this derivation will be built:
  /nix/store/f04yasfzx6zb23c7gncz2f5wx7mn29wc-merge-when-green-0.3.0.drv
this path will be fetched (13.0 MiB download, 37.5 MiB unpacked):
  /nix/store/y88vb9jjsys36w8x4bfhia721fpzmyg8-gh-2.99.0