The latest significant advancement in the Swift programming language came with Swift 3. However, the introduction of Swift 6 brings a comprehensive set of changes that easily surpass Swift 3. This upgrade incorporates numerous new features and includes changes from previous versions that were previously hidden behind flags but will now be enabled by default in version 6. Consequently, many enhancements might not immediately catch the eye of developers.
Ted Kremenek, Apple's Director of Languages and Runtimes, praised the launch of Swift 6, suggesting that Swift is the optimal programming language to replace C++. According to Kremenek, "The safety, speed, and user-friendliness of Swift, coupled with its integrated C and C++ interoperability, make Swift the ideal successor to C++."
Kremenek also revealed that Swift 6 had undergone years of development. At the conference, he emphasized a significant new feature: compile-time data race safety, which is optional due to its disruptive nature. He also touched upon Embedded Swift, a subset of Swift designed for microcontrollers and other embedded systems.