this derivation will be built:
  /nix/store/fr2cpgkpbx4hq915m6vj2005plz4w1g0-inputDerivation-effect-docs-pages.drv
building '/nix/store/fr2cpgkpbx4hq915m6vj2005plz4w1g0-inputDerivation-effect-docs-pages.drv'...