these 2 derivations will be built:
  /nix/store/nlijbzzlmfzlicxywgssklnvjkhyh2jh-gascity-1.5.1.drv
  /nix/store/nzb5h6l8f7n9rv877ag2bscav50vnyaw-check-gascity.drv
this path will be fetched (6.2 KiB download, 53.6 KiB unpacked):
  /nix/store/zqjhg1xjxhp1d1klnqpxbsrvf1zm9vjk-flock-0.4.0