I've tried nearly all options listed on https://github.com/jashkenas/coffeescript/wiki/list-of-languages-that-compile-to-js, and I've spent about two weeks googling, but all that I've found have some combination of these problems:
- Whitespace-sensitive block scoping (coffeescript et al)
- Not actively maintained
- Interop is clunky
- Additional runtime needs to be loaded for the generated JS to work (traceur for example)
Initially coffeescript ticked all the boxes, but I don't like its var scoping, and personally I think the siginificant whitespace works everywhere except for closures, which I happen to use a lot. I realize this is a matter of preference, but my preference goes the other way. I'm open to pretty much any other syntax -- after trying to like coffeescript for a few weeks, I finally tried to get up to speed with lisp, but could not find one of those either that didn't hit on one of the above problems.