Simple Redstone free iron farm

A compact iron farm with three villagers, a zombie in a boat and no redstone at all. When a golem spawns it steps on a pressure plate that flips a trapdoor and briefly breaks the villagers' line of sight to the zombie, so they can sleep without interrupting the spawn cooldown, then the golem walks toward the zombie and falls onto lava. It takes about ten minutes to build and can be repeated side by side. Java only.

• Java only. It runs on panic spawning with three villagers, which Bedrock does not have. Six people built the whole thing on Bedrock before finding out, despite the description saying so.
• Path block far wider than the video shows. On 26.2 about five extra blocks on every side, and check for cave openings in a 17 by 13 by 17 area centred on the villagers, or golems spawn outside the farm.
• Do not build near another village. Nearby villagers wreck the bed pathing, and any golem within 16 blocks makes these villagers behave as though one already exists.
• Bed orientation matters and the boat has to sit exactly in the middle. Getting either wrong is the usual reason nothing spawns.
• Light the surrounding area. The design uses the golem's own aggro to walk it away, so a wandering mob will distract it and stall the cycle.
• To scale it, copy the whole plot to the north, east, south or west with a one block gap between plots. Do not stack it upward.