these 3 derivations will be built:
  /nix/store/7saf2srwhr7lr7xlvl8jq6lksm688xdr-source.drv
  /nix/store/c5sxd30cqrdhpdn891wp3ivdgmh41mnj-collie-1.19.0.drv
  /nix/store/jq0fn827g9k05qsysdbw0vg86rpy574x-check-collie.drv
warning: SQLite database '/nix/var/nix/db/db.sqlite' is busy