Add constraint per matt-noonan/justified-containers#4
Add constraint per matt-noonan/justified-containers#4

stackbuilders/stackage,clinty/stackage,michalkonecny/stackage,creichert/stackage,mstksg/stackage,jonschoning/stackage,Daniel-Diaz/stackage,ethercrow/stackage,simonmichael/stackage,mrkkrp/stackage,fimad/stackage,wereHamster/stackage,massysett/stackage,athanclark/stackage,lwm/stackage,iand675/stackage,garetxe/stackage,soenkehahn/stackage,fpco/stackage,Shimuuar/stackage,peti/stackage,k0ral/stackage,asr/stackage,int-index/stackage,phaazon/stackage,spencerjanssen/stackage,mgajda/stackage