these 5 derivations will be built:
  /nix/store/r81hmp0a0gg3rb1c3ckwfps2s5qms6w3-source.drv
  /nix/store/w68xykl72vc5xrlw7yk6l98pc7bdzc0h-lean-ctx-3.12.1-vendor-staging.drv
  /nix/store/d686p64982rbmsq6x6pciyvhxxv3zhks-lean-ctx-3.12.1-vendor.drv
  /nix/store/lvgydmll2y3m9xmnh1dg95fd6kqdk7qa-lean-ctx-3.12.1.drv
  /nix/store/jm2lqrzyh8sx95wsidz6j2fz1vmgzsk6-check-lean-ctx.drv