Notes on My First Factorio Mod: Why I Stopped Trusting the Shift-Click Dance

If you're running 32-wagon trains with 4 chests per wagon (2 on each side), you're managing 128 chests that all have to stay perfectly in sync. I used to do the "Shift-click dance": Shift+Right Click to copy an inserter, then Shift+Left Click down the line 128 times to paste the stack size. But if you miss just one inserter in that line, the whole station is compromised. One chest fills up with too much of one item, the wagon finishes late, and the 32-wagon beast sits in the docking bay like a stuck semi-truck at an Amazon warehouse, blocking the entire intake until the throughput drops and the whole base stalls. I've seen factories get so backed up from a single mismatched inserter that it was honestly easier to nuke the whole thing and start over. I wrote this mod because I realized I couldn't trust my own hands to do the paste-dance 128 times without a mistake. The GUI switchboard mess I assumed Factorio's GUI API would have some kind of modern data binding. I was wrong. It's a manu