Haskell.nix contains several Nixpkgs pins imanaged by
These are used in testing various versions of nixpkgs.
To use haskell.nix the
overlays need to be applied to
Nixpkgs. Users should probably pin a suitable version of nixpkgs, although things might not work for them if their Nixpkgs version is
We aim to keep this pin somewhere on a channel of the Nixpkgs latest stable release. That is currently 20.09.
We also execute tests on MacOS (darwin). The darwin channel is usually
behind the NixOS channel. So we follow the