Drops irpc from alknet-vault entirely. The vault's dispatch is now direct method calls on VaultServiceHandle — no VaultProtocol enum, no VaultMessage, no VaultServiceActor, no mpsc channel, no Service trait, no RemoteService trait, no postcard serialization. The vault is local-only by construction. The core security argument: irpc made the vault remote-capable by default (RemoteService generated unless no_rpc is passed). The IrohProtocol handler forwards all messages without auth. The docs framed 'register an ALPN' as a server-setup change. This is the default-insecure anti-pattern — security should be opt-in, not opt-out. ADR-025 inverts the default: local-only is the only mode, and remote access requires building a separate vault-server crate (a visible architectural act, not a flag flip). The actor path was already dead code — service.md said 'prefer VaultServiceHandle directly — no channel, no serialization.' The actor existed only to make irpc's Service trait work, which existed only to make RemoteService work, which was the footgun. VaultServiceHandle's Arc<RwLock> provides concurrent reads and exclusive writes — better throughput than the actor's sequential processing. DerivedKey serialization simplifies: always redact on serialize (for logging safety), reject '[REDACTED]' on deserialize with an error. No 'postcard preserves bytes' path. This resolves review #002 W8 (silent corruption on JSON-deserialized DerivedKey). Resolves: - OQ-21: remote vault access — resolved (not deferred). Not a vault crate feature; if needed, a separate vault-server crate with its own ADR. - C7: vault-server-crate question decided — not created now, not precluded. - C8: operation access policy table dissolved — all operations local-only by default; if a vault-server crate exposes some remotely, that crate defines the policy. - W8: DerivedKey JSON deserialization — resolved (reject redacted payloads). Amends ADR-005 (irpc remains for alknet-call, not for alknet-vault), ADR-018 (vault is even more standalone — zero RPC framework deps), ADR-019 (vault is the only layer, not just the only direct-caller layer), ADR-008 (vault integration point unchanged, but now local-only by construction).
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status, last_updated
| status | last_updated |
|---|---|
| draft | 2026-06-22-20 |
Alknet Architecture
Current State
Pre-implementation. The project has completed a pivot from a three-layer model to an ALPN-as-service model. The greenfield workspace contains only alknet-vault (stable — implementation exists, pending ADR-025 refactor to drop irpc) and research/reference material. Foundational ADRs (001–025) are in place, including the BiStream type definition (ADR-007), vault integration (ADR-008), ALPN router/endpoint (ADR-010), AuthContext structure (ADR-011), call protocol stream model (ADR-012), Rust as canonical implementation language (ADR-013), secret material flow with capability injection (ADR-014), privilege model with authority context (ADR-015), abort cascade for nested calls (ADR-016), call protocol client and adapter contract (ADR-017), vault standalone crate (ADR-018), vault assembly-layer-only access (ADR-019), HD derivation for encryption keys (ADR-020), key rotation via version-indexed paths (ADR-021), handler registration, provenance, and composition authority (ADR-022), operation error schemas (ADR-023), operation registry layering (ADR-024), and vault local-only dispatch (ADR-025). ADR-024 resolves the registry mutability question (from_call imports require a runtime-mutable home) and the OperationContext.env type identity crisis (review #002 C6), by layering the registry by trust boundary and making OperationEnv a trait-object integration point. ADR-025 drops irpc from the vault, making it local-only by construction (inverting the security default from remote-capable-by-default to local-only-by-default) and resolving OQ-21, C7, C8, and W8. The alknet-core, alknet-call, and alknet-vault crate specs are in draft.
Next step: Continue working through review #002's remaining Tier 4 findings (vault security decisions, guard clauses, ADR-writing exercises, smaller spec decisions). All open questions for the core and call crates are resolved; the vault crate's OQ-21 (remote vault) is now resolved (ADR-025 — vault is local-only by construction).
