!RbXGJhHMsnQcNIDFWN:nixos.org

Haskell in Nixpkgs/NixOS

754 Members
For discussions and questions about Haskell with Nix, cabal2nix and haskellPackages in nixpkgs | Current Docs: https://haskell4nix.readthedocs.io/150 Servers

You have reached the beginning of time (for this room).


SenderMessageTime
18 Mar 2026
@alexfmpe:matrix.orgalexfmpeI'd expect haskellPackages.foo to always have the same host platform05:53:46
@alexfmpe:matrix.orgalexfmpe* I'd expect pkgsCross.foo.haskellPackages.bar to always have 'foo' as same host platform for all 'bar'05:54:28
@alexfmpe:matrix.orgalexfmpeBut bar=ghc acts special05:54:53
@alexfmpe:matrix.orgalexfmpe
In reply to @alexfmpe:matrix.org
haskellPackages in particular is 'wrong' in that it generates one derivation per package, not per component
Or rather, cabal2nix is wrong, and haskellPackages is based on throwing cabal2nix at hackage
05:55:40
@alex:tunstall.xyzAlex I believe this is due to how ghc is threaded through haskellPackages. So that mkDerivation can find it, it is bound to ghc, but this only works well for native.
It also has weird consequences when you try using other compilers, where you can e.g. end up with haskellPackages.ghc being MicroHs.
06:08:19
@woobilicious:matrix.orgwoobiliciousAhh thanks for the feedback, I don't think manual intervention is practical here, the more I think about it, the more it might be easier to just build dirivation per package, with no "real" dependencies, and then de-duplicate strings some way to prevent infinite loops.07:45:37
@co0o0okies:matrix.orgcookies joined the room.11:01:33
@me:linj.techlinjJust found a new nix interpreter implemented from scratch in Haskell https://github.com/Novavero-AI/nova-nix. Any comments?11:05:00
@b:chreekat.netchreekatBig if true11:20:30
@alexfmpe:matrix.orgalexfmpeAuthor has been announcing it in couple rooms11:29:16
@alexfmpe:matrix.orgalexfmpeSeems like AI slop11:29:25
@alexfmpe:matrix.orgalexfmpe> Hand-rolled recursive descent parser for the full Nix expression language. 13 precedence levels, 18 AST constructors,11:29:30
@alexfmpe:matrix.orgalexfmpe"Now with 30% more precedence levels. Buy 3, take 4"11:30:37

Show newer messages


Back to Room ListRoom Version: 6