this derivation will be built:
  /nix/store/z6n4xp4hwmcjy9j91sid6gy59zv6fwp1-iets-fmt-0.1.0.drv
error: Cannot build '/nix/store/z6n4xp4hwmcjy9j91sid6gy59zv6fwp1-iets-fmt-0.1.0.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/rwwsa82q3a51bl9fabsfsx1bwpxlgn1d-iets-fmt-0.1.0
       Last 20 log lines:
       > cargoVendorDir not set, will not automatically configure vendored sources
       > cargoArtifacts not set, will not reuse any cargo artifacts
       > Running phase: unpackPhase
       > unpacking source archive /nix/store/1il3jc948kcczbbxx6qjfiflpx74s4wl-source
       > source root is source
       > Running phase: patchPhase
       > Executing configureCargoCommonVars
       > Running phase: updateAutotoolsGnuConfigScriptsPhase
       > Running phase: configurePhase
       > default configurePhase, nothing to do
       > Running phase: buildPhase
       > +++ command cargo --version
       > cargo 1.98.0 (797e8a9bc 2026-08-05)
       > +++ command cargo fmt -- --check
       > Diff in /build/source/tests/cli.rs:279:
       >      let _ = fs::remove_dir_all(&d);
       >      assert!(log.contains("eval: 2 derivations"), "{log}");
       >  }
       > -
       > 
       For full logs, run:
         nix log /nix/store/z6n4xp4hwmcjy9j91sid6gy59zv6fwp1-iets-fmt-0.1.0.drv