Previously, we fetched the initial state *before* registering the new subscription. Any events emitted after the DB read but before the subscription was installed were dropped—most visible under low-resource conditions (e.g., CI). Change: - Register the subscription first, then asynchronously fetch and send the initial state (spawned task). This eliminates the window where events could be missed. - Require `F: Send + Sync` and store `on_new_subscription` as `Arc<F>` so it can be safely used from the spawned task. Result: - No gap between “subscribe” and “start receiving,” avoiding lost events. - Initial state still delivered, now via a background task.
Warning
This project is in early development, it does however work with real sats! Always use amounts you don't mind losing.
Cashu Development Kit
CDK is a collection of rust crates for Cashu wallets and mints written in Rust.
ALPHA This library is in early development, the api will change and should be used with caution.
Project structure
The project is split up into several crates in the crates/ directory:
- Libraries:
- cdk: Rust implementation of Cashu protocol.
- cdk-sqlite: SQLite Storage backend.
- cdk-postgres: PostgreSQL Storage backend.
- cdk-redb: Redb Storage backend.
- cdk-axum: Axum webserver for mint.
- cdk-cln: CLN Lightning backend for mint.
- cdk-lnd: Lnd Lightning backend for mint.
- cdk-lnbits: LNbits Lightning backend for mint. Note: Only LNBits v1 API is supported.
- cdk-ldk-node: LDK Node Lightning backend for mint.
- cdk-fake-wallet: Fake Lightning backend for mint. To be used only for testing, quotes are automatically filled.
- cdk-mint-rpc: Mint management gRPC server and cli.
- Binaries:
- cdk-cli: Cashu wallet CLI.
- cdk-mintd: Cashu Mint Binary.
- cdk-mint-cli: Cashu Mint management gRPC client cli.
Development
For a guide to settings up a development environment see DEVELOPMENT.md
LDK Node Network Configuration
For detailed configuration examples for running CDK with LDK Node on different Bitcoin networks (Mutinynet, Testnet, Mainnet), see LDK Node Network Guide.
Quick Start with Mutinynet (Recommended for Testing):
[ln]
ln_backend = "ldk-node"
[ldk_node]
bitcoin_network = "signet"
esplora_url = "https://mutinynet.com/api"
rgs_url = "https://rgs.mutinynet.com/snapshot/0"
gossip_source_type = "rgs"
Implemented NUTs:
Mandatory
| NUT # | Description |
|---|---|
| 00 | Cryptography and Models |
| 01 | Mint public keys |
| 02 | Keysets and fees |
| 03 | Swapping tokens |
| 04 | Minting tokens |
| 05 | Melting tokens |
| 06 | Mint info |
Optional
| # | Description | Status |
|---|---|---|
| 07 | Token state check | ✔️ |
| 08 | Overpaid Lightning fees | ✔️ |
| 09 | Signature restore | ✔️ |
| 10 | Spending conditions | ✔️ |
| 11 | Pay-To-Pubkey (P2PK) | ✔️ |
| 12 | DLEQ proofs | ✔️ |
| 13 | Deterministic secrets | ✔️ |
| 14 | Hashed Timelock Contracts (HTLCs) | ✔️ |
| 15 | Partial multi-path payments (MPP) | ✔️ |
| 16 | Animated QR codes | ❌ |
| 17 | WebSocket subscriptions | ✔️ |
| 18 | Payment Requests | ✔️ |
| 19 | Cached responses | ✔️ |
| 20 | Signature on Mint Quote | ✔️ |
| 21 | Clear Authentication | ✔️ |
| 22 | Blind Authentication | ✔️ |
| 23 | Payment Method: BOLT11 | ✔️ |
| 25 | Payment Method: BOLT12 | ✔️ |
License
Code is under the MIT License
Contribution
All contributions are welcome.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, shall be licensed as above, without any additional terms or conditions.
Please see the development guide.