Such as: 

fgl https://web.engr.oregonstate.edu/~erwig/fgl/haskell/

WWWBrowser https://cth.altocumulus.org/~hallgren/wwwbrowser.html

Balsa/Teak (languages) http://apt.cs.manchester.ac.uk/projects/tools/balsa/

BlueSpec compiler https://github.com/B-Lang-org/bsc

The CABAL spec (Common Architecture for Building Applications and Tools) https://www.haskell.org/cabal/proposal/index.html

Frag (that one Haskell game) https://wiki.haskell.org/Frag

Hugs string extensions https://www.haskell.org/hugs/pages/users_guide/here-documents.html

I guess darcs/c2hs/happy/alex count, they have history! 

Bonus points for