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Swift Bitcoin aims to become the first Bitcoin full node implementation and library written entirely in Swift.

This repository contains a single Swift Package which exposes a series of library and executable products: crypto, base, wallet, blockchain, transport, RPC, node and utility.

Refer to each module's documentation to understand the exact functionality they each cover.

To integrate Swift Bitcoin into your Swift project add it to your Package.swift dependencies:

let package = Package( …
    dependencies: [ …
        .package(url: "https://github.com/swift-bitcoin/swift-bitcoin", branch: "develop") …

Then select the appropriate modules as dependencies for a specific target:

… targets: [
    .target( …
        dependencies: [ …
            .product(name: "BitcoinWallet", package: "swift-bitcoin") …

The umbrella module Bitcoin will make the entire framework available to your project.

.product(name: "Bitcoin", package: "swift-bitcoin") 

In your source files make sure to import the corresponding module:

import Bitcoin

Refer to this Getting Started documentation article to learn about some of the library's capabilities.

To build the project and run the command line tools use the swift command.

First make sure all tests are passing:

swift build --build-tests
swift test

Now you can run any of the executable targets available.

The Bitcoin Utility bcutil tool provides a number of useful offline commands as well as being able to query and control a running node instance. Check out the tool's help menu for usage information:

swift run bcutil --help

The Bitcoin Node bcnode tool launches a fresh node instance listening to RPC commands from bcutil node. Check out the tool's help menu for usage information:

swift run bcnode --help

Refer to this Building documentation article to learn how to produce a release build on multiple platforms.

Many of the latest features from the extended Swift Language ecosystem are leveraged by Swift Bitcoin to keep usability, performance and reliability at the highest possible level.

• Swift Package Manager
• C / C++ interoperability
• Async/await APIs
• Actors for mutable state isolation
• Non-Blocking I/O and service lifecycle
• Structured concurrency
• Data race safety
• Argument parser
• Swift Testing
• DocC documentation plugin
• Logging

Going forward we would like to experiment with Swift Macros, Swift Embedded and ~Copyable to bring the solution even closer to the cutting edge.

Swift Bitcoin itself depends on Bitcoin Core's libsecp256k1 as well as some official Swift Language packages that extend the standard library.

The transport component depends on the open source SwiftNIO library by Apple.

As of October 2024 the APIs for cryptography, hashing functions, encodings, transactions, scripting, verification, wallet addresses, key derivation and input signing are stable and tested.

Most if not all BIPs relating to transaction verification, SCRIPT and wallet have been implemented completely including official test vectors and test data borrowed from the Bitcoin Core project. This includes full segwit and taproot support.

Blockchain, mempool, coins view are working in-memory but their APIs have not yet been solidified.

At this time the peer-to-peer client is able to connect and perform an extended handshake, send and respond to pings and synchronize headers. It is not yet ready to fully synchronize against a testnet node or even a regtest node.

Make sure to check the project's blog for the latest news and updates.

The medium term focus is set on completing the wire protocol implementation on regtest.

After that the remaining BIPs associated to blocks and transport layer should be implemented.

Longer term a persistence story would need to be spec'd out and implemented to start thinking about sync'ing testnet.