Third wallet-handler slice. Authenticated, view-only proxies over the
GrinClient — the backend holds no Grin spend key; the wallet exports its
rewind_hash (a public-derived view credential) per scan, the backend forwards
it to grin-wallet's scan_rewind_hash and stores no secret. Spending happens in
the wallet; the backend only broadcasts the finalized tx.
Endpoints (under /api/v1/wallet/grin):
- POST scan {rewind_hash, start_height?} -> {outputs, total_balance,
last_pmmr_index} (incremental resume index)
- GET height -> {height}
- POST broadcast {tx} -> {ok} (node push_transaction)
- JWT-gated. rewind_hash is a view credential: GrinScanRequest omits Debug and
is skipped from every span (never logged), and is validated as 64 hex before
any grin call (applying the wallet-handler review's secret-DTO lesson).
- Feature-gated: grin disabled -> 400.
- Shared validate_hex64 in wallet/mod.rs (view_key + rewind_hash); 3 paths +
schemas + grin tag registered; spec regenerated, drift-clean.
4 L1 integration tests (auth gate on scan/height/broadcast; malformed
rewind_hash 400).
Also: dropped Debug from the xmr_wow view_key-bearing request DTOs
(ViewRequest/RegisterRequest) per the review — defense-in-depth against a
cleartext view_key dump.
smirk-backend-core
Open, self-hostable backend for the Smirk non-custodial, multi-chain wallet. It provides the chain-access and identity surface a Smirk wallet needs — authentication, per-chain wallet access (Bitcoin, Litecoin, Monero, Wownero, Grin), the Grin slatepack relay, and Nostr-based identity — so anyone can run their own backend and a Smirk wallet can connect to it.
Status: early, under active development. Interfaces and the database schema may change before the first tagged release. Not yet recommended for production self-hosting.
What it is
- Non-custodial. The server never holds spend keys or seeds. It brokers access to blockchain data and relays wallet-to-wallet messages.
- Open core, feature-flagged. Every feature ships in this codebase and is
toggled per deployment; the wallet reads
GET /api/v1/capabilitiesand adapts to what a given backend offers. - Identity via "Sign in with Smirk". Authentication uses a seed-derived Nostr key (NIP-98); the server stores only public keys.
- Privacy first. No PII is required to use it; operator and user privacy are explicit design goals.
Architecture
Rust + Axum, PostgreSQL via sqlx. The public HTTP contract is generated from the handlers with utoipa (OpenAPI), which in turn drives the wallet's generated TypeScript client — one source of truth, checked for drift in CI.
Quickstart
cp .env.example .env # then fill in DATABASE_URL, JWT_SECRET, node URLs
cargo run # starts the API server
A full self-hosting guide (node requirements, reverse proxy, Tor admin onion,
backups) will live in docs/ as it stabilises.
Security
Please report vulnerabilities privately — see SECURITY.md. Do not open public issues for security reports.
License
To be finalized (MIT vs AGPL-3.0-or-later). Until a LICENSE file is added,
all rights are reserved.