| 9 Jan 2026 |
 sterni | ners: it would already be helpful if you could open an issue for the problem and obtain the contents of config.log (written by autoconf). You can get that by building witih --keep-failed. | 15:31:18 |
| sterni | also link this piece of information, please: https://github.com/NixOS/nixpkgs/pull/466258#issuecomment-3651073416 | 15:32:43 |
 Artem | i'm trying to build simple liquidhaskell app (https://github.com/ulysses4ever/liquid-haskell-demo) with
# default.nix
(pkgs.haskellPackages.callCabal2nix "liquid-haskell-app" ./liquid-haskell-app {}).overrideAttrs (old: {
nativeBuildInputs = (old.nativeBuildInputs or []) ++ [ pkgs.z3 ];
})
when I run nix-build I see that the builder runs haddock, which conflicts with liquid haskell (). I tried adding doHaddock = false; in the overrideAttrs but that didn't change a thing. What am I missing to turn off Haddock?
| 18:35:48 |
| sterni | you need to use the override interface of the haskell builder, not overrideAttrs | 18:36:22 |
| sterni | i.e. haskell.lib.compose.overrideCabal | 18:36:28 |
 andromeda | In reply to @sternenseemann:systemli.org
ners: it would already be helpful if you could open an issue for the problem and obtain the contents of config.log (written by autoconf). You can get that by building witih --keep-failed. most helpful thing I learned today: --keep-failed exists | 19:02:01 |
| Artem | sterni: i tried
pkgs.haskell.lib.overrideCabal (pkgs.haskellPackages.callCabal2nix "liquid-haskell-app" ./liquid-haskell-app {}) (old: {
nativeBuildInputs = (old.nativeBuildInputs or []) ++ [ pkgs.z3 ];
doHaddock = false;
})
but that fails with a type error:
error: function 'anonymous lambda' called with unexpected argument 'nativeBuildInputs'
| 19:06:06 |
| sterni | That’s expected the dependency declarations are named different there to match cabal | 19:06:47 |
| sterni | you can look it up in the nixpkgs manual under “specifying dependencies” in the haskell section | 19:07:13 |
| Artem | great, "buildTools" worked. Thanks a lot! | 19:16:47 |
| andromeda | liquid haskell looks really cool | 19:48:59 |
| Artem | apparently, core liquid packages in nixpkgs are built without liquid annotations for the same reason: Haddock was enabled by default. So, now I need to disable it there. haskell-modules/configuration-nix.nix seems like the right place? And it should look fairly similar (oveerideCabal) I guess. | 20:46:49 |
| 10 Jan 2026 |
|  pnotequalnp joined the room. | 05:15:41 |
|  Jean 💕 joined the room. | 11:28:04 |
 tks_123 | mates | 13:02:04 |
| tks_123 | Is there a way to add a haskell package as a flake (i.e. some other haskell project with its own flake.nix) into the haskellPackages of my own haskell project? | 13:03:37 |
| tks_123 | are there examples of this out there? | 13:03:45 |
 Acid Bong | In reply to @tks_123:matrix.org
Is there a way to add a haskell package as a flake (i.e. some other haskell project with its own flake.nix) into the haskellPackages of my own haskell project? yup, but i hope they expose a package.nix with the package recipe alone, so you could haskellPackages.callPackage it | 13:25:26 |
| Acid Bong | (for the sake of using the same version and edition of GHC) | 13:26:01 |
 maralorn | Its complicated, the default flake interface is not really meant to be composable. | 16:03:30 |
| maralorn | Some flake authors design their flake in a way that they expose a) the package and b) an overlay which injects the package. | 16:04:05 |
|  aiya joined the room. | 19:38:17 |
| aiya | so the 25.11 "default" GHC is 9.10, but LLVM only has 18-20 which is incompatible. is this intentional, or is LLVM 15 supposed to be in nixpkgs just to support 9.10 -fllvm?
i back-searched this chat for LLVM but only found conversation on bumping LLVM 12 -> 15 | 19:50:59 |
 emily | we backport patches for newer LLVM support to older GHCs | 19:52:34 |
| emily | (there aren't that many, the backend doesn't change much since it uses the LLVM textual IR format) | 19:52:52 |
| emily | (mostly it's just backporting bumps to the version number it checks) | 19:53:02 |
| emily | see pkgs/development/compilers/ghc/common-llvm-patches.nix | 19:53:14 |
| 11 Jan 2026 |
|  ivan joined the room. | 01:54:59 |
 iqubic (she/her) | What should I do if Nix is refusing to build a Haskell Library for me? Right now, hip is failing to build! https://hackage.haskell.org/package/hip | 03:30:09 |
| iqubic (she/her) | error: Package ‘hip-1.5.6.0’ in /nix/store/aqhcr0kv7d91rfm0ca77rbakjk5gkbq6-source/pkgs/development/haskell-modules/hackage-packages.nix:330406 is marked as broken, refusing to evaluate.
a) To temporarily allow broken packages, you can use an environment variable
for a single invocation of the nix tools.
$ export NIXPKGS_ALLOW_BROKEN=1
Note: When using `nix shell`, `nix build`, `nix develop`, etc with a flake,
then pass `--impure` in order to allow use of environment variables.
b) For `nixos-rebuild` you can set
{ nixpkgs.config.allowBroken = true; }
in configuration.nix to override this.
c) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add
{ allowBroken = true; }
to ~/.config/nixpkgs/config.nix.
note: trace involved the following derivations:
derivation 'mh26'
| 03:36:54 |
