Nixos stable 25.11

[benalleng]

Also supercedes #1022 as there were a lot of changes I would need to duplicate here to do proper flake checks

I was having a hard time getting cargo-llvm-cov to compile and pass tests so I skipped the tests in 49c82d7

passed nix flake check

Pull Request Checklist

Please confirm the following before requesting review:

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  AI
  in the body of this PR.
• I have read CONTRIBUTING.md and rebased my branch to produce hygienic commits.

[coveralls]

Pull Request Test Coverage Report for Build 20034221122

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 83.462%

---

Totals
Change from base Build 19938128275:	0.0%
Covered Lines:	8998
Relevant Lines:	10781

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💛 - Coveralls

[nothingmuch]

utACK, but i would appreciate one comment on the line i don't understand and someone else should also review since i had a hand in some of the changes here

[arminsabouri]

someone else also review since i had a hand in some of the changes here

cc @thebrandonlucas

[thebrandonlucas]

Cool, I can give this a review tomorrow

[benalleng]

I found that we can actually get rid of this build check ignore here NixOS/nixpkgs#468002 going to label this as blocked until that is merged in.

[benalleng]

The update to nixos-25.11 has had the cargo-llvm-cov update backported in so we now no longer need the workaround, see the build success in nixos-25.11 release https://hydra.nixos.org/build/315952046

[nothingmuch]

ACK, tested on linux