Cross Platform Programming

[NovaCoder]

I think you mean languages, in which case, yes lots of languages are portable and are supported on AmigaOS (classic).   The most common example is good on C, which in theory is protable by just a recompile (not actually true of course but it's a good story).

And yes new AmigaOS software is still being 'made'.

[NovaCoder]

Is there a way to go from Aros or Linux to Classic fairly easy?
I feel Hollywood was a good idea and maybe Xamos is a possible answer.

No, like I said it's not really that easy to do cross platform programming.   If I take a program written in C for Unix then sure I can get it working on Classic but only after replacing all the Unix specific functions, fixing up endian issues and replacing input, sound and video for AmigaOS equivalents.

Trouble with things like Holywood and SDL is that they are high level by design, this is fine if you have a lot to cycles to play with but on real classic hardware it's just too slow.