I've personally had a very good experience with Haxe and Haxeflixel (https://haxeflixel.com/ https://haxeflixel.com/) although Heaps (https://heaps.io/ https://

I've personally had a very good experience with Haxe and Haxeflixel (https://haxeflixel.com/ https://haxeflixel.com/) although Heaps (https://heaps.io/ https://heaps.io/) seems to be more popular nowadays. Haxe is very nice as a language, can easily cross-compile to a lot of targets, Haxeflixel is heavily inspired by some Actionscript framework and has a lot of goodies. Maybe Heaps is more mature, up to date and allows for more advanced features. The cool thing is you can get started right away writing code, without having to learn a full-on tool like Unity. But it has visual tools for debugging things on-screen for example.