| 22 Oct 2025 |
 Niclas Overby Ⓝ | Are there any good resources for getting CUDA projects, built with CUDA packages from Nixpkgs, running with libcuda.so provided by a non-NixOS host?
Can it be done with LD_LIBRARY_PATH or LD_PRELOAD? | 08:08:09 |
 hacker1024 | nixGL has worked for me in the past | 08:56:54 |
| hacker1024 | Technically that finds a kernel-compatible libcuda.so in Nixpkgs | 08:57:24 |
 Robbie Buxton | In reply to @niclas:overby.me
Are there any good resources for getting CUDA projects, built with CUDA packages from Nixpkgs, running with libcuda.so provided by a non-NixOS host?
Can it be done with LD_LIBRARY_PATH or LD_PRELOAD? If you create a /run/opengl-driver/lib (it might be called something slightly different) folder and symlink all the cuda kernel mode drivers in there. It should work out of the box | 14:40:53 |
| Robbie Buxton | * If you create a /run/opengl-driver/lib (it might be called something slightly different) folder and symlink all the cuda kernel mode drivers into there. It should work out of the box | 14:41:06 |
| Robbie Buxton | You need to add this folder to the rpaths of those drivers too others they can’t find each other | 14:41:38 |
| Robbie Buxton | I.e libcuda.so tries to load something else with nix linker | 14:42:05 |
| Robbie Buxton | * I.e libcuda.so tries to load something else with the nix linker | 14:45:15 |
 connor (burnt/out) (UTC-8) | Both nixGL and nixglhost should work I’ve also had success doing what Robbie outlined
I’ve also been able to export LD_LIBRARY_PATH and that’s worked as well | 15:02:28 |
| Robbie Buxton | * You need to add this folder to the rpaths of those drivers too otherwise they can’t find each other | 15:13:26 |
| 23 Oct 2025 |
| connor (burnt/out) (UTC-8) | Got the majority of redists in https://github.com/nixos-cuda/cuda-legacy/pull/1; still need to verify stuff builds and add more redists to the older package sets
Everything being as-is is nice, I don’t have to care nsight_systems uses an old version of Qt with known vulnerabilities | 01:28:19 |
| hacker1024 | If anyone happens to be using datacenter drivers, be aware the the GSP firmware is not loading. This might lead to unexpected performance problems.
https://github.com/NixOS/nixpkgs/issues/454772 | 04:58:50 |
|  prince213 joined the room. | 13:13:15 |
| 24 Oct 2025 |
 Daniel Fahey | Anyone with a phat rig (16+ cores 100+ GB RAM) able to test building this fix? https://github.com/NixOS/nixpkgs/pull/455364 | 20:57:01 |
 Gaétan Lepage | Yes | 22:26:21 |
| Gaétan Lepage | python313Packages.vllm built successfully with cudaSupport! | 23:13:09 |
| Gaétan Lepage | I started an extensive nixpkgs-review with cudaSupport = true but it will take a while to complete. | 23:15:33 |
| 25 Oct 2025 |
|  @washort:greyface.org left the room. | 02:21:45 |
| Daniel Fahey | Thanks! I think it's ready to merge then, I've marked the PR ready to review | 12:43:44 |
| Gaétan Lepage | I was away from my computer, but I managed to run nixpkgs-review successfully. Good job Daniel Fahey!
I've seen that happysalade merged the PR. | 18:17:00 |
| Daniel Fahey | No problem, thanks for running nixpkgs-review and good to know TorchRL and KServe are OK | 18:24:42 |
| Daniel Fahey | btw I'm having a quick look into https://hydra.nixos-cuda.org/build/1784 | 18:29:42 |
| Gaétan Lepage | Oh good! | 18:48:06 |
 asa | is there a reason packages like tensorrt require a manual installation and then running nix-store --add-fixed sha256 TensorRT-10.9.0.34.Linux.x86_64-gnu.cuda-12.8.tar.gz to put them in the nix store? | 21:41:07 |
