::models::NewEvmWalletAccess,
+    grpc::Convert,
+    peers::operator::{
+        OperatorSession, OutOfBand,
+        session::handlers::{
+            HandleGrantEvmWalletAccess, HandleListWalletAccess, HandleNewClientApprove,
+            HandleRevokeEvmWalletAccess, HandleSdkClientList,
+        },
+    },
+};
 use arbiter_crypto::authn;
 use arbiter_proto::proto::{
-    shared::ClientInfo as ProtoClientMetadata,
-    user_agent::{
+    operator::{
+        operator_response::Payload as OperatorResponsePayload,
         sdk_client::{
             self as proto_sdk_client, ConnectionCancel as ProtoSdkClientConnectionCancel,
             ConnectionRequest as ProtoSdkClientConnectionRequest,
@@ -13,32 +24,21 @@ use arbiter_proto::proto::{
             request::Payload as SdkClientRequestPayload,
             response::Payload as SdkClientResponsePayload,
         },
-        user_agent_response::Payload as UserAgentResponsePayload,
     },
+    shared::ClientInfo as ProtoClientMetadata,
 };
+
 use kameo::actor::ActorRef;
 use tonic::Status;
 use tracing::{info, warn};
 
-use crate::{
-    actors::user_agent::{
-        OutOfBand, UserAgentSession,
-        session::connection::{
-            HandleGrantEvmWalletAccess, HandleListWalletAccess, HandleNewClientApprove,
-            HandleRevokeEvmWalletAccess, HandleSdkClientList,
-        },
-    },
-    db::models::NewEvmWalletAccess,
-    grpc::Convert,
-};
-
-const fn wrap_sdk_client_response(payload: SdkClientResponsePayload) -> UserAgentResponsePayload {
-    UserAgentResponsePayload::SdkClient(proto_sdk_client::Response {
+const fn wrap_sdk_client_response(payload: SdkClientResponsePayload) -> OperatorResponsePayload {
+    OperatorResponsePayload::SdkClient(proto_sdk_client::Response {
         payload: Some(payload),
     })
 }
 
-pub(super) fn out_of_band_payload(oob: OutOfBand) -> UserAgentResponsePayload {
+pub(super) fn out_of_band_payload(oob: OutOfBand) -> OperatorResponsePayload {
     match oob {
         OutOfBand::ClientConnectionRequest { profile } => wrap_sdk_client_response(
             SdkClientResponsePayload::ConnectionRequest(ProtoSdkClientConnectionRequest {
@@ -59,9 +59,9 @@ pub(super) fn out_of_band_payload(oob: OutOfBand) -> UserAgentResponsePayload {
 }
 
 pub(super) async fn dispatch(
-    actor: &ActorRef<UserAgentSession>,
+    actor: &ActorRef<OperatorSession>,
     req: proto_sdk_client::Request,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let Some(payload) = req.payload else {
         return Err(Status::invalid_argument(
             "Missing SDK client request payload",
@@ -87,9 +87,9 @@ pub(super) async fn dispatch(
 }
 
 async fn handle_connection_response(
-    actor: &ActorRef<UserAgentSession>,
+    actor: &ActorRef<OperatorSession>,
     resp: ProtoSdkClientConnectionResponse,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let pubkey = authn::PublicKey::try_from(resp.pubkey.as_slice())
         .map_err(|()| Status::invalid_argument("Invalid ML-DSA public key"))?;
 
@@ -108,14 +108,14 @@ async fn handle_connection_response(
 }
 
 async fn handle_list(
-    actor: &ActorRef<UserAgentSession>,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+    actor: &ActorRef<OperatorSession>,
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let result = match actor.ask(HandleSdkClientList {}).await {
         Ok(clients) => ProtoSdkClientListResult::Clients(ProtoSdkClientList {
             clients: clients
                 .into_iter()
                 .map(|(client, metadata)| ProtoSdkClientEntry {
-                    id: client.id,
+                    id: client.id.to_raw(),
                     pubkey: client.public_key.clone(),
                     info: Some(ProtoClientMetadata {
                         name: metadata.name,
@@ -144,9 +144,9 @@ async fn handle_list(
 }
 
 async fn handle_grant_wallet_access(
-    actor: &ActorRef<UserAgentSession>,
+    actor: &ActorRef<OperatorSession>,
     req: ProtoSdkClientGrantWalletAccess,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+) -> Result<Option<OperatorResponsePayload>, Status> {
     let entries: Vec<NewEvmWalletAccess> = req.accesses.into_iter().map(Convert::convert).collect();
     match actor.ask(HandleGrantEvmWalletAccess { entries }).await {
         Ok(()) => {
@@ -161,9 +161,9 @@ async fn handle_grant_wallet_access(
 }
 
 async fn handle_revoke_wallet_access(
-    actor: &ActorRef<UserAgentSession>,
+    actor: &ActorRef<OperatorSession>,
     req: ProtoSdkClientRevokeWalletAccess,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+) -> Result<Option<OperatorResponsePayload>, Status> {
     match actor
         .ask(HandleRevokeEvmWalletAccess {
             entries: req.accesses,
@@ -182,8 +182,8 @@ async fn handle_revoke_wallet_access(
 }
 
 async fn handle_list_wallet_access(
-    actor: &ActorRef<UserAgentSession>,
-) -> Result<Option<UserAgentResponsePayload>, Status> {
+    actor: &ActorRef<OperatorSession>,
+) -> Result<Option<OperatorResponsePayload>, Status> {
     match actor.ask(HandleListWalletAccess {}).await {
         Ok(accesses) => Ok(Some(wrap_sdk_client_response(
             SdkClientResponsePayload::ListWalletAccess(ListWalletAccessResponse {