6 Jul 2025 |
Alex | In reply to @alexfmpe:matrix.org might need withHoogle = true, don't remember if default in shellFor Not default, unless it has changed recently. | 00:10:58 |
alexfmpe | indeed | 00:12:02 |
alexfmpe | https://github.com/NixOS/nixpkgs/blob/a697a033bd07502703b151797085e5c7b64c6f31/pkgs/development/haskell-modules/make-package-set.nix#L453 | 00:12:03 |
Alex | In reply to @collinarnett:matrix.org Does the hoogle server serve the haddocs as well? I'm not really sure what I'm looking for so I would like to browse the docs like I would on hackage. Note that how Hoogle serves Haddocks is affected by the --local flag.
(For most users, running with --local works better.)
See https://github.com/ndmitchell/hoogle/blob/e83646ee1b62eb724def6c838a34017b60fc519a/docs/Install.md#server | 00:14:08 |
woobilicious | Is there anyway to "export" a build plan for haskell apps based on the nixpkgs version? trying to think how to compile my code for windows, and cabal obvious isn't going to pull in the exact same versions without some hints. I guess I could look at cross compiling using mingw64 version of ghc in nixpkgs, but that might just be a huge headache. | 05:56:37 |
Alex | In reply to @woobilicious:matrix.org Is there anyway to "export" a build plan for haskell apps based on the nixpkgs version? trying to think how to compile my code for windows, and cabal obvious isn't going to pull in the exact same versions without some hints. I guess I could look at cross compiling using mingw64 version of ghc in nixpkgs, but that might just be a huge headache. Have you tried cabal freeze ? | 06:23:48 |
woobilicious | oh thanks, I didn't realise that existed...kinda half forgot cabal added some modern features, as I used to use stack on windows and nixpkgs now. | 06:44:58 |
8 Jul 2025 |
@dmjio:matrix.org | is there a function to parse a flake lockfile into a set?
let sources = parseFlakeLock (builtins.readFile ./flake.lock);
something like this
| 16:07:35 |
ners | Yes, in fact flake-compat is based on this principle. See examples here: https://github.com/nix-community/flake-compat | 16:13:58 |
ners | * Yes, in fact flake-compat is based on this principle. See examples here: https://github.com/nix-community/flake-compat
Basically: builtins.fromJSON (builtins.readFile ./flake.lock);
| 16:14:48 |
@dmjio:matrix.org | so I'm just doing this rn
# fetch from flake.lock
with (builtins.fromJSON (builtins.readFile ../flake.lock));
fetchFromFlakeLock = args:
fetchFromGitHub {
inherit (args.locked) owner repo rev;
hash = args.locked.narHash;
};
servant = fetchFromFlake (nodes.servant);
| 19:50:58 |
@dmjio:matrix.org | does fetchFromFlakeLock already exist somewhere | 19:51:18 |
@dmjio:matrix.org | okay will check it out, we'll see | 19:54:50 |
@dmjio:matrix.org | Also, is there a way to generate a flake.nix on the fly, similar to how callCabal2nix works | 19:55:07 |
@dmjio:matrix.org | not all my repos have flakes and I'd have to add it to each one basically | 19:55:29 |
@dmjio:matrix.org | but I'm going to just override the nixpkgs with nixpkgs.follows anyways | 19:55:39 |
@dmjio:matrix.org | otherwise the flakes will be mutually recursive | 20:02:12 |
@dmjio:matrix.org | * otherwise the flakes will be mutually recursive (some of them) | 20:02:23 |
@dmjio:matrix.org | Also | 21:19:51 |
@dmjio:matrix.org | Who is the CEO of Flakeroku | 21:19:57 |
@dmjio:matrix.org | What is the flake heroku equivalent | 21:20:15 |
sellout | I’m having a hell of a time caching this one project, I think it must be related to Haskell / IFD. I follow the Cachix instructions for caching build & runtime deps (https://docs.cachix.org/pushing#pushing-build-and-runtime-dependencies), I do that on all three supported systems, and then I expect in this CI run (https://github.com/sellout/unison/actions/runs/16144540250), that it won’t have to build anything. But that’s never what happens. You can see the two macOS runs are 2-3 hours, and the linux one gets “canceled” for some reason I can’t deduce (but not before trying to build a ton of stuff). It’s on this branch (https://github.com/sellout/unison/tree/update-nix), but I feel like I run into this every time I update Nix at all. When I run it on a different machine locally, I just see “evaluating derivation '…#all'” for ages before anything else happens, which is what makes me think it’s IFD. | 22:58:47 |
| @vigress9:matrix.org left the room. | 23:21:02 |
9 Jul 2025 |
| jonhermansen joined the room. | 01:18:54 |
Patrick Steele | Does anyone have an example of how to structure a flake to allow builds to run with profiling enabled? If I add -prof to my cabal file, I get Failed to load dynamic interface file for Prelude errors, even in a simple project with no dependencies. | 02:18:05 |
Patrick Steele | My flake is https://pastebin.com/hUxz89uA right now. I've tried various incantations from https://github.com/NixOS/nixpkgs/blob/master/doc/languages-frameworks/haskell.section.md to try to coerce profiling to work. | 02:20:01 |
Patrick Steele | I'm wondering whether my use of pkgs.haskellPackages , as opposed to e.g. pkgs.haskell.packages.ghc984 , is somehow an issue | 02:21:34 |
eldritchcookie | for those that use the nixpkgs haskell infrastructure on ghc 9.12.2 do you have rename capability with hls? i am trying to narrow down where the issue is and while it seems that version 2.11.0.0 has full support i was unable to find if the version 2.10.0.0 has the hls-rename-plugin | 11:35:17 |
chreekat | i've thought about this | 12:33:53 |
maralorn | I am pretty sure unison uses haskell.nix yes, that is a ton of IFD. However of course building the exact derivation twice should work. | 14:04:09 |