these 2 derivations will be built:
  /nix/store/p4vad3hhxkb8aqmgw3mk5vbvkizx1n9d-flake-inputs.drv
  /nix/store/5gldvn0g8ivp01jryjgvgsyb5ck3prk8-check-flake-inputs.drv