these 2 derivations will be built:
  /nix/store/16d88vff6dc69dqy5ki5mqmv61jswxd6-source.drv
  /nix/store/jlaz7gwg83cw0rnrvdh2k1h3v8f6jjc5-nix-shell.drv
error: hash mismatch in fixed-output derivation '/nix/store/4z2cv1y6nf4jbh3hn4ppvv6m0i314sbf-source.drv':
         specified: sha256-fcGVoV0Vd8TrYDE730W9GBHcVjTXB3oGqWzJRErBBzk=
            got:    sha256-uWORGGTafVZaTQV6a9ryETtYba0XKRpgti/WPJpIM6Q=
error: build of resolved derivation '/nix/store/4z2cv1y6nf4jbh3hn4ppvv6m0i314sbf-source.drv' failed
error: Cannot build '/nix/store/jlaz7gwg83cw0rnrvdh2k1h3v8f6jjc5-nix-shell.drv'.
       Reason: 1 dependency failed.
       Output paths:
         /nix/store/5z4qai0bnc28j59aa41m18z7wfa8njbh-nix-shell