Rebranding head.hackage

Teo Camarasu
2025-09-14T08:08:20Z

I don't think this is a priority, but an issue I often face when talking to people about head.hackage is that they misunderstand what it is.

I think the prevailing impression is that it is primarily a set of patches for using GHC HEAD. And this is part of the picture but it misses that head.hackage is also quite a bit more.

It is primarily a tool for testing any active GHC branch against a subset of Hackage. The fact that we use patches or a Hackage overlay is merely an implementation detail (!).

Head.hackage should also be useful for non-GHC users too, eg, boot/core library authors testing if their changes break the world.

I think Rust's crater does a good job communicating this so we can take some inspiration from it (https://gitlab.haskell.org/ghc/head.hackage/-/issues/112)

Partly I would like to see the scope of head.hackage grow from a GHC developer only tool to one that any intermediate Haskell user is confident using to test ecosystem changes (a la clc-stackage) and to help them use GHC versions that do not yet have wide ecosystem support.