Five layer AFK gold farm

A small gold farm on the nether roof, five magma platforms and no redstone in it. A turtle egg on each layer pulls the zombified piglins to a hole in the middle and they drop onto a hopper floor where the fall and entity cramming finish them. It makes around 600 gold ingots an hour and runs fully AFK, which also means no golden swords clogging the chests, since mobs only drop their gear when a player lands the kill. Java only, and at 2635 magma blocks it is one of the cheapest builds here.

mobGriefing has to be on, and each turtle egg needs two blocks of air above it, which means breaking the block under the egg. Every report of the piglins ignoring the eggs comes down to one of those two.
It has to sit over nether wastes. One builder had a dead farm until he rebuilt it in the right biome.
Only about half the piglins die from the fall. The armoured ones have 50 to 100 health and survive it. Replace the slab on the hoppers with mud and wither roses, or put a layer of lava by the kill chamber, which raised one builder's rate by about half. Campfires do nothing, piglins are immune to fire.
Do not add more layers. The mob cap holds you at roughly 80 piglins at a time, so extra platforms give nothing and they tilt the despawn sphere down far enough that you have to start spawnproofing under the bedrock.
Set the difficulty to hard, which is the creator's own answer to the slow rate question.
For the magma, either crouch, wear frost walker boots or drink fire resistance. That is most of the pain in this build.