these 3 derivations will be built:
  /nix/store/il4nhncwl15gx3fvzqhs29lhj411ymyp-source.drv
  /nix/store/9lz1hy0sznzsqz4qczn8xh7cr06xibqz-fx-0.0.11.drv
  /nix/store/r756ixbircj4cmfamzhlk6imsyjgka9b-check-fx.drv
warning: SQLite database '/nix/var/nix/db/db.sqlite' is busy