Apple

The XCTest Project, A Swift core library for providing unit test support

The Swift Programming Language

This is the version of LLDB that supports the Swift programming language & REPL.

The Foundation Project, providing core utilities, internationalization, and OS independence

The Package Manager for the Swift Programming Language

This maintains proposals for changes and user-visible enhancements to the Swift Programming Language.

Python Kerberos library used by CalendarServer

Logging and communication to allow Swift toolchains to communicate with Xcode.

Automated tests for validating the generated Swift snapshots behave correctly

The libdispatch Project, (a.k.a. Grand Central Dispatch), for concurrency on multicore hardware

A low-level build system, used by Xcode 9 and the Swift Package Manager

Plugin and runtime library for using protobuf with Swift

The infrastructure and project index comprising the Swift source compatibility suite.

Example package for use with the Swift Package Manager

Official CUPS Sources

The Calendar and Contacts Server.

Moved to apple/swift-protobuf

The Darwin Platform Library (mirror)

The Darwin PThread Library (mirror)

The Darwin Kernel (mirror)

CalDAV/CardDAV Testing Tool Used by CalendarServer

Python Framework for macOS APIs used by CalendarServer

Twisted SecureTransport library used by CalendarServer

Python iCalendar library used by CalendarServer

Extensions to Twisted used by CalendarServer