wasm2mpy enables developers to write code in statically compiled languages and run it on MicroPython-based embedded systems (such as ESP32, Raspberry Pi Pico, STM32, and nRF52) with near-native performance. Since MicroPython is relatively slow for computationally intensive applications, wasm2mpy provides the tools necessary to run demanding software, such as AI models and signal processing algorithms, more efficiently.

✅ builds and runs OK
🟡 builds OK, doesn't run
🚧 work in progress

• ESP32-C3 160MHz: 179.791
• STM32F405 168MHz: 233.918
• ESP32 240MHz: 228.363
• ESP32-S3 240MHz: 271.573
• BL616 320MHz: 344.293
• iMXRT1062 600MHz: 1911.437
• i5-8250U 1.6GHz: 18696.248

Follow the build instructions

mpremote cp zig.mpy :lib/
mpremote exec "import zig; zig.setup()"
⚡ Zig is running!

For example, test/simple.wasm just adds 2 numbers:

(module
    (func (export "add") (param i32 i32) (result i32)
        (i32.add (local.get 0) (local.get 1))
    )
)

MicroPython v1.24.0-preview.224.g6c3dc0c0b on 2024-08-22; Raspberry Pi Pico W with RP2040
Type "help()" for more information.
>>> import simple
>>> simple.add(3, 4)
7
>>> simple.add(10, 6)
16

>>> import cpp
>>> cpp.setup()
🤩 C++ is running!
>>> cpp._memory[4096:4096+32]
bytearray(b' Blink\x00\xf0\x9f\xa4\xa9 C++ is running!\x00\n\x00\x00\x00')
>>> new_data = b"Hello C++ world"
>>> cpp._memory[4096+12:4096+12+len(new_data)] = new_data
>>> cpp.setup()
🤩 Hello C++ world

The idea is very similar to embedded-wasm-apps:

• Support exports
  • Auto-generate exports bindings
• Support imports
• Support memory
• Support .a inputs for mpy_ld
• XIP for native modules
• TBD: Support globals
• Add RISC-V support: micropython/micropython#15603
• Optimize codegen
  • Use u32 instead of u64 for mem addresses
  • Use a directly addressable .bss section as memory (skip indirection)
• Implement WASM Custom Page Sizes
• Implement WASM Exceptions
• Implement WASM Stack Switching

• Discussions: GitHub, Hacker News
• wasm2c, w2c2
• MicroPython Native Modules
• Feasibility of WASM for MicroPython