wasmer run tokera/rustpython


A Python-3 (CPython >= 3.5.0) Interpreter written in Rust 🐍 😱 🀘.

Build Status codecov License: MIT Contributors Gitter dependency status WAPM package Open in Gitpod


Check out our online demo running on WebAssembly.

RustPython requires Rust latest stable version (e.g 1.38.0 at Oct 1st 2019). To check Rust version: rustc --version If you wish to update, rustup update stable.

To test RustPython, do the following:

$ git clone
$ cd RustPython
$ cargo run
Hello, RustPython!

Or use the interactive shell:

$ cargo run
Welcome to rustpython
>>>>> 2+2

You can also install and run RustPython with the following:

$ cargo install rustpython
$ rustpython
Welcome to the magnificent Rust Python interpreter

Or through the conda package manager:

$ conda install rustpython -c conda-forge
$ rustpython


You can compile RustPython to a standalone WebAssembly WASI module so it can run anywhere.

$ wapm install rustpython
$ wapm run rustpython
>>>>> 2+2

Building the WASI file

You can build the WebAssembly WASI file with:

cargo build --release --target wasm32-wasi --features="freeze-stdlib"

Note: we use the freeze-stdlib to include the standard library inside the binary.

Embedding RustPython into your Rust Applications

Interested in exposing Python scripting in an application written in Rust, perhaps to allow quickly tweaking logic where Rust's compile times would be inhibitive? Then examples/ and examples/ may be of some assistance.


RustPython is in a development phase and should not be used in production or a fault intolerant setting.

Our current build supports only a subset of Python syntax.

Contribution is also more than welcome! See our contribution section for more information on this.

Conference videos

Checkout those talks on conferences:

Use cases

Allthough rustpython is a very young project, it is already used in the wild:


  • Full Python-3 environment entirely in Rust (not CPython bindings)
  • A clean implementation without compatibility hacks


Currently along with other areas of the project, documentation is still in an early phase.

You can read the online documentation for the latest release.

You can also generate documentation locally by running:

$ cargo doc # Including documentation for all dependencies
$ cargo doc --no-deps --all # Excluding all dependencies

Documentation HTML files can then be found in the target/doc directory.


Contributions are more than welcome, and in many cases we are happy to guide contributors through PRs or on gitter. Please refer to the development guide as well for tips on developments.

With that in mind, please note this project is maintained by volunteers, some of the best ways to get started are below:

Most tasks are listed in the issue tracker. Check issues labeled with good first issue if you wish to start coding.

Another approach is to checkout the source code: builtin functions and object methods are often the simplest and easiest way to contribute.

You can also simply run ./ to assist in finding any unimplemented method.

Using a standard library

As of now the standard library is under construction. You can use a standard library by setting the RUSTPYTHONPATH environment variable.

To do this, follow this method:

$ export RUSTPYTHONPATH=~/GIT/RustPython/Lib
$ cargo run -- -c 'import xdrlib'

You can play around with other standard libraries for python. For example, the ouroboros library.

Compiling to WebAssembly

See this doc


Chat with us on gitter.

Code of conduct

Our code of conduct can be found here.


The initial work was based on windelbouwman/rspython and shinglyu/RustPython


These are some useful links to related projects:


This project is licensed under the MIT license. Please see the LICENSE file for more details.

The project logo is licensed under the CC-BY-4.0 license. Please see the LICENSE-logo file for more details.

A Python-3 (CPython >= 3.5.0) Interpreter written in Rust 🐍 😱 🀘