Prime a furnace, assembler or chest with the exact ingredients and fuel amounts its recipe needs, down to a partial stack. Chests also take exact item counts. Drag over a row, ghost or built, to prime every machine of one kind, or stamp primed blueprints. Boilers, burner drills and locomotives get just the fuel. Construction robots deliver the item request.
Providing the player with new tools or adjusting the game interface, without fundamentally changing gameplay.