Hi, I'm trying to package ghc-sdl2, but have hit a problem with requirements I don't understand how to get past. The work so far can be seen and downloaded from https://notabug.org/thomassgn/guixsd-configuration/src/master/modules/ton-haskell.scm As you can see I have made some hackery with versions, e.g. the 'ghc-test-framework-quickcheck2-w-qc-2.9' package. And this is where I am stuck now. The thing is that somewhere down the line I get (this is from 'guix build ghc-linear'): ----- src/Linear/V1.hs:132:10: error: • No instance for (semigroupoids-5.1:Data.Semigroup.Foldable.Class.Foldable1 V1) arising from the superclasses of an instance declaration ----- So I packaged semigroupoids-5.2.2 which has this thing the error above is pointing at. But semigroupoids-5.1 is still pulled in and used by something else in my buildgraph. So first I need to figure out what. And then I need some way of making that thing use semigroupoids-5.2.2 instead. Or maybe there is something else entirely I can or should do to solve this. I don't know much haskell. Started packaging this for someone asking on IRC some weeks ago. Very interesting and rewarding until I ht this wall, but hope I can get past it now :) -- I use gpg to sign my emails. All the symbols you may see at the bottom of this mail is my cryptographic signature. It can be ignored, or used to check that it really is me sending this email. Learn more by asking me or see: https://u.fsf.org/zb or https://ssd.eff.org/