this derivation will be built:
  /nix/store/ir1rx4b2k3jrq45r3wyzm8rjgzzmrxvn-inputDerivation-gh-pages.drv
building '/nix/store/ir1rx4b2k3jrq45r3wyzm8rjgzzmrxvn-inputDerivation-gh-pages.drv'...