Comment by AndruLuvisi

Original author here. Funny you should mention that. I once made an attempt to do the same. You can find it at http://web.sonoma.edu/users/l/luvisi/scheme/prog.scm

One fun thing about this implementation is that labels can be passed to other functions, or returned from functions, and even used to jump back into functions that have already exited, since they are based on continuations.

Good luck!