Fastest shulker farm

Kayzm's 48 minute engineering breakdown of the fastest shulker farm ever built, at 600,000 shells an hour. It is a record attempt rather than a build guide, and it comes with world downloads at three scales instead of a tutorial. The catch is that Mojang changed minecart ejection in 1.20.3 and the cells stopped accepting shulkers. The creator said he was working on a redesign and never published one, so on current versions this runs well below its headline if it runs at all.

• Minecart ejection changed in 1.20.3 and shulkers no longer go into the cells. The creator confirms it in the comments and says a cell redesign was coming, but none was ever posted.
• One builder offers a fix, an activator rail where the lower curved rail sits, powered by a redstone block instead of the trapdoor. They never tested it at full scale.
• On 1.21.10 it runs but reaches only 183,000 an hour in its most efficient mode, and the builder who measured it says it is not worth building at that version.
• Both the snow golems and the endermite have to be aligned against a fence, which the video never mentions.
• The world download posted on the first day had a timing error and was replaced, so make sure you have the fixed one.