Alex recompiled the 1.12 client using a custom TeaVM fork targeting Wasm GC. Instead of outputting JavaScript heap management, every object allocation, every new BlockPos() , every HashMap of entities — all became Wasm GC structs and arrays, traced and collected by the browser’s optimized garbage collector.

The first test was a superflat world with 64 villagers. On the JS backend, frame rate dropped to 15 FPS with major GC spikes every 5 seconds. On Wasm GC? A steady 45 FPS. No visible hitches. The collector ran concurrently, reclaiming entire chunks of blocks and entity pathfinding data without stopping the world — in both senses.

Then came the experiment: .

Alex grinned. Eaglercraft 1.12 with Wasm GC wasn’t just a tech demo. It proved that full legacy Minecraft could live forever, directly in browsers, with near-native performance — no plugins, no downloads, no Java runtime.

And the browser’s garbage collector just hummed along, quietly collecting fallen leaves in the background.