Last year in September 2017, Swift 4.0 was released. Ahead of the planned release of Swift 5 in 2019, Apple released Swift 4.2 It brings a major update from Swift 4.0 and Swift 4.1The good news is, you can now use Xcode 10.0 in order to build targets written in Swift 4 or Swift 3. The current version brings the Swift programming language closer to a stabilized application binary interface or ABI. This in turn enables binary compatibility for future releases.As a Swift app development company, we know that the current Swift 4.2 is not binary-compatible with previous releases, even though Apple’s primary goal is stability. However, source compatibility has been provided. Most of the source code built with the new Swift 4.0 compiler should easily compile with Swift 4.1 and Swift 4.2 compilers.