The Clojure version has a naming inconsistency: The expected function is called "duration" in the code and test, but the submission requires it to be called "formatDuration"

Maybe it's possible to hide +? Or redefine it to a binary method to be able to use it?

This looks interesting, but I'm struggling to understand the Poker rules.

The Wikipedia link shows 5-card hands and explains their ranking. But the tests seem to also test for 7-card hands. How do all those concepts translate? Is there a 3 pair, for example?

Also, the second big hand should probably read "8C 6C 5C JC 7C 9C 10C" (instead of "8C 4..") so that it is actually a straight.

I when trying to submit, my solution produces an
Test.hs: out of memory (requested 1048576 bytes)
error with no furher information on what the inputs are that triggered it.

Any ideas what might cause that or how to approach fixing it?

Duplicate of http://www.codewars.com/kata/525f4206b73515bffb000b21 "Adding Big Numbers"