Stream: beginners

Topic: roc nix flake

view this post on Zulip Drewry Pope (Nov 02 2025 at 21:04):

hi roc friends, i looked at the couple previous nix flake topics but i think this is newer..

is there an updated flake somewhere with an in-support rust version OR a zig-only version?

i'm all good with nightly builds, closer to master the better, preferably with a flake to depend on. is this possible right now? should i make some sort of hashed binary derivation instead?

view this post on Zulip Drewry Pope (Nov 02 2025 at 21:06):

(1.77.2 is eol i think, by default i try to run just a single nixpkgs when possible. i could go ahead and use the roc flake as-is without following my nixpkgs from 2025, but wanted to check first. maybe it's better if i don't rely on this flake for now, add my own derivation directly in my repo?)

view this post on Zulip Anton (Nov 04 2025 at 09:29):

Hi @Drewry Pope,

is there an updated flake somewhere with an in-support rust version

No, I have not updated the rust version so I can focus on getting the new compiler ready.

OR a zig-only version?

Yes: https://github.com/roc-lang/roc/blob/main/src/flake.nix. But, it is not ready to replace the old compiler yet.

view this post on Zulip Anton (Nov 04 2025 at 09:29):

i could go ahead and use the roc flake as-is without following my nixpkgs from 2025

That would be the approach I recommend.

view this post on Zulip Hannes (Nov 05 2025 at 01:41):

I noticed that the flake for the new Zig compiler doesn't define any output packages, is there a technical reason for that or is it just a lower priority thing?

view this post on Zulip Anton (Nov 05 2025 at 08:36):

Yeah, lower priority

view this post on Zulip Hannes (Nov 05 2025 at 09:12):

Cool, because that means I can open a PR for my local branch where I've added it :sweat_smile:

view this post on Zulip Hannes (Nov 05 2025 at 10:27):

It's open here: https://github.com/roc-lang/roc/pull/8351

view this post on Zulip Anton (Nov 05 2025 at 11:57):

Thanks, I'll check it out :)

view this post on Zulip Anton (Nov 05 2025 at 12:17):

Hmm, this is going very slowly for me:

❯ nix run ./src/#roc
warning: Git tree '/Users/username/gitrepos/forks/hasnep/roc' is dirty
[1/0/1 built] building roc (buildPhase): install -C .zig-cache/o/63519b81310eced5835dbe3ca5ae69cd/roc /nix/var/nix/builds/nix-9378-2989836767/5lsb292nlfn65p09g6aqlfz2bdbsq44h-source/zig-out/bin/roc

But when I look in activity monitor it's not using much CPU or memory at all

Last updated: Nov 09 2025 at 12:14 UTC