| 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 |
| 10 Dec 2025 |
| SomeoneSerge (back on matrix) | * No, that's not really useful?
Edit: we generally do want memoization (caching), as well as ability to deterministically name things in sentences "X succeeds (fails)". Just that so far we haven't included all relevant platform info in the derivation, so the equivalence classes are too big. It's one line fixable though
| 18:29:41 |
| SomeoneSerge (back on matrix) | * No, that's not really useful?
Edit: we generally do want memoization (caching), as well as ability to deterministically name things in sentences "X succeeds (fails)". Just that so far we haven't included all relevant platform info in the derivation, so the equivalence classes are too big. It's one line fixable though
Impure derivations just add sandboxing that needs to be bypassed, and a scheduler that is more of a liability
| 18:30:29 |
 Ari Lotter | hm looks like vllm fails to build because outlines has a test that imports libcuda.so on collection.. | 22:03:19 |
| SomeoneSerge (back on matrix) | https://github.com/NixOS/nixpkgs/pull/465751#issuecomment-3604113652 | 23:30:45 |
 apyh | hahaha you're already ahead of me! | 23:31:20 |
| SomeoneSerge (back on matrix) | Gaetan has been on it | 23:32:00 |
| apyh | yeah, seems like there's a clear path to patch / upstream a fix to llama cpp python to make it lazy | 23:33:22 |
| apyh | btw i posted logs about that torch nvrtc thing | 23:33:36 |
| 4 Aug 2022 |
|  Winter (she/her) joined the room. | 03:26:42 |
| Winter (she/her) | (hi, just came here to read + respond to this.) | 03:28:52 |
 tpw_rules | hey. i had previously sympathzied with samuela and like i said before had some of the same frustrations. i just edited my github comment to add "[CUDA] packages are universally complicated, fragile to package, and critical to daily operations. Nix being able to manage them is unbelievably helpful to those of us who work with them regularly, even if support is downgraded to only having an expectation of function on stable branches." | 03:29:14 |
| Winter (she/her) | In reply to @tpw_rules:matrix.org
i'm mildly peeved about a recent merging of something i maintain where i'm pretty sure the merger does not own the expensive hardware required to properly test the package. i don't think it broke anything but i was given precisely 45 minutes to see the notification before somebody merged it ugh, 45 minutes? that's... not great. not to air dirty laundry but did you do what samuela did in the wandb PR and at least say that that wasn't a great thing to do? (not sure how else to word that, you get what i mean) | 03:30:23 |
| tpw_rules | no, i haven't yet, but i probably will | 03:31:03 |
| Winter (she/her) | i admittedly did that with a PR once, i forget how long the maintainer was requested for but i merged it because multiple people reported it fixed the issue. the maintainer said "hey, don't do that" after and now i do think twice before merging. so it could help, is what i'm saying. | 03:31:50 |
| tpw_rules | i'm not sure what went wrong with the wandb PR anyway, i think it was just a boneheaded move on the maintainer's part | 03:32:10 |
| Winter (she/her) | (it was also simple enough that it was fine and the maintainer said it looked good after) | 03:32:15 |
| tpw_rules | * i'm not sure what went wrong with the wandb PR anyway, i think it was just a boneheaded move on the merger's part | 03:32:19 |
| tpw_rules | but i thought most of the frustration was around packages which don't really involve CUDA breaking the fragile CUDA packages, and i'm not sure how the warning helps in this case. it's not like nixpkgs-review prints out the comments. maybe i'm wrong. but it is a legitimate problem | 03:34:19 |
| Winter (she/her) | the frustration that i see is that people are touching packages that he maintains, am i missing further context here? | 03:35:09 |
| tpw_rules | did you ever see this? https://discourse.nixos.org/t/nixpkgss-current-development-workflow-is-not-sustainable/18741 | 03:35:43 |
| Winter (she/her) | oh yes i did | 03:35:49 |
