these 2 derivations will be built:
  /nix/store/4n9jsxvbar7vbqsw08r4q3nzrjknkln2-iets-0.1.0.drv
  /nix/store/bkwwc2bh7lvsrq6w2lxbzfg2cjzbxjab-iets-diff-e2e.drv