nix-first build plans for ghc-9.4.2 and beyond...

Horizon provides package sets targetting advance builds of GHC.

Get started with the plans:

Haskell Template:

mkdir template
cd template
nix flake init -t 'git+'

Plutus Template:

mkdir plutus-template
cd plutus-template
nix flake init -t 'git+'


Who is this for?

Haskell projects that require package sets using newly released or advanced builds of GHC.

Is there a cache?

Caching will be available in the future.

Does this use nixpkgs?

These plans can be used as an overlay on mainline nixpkgs.

Does this use haskell.nix?

No. These plans are nix-native and do not rely either on stackage or cabal's constraint solver.

Can I request advance GHC support for my package?

Yes! Please get in touch at

Will there be lts versions?

Please get in touch at