Original by LemonLake (Drew Lemmy). https://bitbucket.org/Lemmmy/factory/
Forum link: https://forum.minetest.net/viewtopic.php?f=11&t=9277
Forked on github to bring it back to a working state.
Original readme.txt said:
Change this folder name from 'LemonLake-factory-xxxxxx' to 'factory' or else it won't work!