W4ME Station 1.0.0 enables WASM-4 games on Java ME phones

WASM-4 Games on Legacy Devices

W4ME Station 1.0.0 has been released, bringing WebAssembly (WASM-4) games to Java ME phones. This runtime allows users to play unmodified WASM-4 cartridges on devices supporting CLDC 1.1 / MIDP 2.0, which includes feature phones from the mid-2000s. The release package, including thirteen bundled cartridges, is under 300 KB.

Technical Implementation

The W4ME Station runtime operates without a Just-In-Time (JIT) compiler and does not require a network connection for its bundled library. It features validated WebAssembly execution with a persistent fixed-width W4IR cache. The project implements WASM-4 host APIs for graphics, input, audio, disk, text, and tracing.

Features and Compatibility

The software supports various input methods, including phone keys, keyboard controls, pointer input, and an on-screen touchpad for touchscreen devices. It also provides per-cartridge persistent disk storage with checksummed RMS generations and sampled MMAPI audio with streamed MIDI. Two build variants are available: a base build for devices without the optional FileConnection API and a full build for those with JSR-75 FileConnection support. Installation involves downloading matching .jad and .jar files and opening the .jad from the phone's application manager.

Development Environment

Development of W4ME Station requires a Linux environment with `just`, Podman, and Distrobox. The project toolchain includes JDK 8, ProGuard, KEmulator, WABT, and other utilities, with version-sensitive components pinned by the container definition. Java sources and classfiles are pinned to Java 1.3.