| 1 Jul 2025 |
 djacu | Hey Cuda Team
In case you haven't seen the recent post on discourse, the Marketing Team is preparing this year's community survey. I am reaching out to teams to see if there are any questions they would like to add to the survey to better serve the work you all do. More details in the post linked below.
https://discourse.nixos.org/t/community-feedback-requested-2025-nix-community-survey-planning/66155 | 03:24:48 |
| 2 Jul 2025 |
|  apyh joined the room. | 17:28:38 |
| 3 Jul 2025 |
 connor (he/him) | SomeoneSerge (Ever OOMed by Element): it occurred to me, this PR I'm going to be reviewing (https://github.com/NixOS/nixpkgs/pull/420575) could potentially serve as a way to inject information about requiredSystemFeatures into the contents of a derivation. It would be possible to have the GPU hook look for that content within the derivation and allow remote builders with GPUs to work as expected, right? (My recollection was that because the requiredSystemFeatures stuff wasn't in the derivation that even if a build was routed to a GPU-equipped builder it wouldn't know to add the GPU to the sandbox because the derivation content gave no indication that it should.) | 15:28:22 |
| 5 Jul 2025 |
 aidalgol | Would ZLUDA be under the purview of the nixpkgs CUDA maintainers? | 05:54:53 |
| 7 Jul 2025 |
|  @tobtobxx:matrix.org left the room. | 14:27:56 |
| 8 Jul 2025 |
| connor (he/him) | In reply to @aidalgol:matrix.org
Would ZLUDA be under the purview of the nixpkgs CUDA maintainers? I don’t think it would be since it’s expressly about getting CUDA stuff working on non-NVIDIA devices (although that would definitely benefit from functioning packages!)
AFAICT it’s also in violation of NVIDIA’s EULA for that exact reason :/ | 08:37:41 |
| connor (he/him) | SomeoneSerge (Ever OOMed by Element)two things:
- Can we push back our weekly by 30m? (I’m still not asleep so today is going to be brutal)
- I was getting ready to fix up one of the doc PR and remembered this comment: https://github.com/NixOS/nixpkgs/pull/414612#discussion_r2137625627. Do you still feel that tooling needs to exist prior to the changes to documentation along the lines of what’s proposed in the PR is merged?
| 08:41:14 |
| connor (he/him) | Okay, bonus thing: I’ve been taking a swing at getting the required-nix-mount stuff you wrote working with Jetson devices | 08:42:50 |
| connor (he/him) | Also in case people didn't see this, some exciting changes coming in the next release! https://github.com/NixOS/nix/pull/13407 | 14:59:43 |
| 10 Jul 2025 |
| connor (he/him) | If anyone has the bandwidth to look at https://github.com/NixOS/nixpkgs/pull/422208 or https://github.com/NixOS/nixpkgs/pull/419335, I'd appreciate it | 22:52:13 |
| 13 Jul 2025 |
|  @me:caem.dev left the room. | 00:13:30 |
| 15 Jul 2025 |
|  farmerd joined the room. | 03:17:28 |
| farmerd | I don't know if anyone has a minute to help double check me on something quickly but I've tried about half a dozen different ways to get pytorch working on nixos with cuda and I am continually getting build errors. This flake (https://github.com/mschoder/nix-cuda-template ) seemed like something that perhaps someone else could quickly check to see if the compilation issues I'm seeing are just me or more widespread? For me it actually generates a segfault in GCC so it's quite bizarre. | 03:23:11 |
 mcwitt | Hi farmerd , could you say a bit more about what you're trying to do and what specific errors you see?
For basic pytorch usage with the CUDA backend, the following minimal flake seems to work fine for me (just tested on nixpkgs-unstable): https://gist.github.com/mcwitt/b6c8da58a2e1fcbc1c2728f8f60ad136
| 18:04:39 |
| farmerd | I'm just trying to get pytorch working with my gpu. But whatever I try to do it ends up trying to build the cuda toolkit and GCC has an internal segfault when trying to build NCCL. | 21:16:02 |
| farmerd | I think my current suspicion is that I've got a hardware issue though so I'm going to try addressing that tomorrow and see if I still have issues. | 21:17:17 |
| mcwitt | have you tried updating the nixpkgs pin? (nix flake update nixpkgs). That at least should let you use a cached toolkit and skip the build (unless you're also overriding for some reason) | 21:19:16 |
| mcwitt | if your goal is just to get a python env running with pytorch and CUDA, I'd recommend starting with a more minimal flake (like the one I posted above) | 21:20:42 |
