bdk-floresta

A Floresta-powered chain-source crate for BDK.

Synopsis

This crate is a novel chain-source crate implementation meant for wallet applications built with BDK, allowing for zero-trust and completely local wallet synchronization, by embedding a lightweight full node direcly inside a wallet application.

By leveraging Utreexo and Floresta, it's possible to implement a lightweight full node with minimal resource requirements, making it possible for every wallet to have it's own node.

Developing

This project uses cargo-rbmt to manage everything related to cargo, such as formatting, linting, testing and CI. To install it, run:

% cargo install cargo-rbmt

A justfile is provided for convenience. Run just to see available commands:

% just
> bdk-floresta
> A Floresta-powered chain-source crate for BDK

> Available recipes:
    build                 # Build `bdk-floresta` and examples [alias: b]
    check                 # Check code formatting, compilation, linting, and commit signature [alias: c]
    check-features        # Check that all feature combinations compile
    check-sigs            # Checks whether all commits in this branch are signed
    delete item="example" # Delete files: example, target, lockfiles [alias: d]
    doc                   # Generate documentation
    doc-open              # Generate and open documentation
    example name="node"   # Run an example crate [alias: e]
    fmt                   # Format code [alias: f]
    lock                  # Regenerate `Cargo-recent.lock` and `Cargo-minimal.lock`
    msrv                  # Verify the library builds with MSRV (1.85.0)

Architecture

This crate is implemented on top of libfloresta, a set of libraries for building lightweight Bitcoin nodes, and is composed of two main components: the Builder and the Node.

Wallet updates can either stem from new blocks that the Node validates, which can then be applied to the wallet, or from a blockchain scan using Compact Block Filters.

libfloresta

The crates below are used to implement the Node:

• floresta-chain: Implements the Node's chain state, and validates blocks and transactions.

• floresta-compact-filters: Implements a storage mechanism for Compact Block Filters, used to figure out which blocks to request from the P2P network to update the wallet.

• floresta-mempool: Implements the Node's mempool, used to relay and cache transactions, as well as generating fee estimates.

• floresta-wire: Implements all of the Node's peer-to-peer logic.

Minimum Supported Rust Version (MSRV)

This library should compile with any combination of features on Rust 1.85.0.

To build with the MSRV toolchain, copy Cargo-minimal.lock to Cargo.lock.

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.