I built W4ME Station, a WASM-4 runtime for old Java ME phones.

It runs standard WASM-4 cartridges on devices that support CLDC 1.1 and MIDP 2.0. The runtime includes a WebAssembly interpreter, graphics, audio, input, persistent storage, and support for loading external cartridges.

The full application, including 13 bundled cartridges, fits into a JAR of about 275 KB.

I started this to see whether an unchanged WASM-4 cartridge could run on memory-constrained Java ME hardware. I’d be interested in feedback on the interpreter, cartridge compatibility, and real devices worth testing.