Online judges

From HaskellWiki

Among many Online judges and competitive coding sites there are some that support Haskell, listed in following table.

Site GHC version
HackerRank 8.6.3
Kattis 8.4.4
CodinGame 8.4.3
CodeWars 8.2.2
CodeChef 8.0.1
CodeForces 7.8.3
HackerEarth 7.6.3
CodeFights 7.6.3
devdraft 7.6
exercism.io Multiple version (using stack)
codeabbey (unknown)
edufyme (unknown)