What it is

A hopper pours grey parts. A bin wants red ones. Between them is empty space, and a part only moves on a part: lay a chute and it falls. Tap a painter into the line and the parts leave it red. A ramp turns the stream, a splitter deals left, right, left, right, a mould reshapes, a filter sorts, a merger stacks one part on another. Nothing is dragged or wired: the machine is what you tapped, and the parts pour through it while you watch.

Then a hopper pours faster than one painter can paint, and you can see the queue stacking up. The fix is the best move in the game: a second line.

Screenshots

96 levels in eight wings, each wing one new idea: mixing paint, wear, lifts and pipes, grime, pistons and fans, a robot arm
A Daily Shift with a new order every day, and a streak
A crew of eight who talk back
Finite hoppers: a spill loses a part, a jam costs nothing
Three stars and a score per level; fewer lost runs is more points
No timers, no lives: build first, then press Start