Missing cache for qtwebengine

For the last 2-3 weeks, whenever I did nixos-rebuild, I keep missing the cache for kdePackages.qtwebengine (if not more packages), and it’s too big of a build for my machine to handle; leading me to not be able to upgrade at all. I looked quite a bit on GH issues, etc. and no one else seems to be having this issue?

I checked out my config comparing the changes I’ve made since my last successful rebuild, and it’s just adding a line to my Kitty config, nothing that could possibly mess with the cache substituters. Moreover, I don’t have any overlays that could be causing a custom build. Here’s my config repo: GitHub - GetPsyched/homeless-shelter: my nix config

Looking at hydra, that package has been successfully built the past few weeks, so you must either be modifying it somehow (check your overlays) or you’re on a revision of Nixpkgs that hydra has not entirely built yet.

Which channel are you on? unstable-small may advance before everything is built for instance.

Is qtwebengine a channel blocker for any channel? If not, the channels may advance before it’s built.

Channel blockers mean the channel won’t advance if they don’t build but it’ll still wait for the entire rest of the eval to finish building and then advance regardless of whether those are successful or not.

unstable-small will only wait for a subset of the eval but also not advance if the blockers fail.

3 Likes

Nope, no overlays.

I’m on nixos-unstable, and even an older revision which was then tagged nixos-unstable has this same issue. So I’m pretty sure it’s not a revision that’s not cached.

Which host’s config are you trying to build?

piglin (sorry, should’ve mentioned that)

I found the issue just now. I don’t have overlays, but I have my own derivations; and indeed it was one of them (pyside6-essentials). This was building just fine the last time I did a switch. Something in nixpkgs must’ve changed for this to fail; still figuring out what that is.

EDIT: It’s specifically this line: homeless-shelter/packages/pyside6-essentials.nix at 1cfb16aa26d89173379e9cc2f76e1083e87bf8eb · GetPsyched/homeless-shelter · GitHub

EDIT 2: nix-shell -p qt6.full works (doesn’t build locally), but I noticed that it downloads qtwebengine-6.8.0, and when building the above package as part of my config, it builds qtwebengine-6.8.1

That’s because nix-shell is using the current value of <nixpkgs> from NIX_PATH, which is probably pointing at flake:nixpkgs, which is the revision of nixpkgs that was used to built your current system, while your flake is on the newer nixpkgs revision already.

Yeah, that makes sense. I did that again after rebuilding and it gets it without any cache issues (while the rebuild still misses the cache). Fuck me I guess.