Small Embeddable WebAssembly Runtime
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Wasmjit is a small embeddable WebAssembly runtime. Its core is written in C90 and is easily portable to most environments.

It includes an Emscripten-compatible host environment for running on POSIX systems. This is useful for running WebAssembly modules without having to run an entire browser or JavaScript runtime.

Wasmjit is licensed under a permissive MIT license.

Getting Started

Wasmjit currently runs on x86_64 POSIX systems, like Linux, macOS, and the BSDs. To get started with Wasmjit you need a few tools:

  • A standard POSIX C development environment that includes cc and make.
  • Emscripten SDK

Building the Executable

$ make clean
$ make -j wasmjit

Building and running the Example

$ source path_to_emsdk/ # bring emcc into $PATH
$ emcc -o selfpipe.js src/wasmjit_examples/selfpipe.c

You can now run the example:

$ time ./wasmjit selfpipe.wasm


Wasmjit can run a fairly large subset of Emscripten-generated WebAssembly and has been tested on Linux, OpenBSD, and macOS. It currently only supports x86_64. Here are the current developments goals in order of priority:

  • Implement an interpreter
  • Implement Go-runtime for Go-generated wasm files
  • Optimize x86_64 JIT
  • Implement arm64 JIT
  • Implement JIT debugging symbols

PRs are welcome :) see first.


Rian Hunter @cejetvole