these 2 derivations will be built:
  /nix/store/0q67q6hd86rw8h145jh8ihf9gv7zpi3n-flake-fmt-1.0.0.drv
  /nix/store/b9nk4dpjxiggc9k1s23cjm3m0m5if0ac-merge-when-green-0.3.0.drv