@michal_atlas @daviwil you can use r7rs by starting guile with --r7rs, or in the repl with
> ,use (scheme)
> (install-r7rs!)
Guile's r7rs and r6rs support is pretty good, but not complete, and there are some tiny divergences you have to figure out. But its good enough to build akku.
@michal_atlas @daviwil (if you're interested in r7rs in particular, which is generally pretty portable, I'd recommend going with an r7rs implementation like Chibi, and using akku to sort out the cross-implementation compatibility for you)