Testnet compatibility is a mandatory milestone for any piece of Bitcoin-related software aiming to eventually reach production stage.

PSBT support as defined by BIP174 is an important feature to have for any Bitcoin SDK. It serves as a compatibility layer between different software implementations as well as dedicated hardware devices such as wallets and signers.

A cool feature of the Swift Package Manager (SPM) is how its package manifest format is itself part of the Swift Language. This is easier before compilation when the project's source code and the Swift compiler are at hand but can that approach be extended for compiled tools like bcnode?

One of the superpowers of Swift is the ability to define Domain Specific Languages (DSL) directly over the type system. That presented a great opportunity to have Bitcoin Miniscript implemented as a Swift DSL and have the compiler check its syntax entirely.

The /docs subfolder on this site is now generated independently from the main repo which means more frequent updates and accuracy in regards to the actual source code.

The new BinaryCodable framework adds simplicity, performance and stability to the way Bitcoin types are parsed and serialized from binary streams.

Creating meaningful unit tests can be difficult – even more when the system under test is a transport layer protocol like the Bitcoin wire protocol.

Happy 2025 to all Swift and Bitcoin devs! And Happy 16th Birthday to the Bitcoin network! I wanted to use the occasion for posting an update of where the project stands today and where it could go from here.

So far this year the focus has shifted a bit from getting the client fluent in the peer-to-peer language protocol to making important refinements to many of the public APIs offered by the package.

Last year the development of Swift Bitcoin really kicked off. All research work done on the swift-bitcoin-poc repo was carefully moved over and improved. This includes the transaction model and script engine with full segwit and taproot support.

The ultimate goal for Swift Bitcoin is to become the most comprehensive SDK for bitcoin in Swift with features like mempool management, block mining and connectivity via the bitcoin protocol.

Swift Bitcoin aka The Swift Bitcoin Library is a new project intended for Swift developers who want to build a bitcoin product.