After a year of development, Apple released the update of the Swift v. 5. Official builds are prepared for Linux (Ubuntu 14.04, 16.04, 18.04) and macOS (Xcode). The source code is distributed under the Apache 2.0 license.
The new version has ABI stabilized for macOS, iOS, tvOS and watchOS platforms. It is possible to deliver new versions of libraries without recompiling applications. In the standard library, the internal representation of strings is translated to UTF-8 encoding. Improved support for raw text (with special characters and line breaks) in string literals. New type for Result error handlers and SIMD vector type added. The possibilities for interpolating strings with the String type (text selection from arbitrary data) are expanded. The performance of the Dictionary and Set types has been increased.
The package manager provides support for mirroring dependencies, associating assembly parameters with a target platform, generating coverage data, and defining custom requirements for supported target platforms. The ability to import libraries into the REPL without assembly in the format of executable files has been added to the "swift run" command.
Get more info at official website.