The best alternatives to Swifty Compiler are Swift Playgrounds, 100 Days of Swift, and Swift AI. If these 3 options don't work for you, we've listed a few more alternatives below.
Swift Playgrounds is a development environment for Swift created by Apple Inc. The original macOS version of Playgrounds, launched as an integrated part of Xcode, was announced and released by Apple Inc. in June 2, 2014 during WWDC 2014