this derivation will be built:
  /nix/store/z51i1ycv35dwskjxdnjysc8fxbzjy2jq-inputDerivation-effect-docs-pages.drv
building '/nix/store/z51i1ycv35dwskjxdnjysc8fxbzjy2jq-inputDerivation-effect-docs-pages.drv'...