these 3 derivations will be built:
  /nix/store/k7qgvwc7ndhz2iynzzasnbr8w0ia4y0h-openchamber-src-with-lock.drv
  /nix/store/q49iiy6lv8nl4a2g8wvawkzmf75n7xs7-openchamber-2.7.1.drv
  /nix/store/3clj0b0xf1167qiva9zcwsy84mpvhakg-check-openchamber.drv