Add express
Add express

... and remove constraints for "speculate" and "extrapolate", fixing #4754.

athanclark/stackage,massysett/stackage,jonschoning/stackage,clinty/stackage,stackbuilders/stackage,simonmichael/stackage,Daniel-Diaz/stackage,fimad/stackage,soenkehahn/stackage,michalkonecny/stackage,mrkkrp/stackage,iand675/stackage,wereHamster/stackage,fpco/stackage,asr/stackage,spencerjanssen/stackage