Because of the nature of Rust tests, the nutshell integration test has a race condition. Triggering the issue in the local environment was hard, but it happens more often in #509 because all the keys are read from memory without blocking the database. The error happens because, by default, Rust tests run in parallel, and maybe by design or by mistake, the external wallet did not increase its counter until the completion of the minting. This led to some tests having the same blinded messages, and the fastest test would mint successfully. The slowest test would result in the CDK failing to sign duplicated blinded messages. In any case, the fix is on the rust side, running the tests sequentially.
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-redb: Redb Storage backend.
- cdk-rexie: Rexie Storage backend for browsers.
- 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.
- 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
Code Style Guidelines
-
Large Enum Variants: When an enum variant contains a large type (>100 bytes), box it using
Box<T>to reduce the overall enum size. This improves memory efficiency, especially for error types.// Instead of this: enum Error { SomeLargeError(LargeType), // LargeType is >100 bytes } // Do this: enum Error { SomeLargeError(Box<LargeType>), }
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][21] | Clear Authentication | ✔️ |
| [22][22] | Blind Authentication | ✔️ |
Bindings
Experimental JS bindings can be found in the bindings repository.
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.