| 4 Dec 2025 |
 SomeoneSerge (back on matrix) |
problems rfc
Tha release was cut off, IMO we should push a half-assed partial impl as per my closed PR in, bc 99% of the features we don't care about
| 19:52:52 |
| SomeoneSerge (back on matrix) |
stdenv attributes
...also nuke the other 90% attributes that don't actually belong and aren't even used
| 19:53:40 |
 corroding556 | Thank you so much! cuda-legacy was exactly what I needed.
Managed to get the configuration successfully built and deployed, going to try out an application which uses CUDA soon to verify everything is in working order.
Unenviable does seem like an appropriate word, digging into all this really made me appreciate how much work goes into making any of this possible.
Pointing folks like myself on older/unsupported hardware towards cuda-legacy (an example in the wiki/manual would be great) seems like a reasonable way to do things. | 23:52:06 |
| 5 Dec 2025 |
 connor (burnt/out) (UTC-8) | Changes I've been working on:
- https://github.com/NixOS/nixpkgs/pull/467975
- https://github.com/NixOS/nixpkgs/pull/467976 (both nvcc.profile and reintroducing multiple outputs for nvcc)
| 02:05:17 |
 Kevin Mittman (UTC-7) | So CUDA 13.1 released today
https://developer.download.nvidia.com/compute/cuda/redist/redistrib_13.1.0.json | 03:34:00 |
| Kevin Mittman (UTC-7) | Now includes a binary archive tarball for cuda_compat (not for Jetson Orin) "forward compatibility" | 03:36:07 |
 Gaétan Lepage | Hi connor (burnt/out) (UTC-8)
What are you thoughts on https://github.com/NixOS/nixpkgs/pull/465751?
Not ideal as it does not solve the import issue for reverse dependencies, but at least it would allow me to move on with the vllm update. | 21:42:43 |
| 6 Dec 2025 |
| connor (burnt/out) (UTC-8) | I think it’s fine | 15:38:45 |
| Gaétan Lepage | Thanks. Can you approve the PR please? I want to avoid "self-merging" it. | 22:57:54 |
| 7 Dec 2025 |
| Gaétan Lepage | Thanks connor (burnt/out) (UTC-8)!
Actually, I was wondering whether the stubs could fix the import at build time... | 11:11:53 |
| Gaétan Lepage | Indeed (I'm quite dumb for not having made the link sooner) this issue is caused by https://github.com/NixOS/nixpkgs/pull/459416/commits/9d38d180dba19909a6058a4e16ffa1803536c4d8.
Is there a way I could disable this for this package? | 11:50:49 |
| Gaétan Lepage | Opened https://github.com/NixOS/nixpkgs/pull/468659. I think it's way better than my previous solution. | 14:24:33 |
| connor (burnt/out) (UTC-8) | Left a comment | 17:11:27 |
| Gaétan Lepage | Thanks a lot. Working on a better solution. | 17:26:06 |
| 8 Dec 2025 |
 adrian-gierakowski | is it expected for cudaSupport=true to cause nix itself to be rebuilt? https://github.com/NixOS/nixpkgs/issues/468947 | 11:22:53 |
| adrian-gierakowski | looks like so tests related deps causing this | 11:23:29 |
| adrian-gierakowski | * looks like so tests related deps causing this:
> nix why-depends /nix/store/rf0rkc1p07vgrc25b6br3f35aipipp3g-nix-2.32.4 /nix/store/awc75hb0iz3gnb4qbg3z1g9lk8jqiibi-hwloc-2.12.2-lib
/nix/store/rf0rkc1p07vgrc25b6br3f35aipipp3g-nix-2.32.4
└───/nix/store/i7chz8mn48rgmm1y8a6yy6gk6bs2dv8m-nix-2.32.4
└───/nix/store/3pvks90shqql6bvb67cc88n21r7b3sx0-nix-util-2.32.4
└───/nix/store/iq2bbr1l3ka2yfjc93gswsp43xr9a6mr-libblake3-1.8.2
└───/nix/store/bk2q02fwz5mxa4xvblcl1p89ygllm04f-onetbb-2022.3.0
└───/nix/store/awc75hb0iz3gnb4qbg3z1g9lk8jqiibi-hwloc-2.12.2-lib
| 11:26:18 |
| adrian-gierakowski | Maybe I shouldn't set cudaSupport = true systemwide, but create a separate instance of pkgs for just those package which need cudaSupport? | 12:51:02 |
 Albert Larsan | It used to rebuild at least as far back as 25.05, and still rebuilds on 25.11.
Some NixOS options change defaults based on the cudaSupport/rocmSupport values. | 12:59:11 |
| adrian-gierakowski | Thanks @albertlarsan68:albertlarsan.fr! So would you still recommend setting cudaSupport at system level? | 14:29:37 |
| Albert Larsan | That is what I do for the machines that have an Nvidia GPU, for which I eat the cost of building nix (although I have a private binary cache to which I push the closures of the updated machines before uploading the flake update to the machines) | 14:36:59 |
| 9 Dec 2025 |
| connor (burnt/out) (UTC-8) | Gaétan Lepage: SomeoneSerge (back on matrix): could one of you approve/merge https://github.com/NixOS/nixpkgs/pull/467975? | 00:09:23 |
| SomeoneSerge (back on matrix) | Robbie Buxton: have you seen https://linus.schreibt.jetzt/posts/ubuntu-images.html? Also stumbled on https://github.com/numtide/nix-vm-test while trying to remember the url | 16:35:16 |
| SomeoneSerge (back on matrix) | Nix in this case is just a tool we already had for memoization and isolation, it just happens to come with a particularly shitty scheduler | 16:36:28 |
 Robbie Buxton | No I haven’t, I’ll take a look, cheers! | 16:37:26 |
| SomeoneSerge (back on matrix) | Any other memoization solution one could build must necessarily be a version of Nix (on top of the actual Nix), likely stripped down and using heuristics instead of trying to faithfully compute the hash "of that and only that which matters"... | 16:38:47 |
| SomeoneSerge (back on matrix) | Which with the current state of affairs is probably cheaper and more efficient 🤷 | 16:39:14 |
| SomeoneSerge (back on matrix) | But mathematically still the same thing | 16:39:27 |
 tomberek | Anyone using impure derivations to explicitly have non-caching behavior? | 16:42:29 |
| SomeoneSerge (back on matrix) | No, that's not really useful? | 17:07:37 |
