these 2 derivations will be built:
  /nix/store/1n3a2cpczilrjpfzsgh2xg9sdg2lxx5d-source.drv
  /nix/store/q9ayq0a9krg7sbmbqyz2krpri5zmls60-collie-0.36.1.drv
warning: SQLite database '/nix/var/nix/db/db.sqlite' is busy