Factor practice challenges – train on code kata
www.codewars.com
Practice Factor coding with code challenges designed to engage your programming skills. Solve coding problems and pick up new techniques from your fellow peers.

Forth, too.

Unfortunately it uses the stable Factor release 0.98 which is a bit old, but I know Factor is heading toward a new release soon, which is probably a prerequisite to updating the runtime on Codewars.

Anyway the little exercises help me get to know the language, and then when I see others’ solutions I get to see how badly I’ve done things and what cool library words I should learn next.

Anyone else using a concatenative language on an exercises-type site like this, especially where other solutions in the same language can be shared?