these 2 derivations will be built:
  /nix/store/pvqc3qbsd2nmrvc55sc780k1l6kq4ahw-flake-fmt-1.0.0.drv
  /nix/store/kh1145nsrnnna5gkk96nxkhi8yac8lkg-merge-when-green-0.3.0.drv