Lightweight, portable C++ fibers, MIT license

Question

I would like to get ahold of a lightweight, portable fiber lib with MIT license (or looser). Boost.Coroutine does not qualify (not lightweight), neither do Portable Coroutine Li

Answer 1

1. Libtask: MIT License
2. Libconcurrency: LGPL (a little tighter than MIT, but it's a functional library!)

Both are written for C.