| 11 May 2026 |
 John Ericson | this seems not unlike the the issues that hydra.nixos.org was facing frankly | 20:03:12 |
| John Ericson | the thing I am working on right now (but it is a massive refactor) is making the builder not get dependent drvs so it that it has to subsitute or fail, and rebuilding things is not possible | 20:03:44 |
| John Ericson | that also cuts down on traffic between the queue ruunner and the builder | 20:03:54 |
| John Ericson | the current thing is how really old remote building worked | 20:04:09 |
| John Ericson | the thing I am going to is how hydra workedf or the last decade or so | 20:05:28 |
 Frooastside | I was not sure which setting is actually required because it didnt work after just enabling services.hydra-queue-builder-dev.useSubstitutes = true; (on the builder) so I also set nix.settings.builders-use-substitutes = true (I am not sure where i found that) and this is of course also set nix.settings.substituters = ["https://cache.nixos.org" "https://cache.MY CACHE"] | 20:07:01 |
| John Ericson | yeah taht sounds like it should work | 20:08:56 |
| John Ericson | it is just hard to debug right now I am afraid with the dependency drvs being disclosed to the builder | 20:09:15 |
| John Ericson | you could try to check nix logs and figure out what it is doing what it is doing | 20:09:28 |
| John Ericson | but that is hard | 20:09:31 |
| John Ericson | (the decision to build the stuff is nix's) | 20:10:28 |
| Frooastside | This is the process running right now
hydra-q+ 84985 0.0 0.2 595328 34872 ? Sl 21:17 0:00 nix --extra-experimental-features nix-command build --json --no-pretty --print-build-logs --log-format raw-with-logs --no-link --max-silent-time 7200 --timeout 36000 --option max-build-log-size 67108864 --option fallback true --option substitute false --option builders /nix/store/bx33y6dvsb44avnjah0hsh25hj0axa0f-users-groups.json.drv^*
So it picked the first drv that is not in the cache and tries to build it but --option substitute false is set
| 20:15:15 |
| Frooastside | Thats whats confusing me, how is it supposed to work? When the builder is missing dependencies, should nix get them because substitutions should be on, should the queue-builder get them from the cache or should the queue-runner send them to the builder? | 20:21:45 |
| John Ericson | interesting, I am not sure where that is coming from | 20:34:42 |
| John Ericson | oh nevermind I do see it | 20:35:24 |
| John Ericson | that is in subprojects/crates/nix-utils/src/realise.rs | 20:37:02 |
| John Ericson | git log missed it becasue it was there since the initial commit (?) | 20:37:17 |
| John Ericson | oh because I was git loging the specific file | 20:39:10 |
| John Ericson | Frooastside: the instent is that the new builder and new queue runner will cooporate to get the inputs in place separately | 20:40:09 |
| John Ericson | so nix shouldn't need to download anything | 20:40:16 |
| John Ericson | but clearly that is not working right yet | 20:40:20 |
| Frooastside | Ok, thank you | 20:41:05 |
| 12 May 2026 |
 Morgan (@numinit) | FYI https://nixos.org/hydra/manual/ seems broken due to CORS rules | 03:51:51 |
| Morgan (@numinit) | Any sense where they're coming from? Took a quick look in https://github.com/NixOS/infra/blob/main/build/hydra-proxy.nix to fix it but didn't see anything | 03:53:31 |
| Frooastside | I tried getting the old queue-runner working but i face a weird issue where it just gets stuck on "sending inputs..." it tries to copy things from the s3 store but never finishes im not even sure whats the problem there. the only option is to manually kill the nix-daemon processes, systemctl restart nix-daemon doesnt touch the stuck processes. after doing that i can manually copy the nix store paths though im not sure if it works manually because its only one at a time or something else | 09:10:28 |
|  Harinn joined the room. | 18:14:22 |
 tomberek | Can the new queue-runner serve as only a coordinator/scheduler, but not perform any build/signing actions on it's own (eg: without even having a functioning Nix store locally?). Use-case: CI with ephemeral builders needing a centralized coordinator. | 20:49:03 |
 hexa | yes, it can | 20:49:24 |
| hexa | using pki for onboarding new nodes and the presigned urls feature to decentralize uploading | 20:49:59 |
| Frooastside | I think the problem might have been nix.settings.auto-optimise-store = true it seems to work now (for at least 2 minutes and it stopped every 10 seconds or so) | 22:31:22 |
