I'm a haxe user. What exactly are you wanting to know? If by reliability you are talking about it consistently not breaking between versions, then it's fine.

I'm a haxe user. What exactly are you wanting to know? If by reliability you are talking about it consistently not breaking between versions, then it's fine. Between versions the compiler does add new features but for the most part backwards compatibility has been kept between major versions. If you're talking about does it consistently produce similar code across platforms, then it depends. Plenty of people are using it for 2D games (targetting flash, Android and iOS) and it seems suitable for this. Outside of that, it basically comes down to this: if you want your code to work cross platform, stick to the standard library or to known cross-platform libraries. As an example, I had a piece of code which took markdown text input, converted it to HTML, and then manipulated the resulting HTML. The code worked on Javascript, Neko and CPP without modifications, because I stuck to existing cross platform libraries.