these 2 derivations will be built:
  /nix/store/v15w22hcz55xl846jvsnc2f80vxp54x7-freebuff-linux-x64.tar.gz.drv
  /nix/store/ldq91l02vp2483vh9aggv9zmmvrd5k39-freebuff-0.0.178.drv