Michoko Both Haxe and OpenFL are definitely mature enough to use in production, ultimately depending on your overall needs. Not to say their aren't caveats -- its open source, so of course it is perpetually an ongoing WIP, and bugs do arise. It's not however, lacking in many features, functionality, or overall stability. Versatility is virtually unmatched compared to Flash, considering you can target MacOS, Windows, Linux, HTML5, iOS, Android, and even consoles. The robust cross-platform ability does present some hardship in overall development of the openfl library and its dependencies from a maintaining standpoint. Most issues arise from far-edge cases and not typical usage.