Architecture Documents
| Document | Status | Description |
|---|---|---|
| overview.md | draft | Workspace-level overview, crate graph, shared types, design principles |
| open-questions.md | draft | Centralized OQ tracker with door-type classifications |
| crates/core/README.md | draft | alknet-core crate index |
| crates/core/core-types.md | draft | ProtocolHandler, HandlerError, Connection, BiStream, StreamError |
| crates/core/endpoint.md | draft | ALPN router, HandlerRegistry, accept loop, shutdown |
| crates/core/auth.md | draft | AuthContext, Identity, IdentityProvider, AuthToken, resolution flow |
| crates/core/config.md | draft | StaticConfig, DynamicConfig, ArcSwap, ConfigReloadHandle |
| crates/call/README.md | draft | alknet-call crate index |
| crates/call/call-protocol.md | draft | CallAdapter, EventEnvelope framing, stream model, PendingRequestMap, bidirectional calls, streaming subscribe example |
| crates/call/operation-registry.md | draft | OperationSpec, Handler, OperationRegistry, AccessControl, capability injection, service discovery, irpc integration |
| crates/vault/README.md | draft | alknet-vault crate index |
| crates/vault/mnemonic-derivation.md | draft | BIP39, SLIP-0010, BIP-0032, derivation paths, key types |
| crates/vault/encryption.md | draft | AES-256-GCM, EncryptedData, key versioning, salt (Phase B reserved) |
| crates/vault/service.md | draft | VaultServiceHandle lifecycle, actor dispatch, cache, error model |
| crates/vault/protocol.md | draft | DerivedKey redaction, KeyType, serialization behavior |
ADR Table
| ADR | Title | Status |
|---|---|---|
| 001 | ALPN-Based Protocol Dispatch | Accepted |
| 002 | ProtocolHandler Trait | Accepted |
| 003 | Crate Decomposition | Accepted |
| 004 | Auth as Shared Core (IdentityProvider) | Accepted |
| 005 | irpc as Call Protocol Foundation | Accepted |
| 006 | ALPN String Convention and Connection Model | Accepted |
| 007 | BiStream Type Definition | Accepted |
| 008 | Vault Integration Point | Accepted |
| 009 | One-Way Door Decision Framework | Accepted |
| 010 | ALPN Router and Endpoint | Accepted |
| 011 | AuthContext Structure and Resolution Flow | Accepted |
| 012 | Call Protocol Stream Model | Accepted |
| 013 | Rust as Canonical Implementation Language | Accepted |
| 014 | Secret Material Flow and Capability Injection | Accepted |
| 015 | Privilege Model and Authority Context | Accepted |
| 016 | Abort Cascade for Nested Calls | Accepted |
| 017 | Call Protocol Client and Adapter Contract | Accepted |
| 018 | Vault as Standalone Crate | Accepted |
| 019 | Vault Assembly-Layer-Only Access | Accepted |
| 020 | HD Derivation for Encryption Keys | Accepted |
| 021 | Key Rotation via Version-Indexed Paths | Accepted |
| 022 | Handler Registration, Provenance, and Composition Authority | Accepted |
| 023 | Operation Error Schemas | Accepted |
| 024 | Operation Registry Layering | Accepted |
| 025 | Vault Local-Only Dispatch | Accepted |
Open Questions
See open-questions.md for the full tracker.
Resolved one-way doors:
- OQ-01: BiStream type — trait with Connection parameter (ADR-007)
- OQ-02: AuthContext timing — hybrid model (ADR-004)
- OQ-03: ALPN naming —
alknet/prefix, no version (ADR-006) - OQ-05: Multi-connectivity endpoint — quinn + iroh, both feature-gated (ADR-010)
- OQ-06: ALPN per connection, not per stream (ADR-006)
- OQ-08: Vault integration — CLI-embedded, assembly-layer only (ADR-008, ADR-014)
- OQ-16: Safe vault operations for call protocol exposure — none for now (ADR-014)
- OQ-18: Privilege model —
internal= authority switch, External/Internal visibility, handler identity + scoped env (ADR-015) - OQ-17: Abort cascade —
call.abortedcascades to descendants; defaultabort-dependents,continue-runningopt-in (ADR-016) - OQ-15: Call protocol client and adapter contract —
CallClientopens connections;from_callimports remote ops; connection direction independent of call direction (ADR-017)
Resolved two-way doors:
- OQ-04: Dynamic handler registration — static at startup (ADR-010); scoped to the
HandlerRegistry(ALPN-level) by ADR-024, which governsOperationRegistrymutability separately - OQ-07: Call protocol scope — bidirectional streams, EventEnvelope, ID-based correlation (ADR-012)
- OQ-11: Handler-level auth resolution observability — handlers store resolved identity on Connection (Option B); two identity scopes: connection-level (observability) and per-request (ACL)
- OQ-12: TLS identity provisioning — two use cases: RFC 7250 raw keys (default, P2P) and X.509 certs (domain-hosted, browsers). ACME is a proven pattern.
- OQ-13: Operation path format —
/{service}/{op}is the correct design for alknet-call, not a simplification - OQ-14: Batch operation semantics — multiple correlated
call.requestedevents is the correct protocol design, not a simplification - OQ-19: Session-scoped registries — agent-written operations via
OperationEnvtrait layering; protocol doesn't need changes;OperationEnvmust remain a trait. Generalized by ADR-024 to cover connection-scoped overlays as well. - OQ-20: Encryption key derivation — HD derivation from BIP39 seed, not PBKDF2; salt field unused in v2 (wire-format compat) (ADR-020)
- OQ-21: Remote vault access — resolved (ADR-025): vault is local-only by construction; remote access requires a separate vault-server crate with its own ADR
- OQ-22: Key rotation — version-indexed derivation paths;
rotatemethod re-encrypts (ADR-021) - OQ-23: Handler identity registration path — registration bundle with provenance, composition authority, scoped env, capabilities (ADR-022)
- OQ-24: Operation error schemas — declared domain errors with typed
detailspayload; adapter fidelity forfrom_openapi/to_openapi(ADR-023)
Deferred (not active):
- OQ-09: WASM target boundaries — design constraint, not deliverable
- OQ-10: Git adapter scope — start with smart protocol, add ERC721 later
Document Lifecycle
| Status | Meaning | Transitions |
|---|---|---|
draft |
Under active development. May change significantly. | → reviewed when open questions are resolved |
reviewed |
Architecture is final. Implementation may begin. Changes require review. | → stable when implementation is complete and verified |
stable |
Locked. Changes require review and may warrant an ADR. | → deprecated when superseded |
deprecated |
Superseded. Kept for reference. | Removed when no longer referenced |
References
- Pivot proposal:
docs/research/pivot/alpn-service-architecture.md - Cleanup plan:
docs/research/pivot/cleanup-plan.md - SDD process:
docs/sdd_process.md - Reference implementation:
/workspace/@alkdev/alknet-main/