this derivation will be built:
  /nix/store/x6cl52j36jjndg0d4k5jf307xsd4jk2a-nix-shell.drv
building '/nix/store/x6cl52j36jjndg0d4k5jf307xsd4jk2a-nix-shell.drv'...
Running phase: buildPhase
warning: you did not specify '--add-root'; the result might be removed by the garbage collector