Outputs existing in local store but not in cache are not built

[baracoder]

I want to use nix-build-uncached on persistent builders, so that builds are even faster, because dependencies are already cached.

I have this script to build new outputs and upload them

      nix-build-uncached ./ci.nix -build-flags '-o results/x'
      if [ -e results/x ]; then
        nix -v sign-paths -r --key-file $NIX_CACHE_KEY ./results/x*
        nix copy --to $BINARY_CACHE_URL ./results/x*
      fi

Now if I mess up the signing & uploading part, I end up in a situation, where the outputs are present on the builder but not in the cache and nix-build-uncached will not create any outputs.

Unfortunately nix-build --dry-run does not provide any information about those paths.

Related NixOS/nix#1607

[Mic92]

I have this problem too, but not yet a solution.