Swift 4.1 Release Process

Swift 4.1 is a source compatible update to Swift 4.0. It will contain a few additive enhancements to the core language as well as improvements to the Swift Package Manager, Swift on Linux, and general quality improvements to the compiler and Standard Library.

→ swift.org/blog/swift-4.1-release-process/

Swift 4.1 is a source-compatible update to Swift 4.0 that adds minor language enhancements, improves the Swift Package Manager and Linux support, and includes quality fixes to the compiler and standard library, but it lacks binary compatibility due to ABI stabilisation work for Swift 5.

The release targets the first half of 2018, with the swift-4.1-branch starting from master on October 18, 2017, regular merges every two weeks until the final cutoff on December 4, 2017, after which only critical fixes enter via pull requests.

Changes must align with Swift Evolution for language and APIs, with increasingly strict criteria as the release nears, and pull requests require detailed explanations, risk assessments, and reviews by release managers. Downloadable snapshots will post regularly from the branch for testing.