Pyodide

Pyodide is a Python distribution for the browser and Node.js based on WebAssembly.

What is Pyodide?

Pyodide is a port of CPython to WebAssembly/Emscripten.

Pyodide makes it possible to install and run Python packages in the browser with micropip. Any pure Python package with a wheel available on PyPi is supported. Many packages with C, C++, and Rust extensions have also been ported for use with Pyodide. These include many general-purpose packages such as regex, PyYAML, and cryptography, and scientific Python packages including NumPy, pandas, SciPy, Matplotlib, and scikit-learn.

Pyodide comes with a robust Javascript ⟺ Python foreign function interface so that you can freely mix these two languages in your code with minimal friction. This includes full support for error handling (throw an error in one language, catch it in the other), async/await, and much more.

When used inside a browser, Python has full access to the Web APIs.

Try Pyodide

Try Pyodide in a REPL directly in your browser (no installation needed).

What should I look at first?

• If you wish to use a hosted distribution of Pyodide: see the Getting started documentation.

• If you wish to host Pyodide yourself, you can download Pyodide from the releases page and serve it with a web server.

• If you wish to use Pyodide with a bundler, see the documentation on Working with Bundlers.

• If you are a Python package maintainer, see the documentation Building and testing Python packages out of tree.

• If you want to add a package to the Pyodide distribution, see the documentation on Adding a package to the Pyodide Distribution.

• If you wish to experiment or contribute back to the Pyodide runtime, see the documentation on Building from source.

Table of contents

Using Pyodide

• Getting started
• Downloading and deploying Pyodide
• Using Pyodide
• Accessing Files Quick Reference
• Loading packages
• Building and testing Python packages out of tree
• Pyodide Python compatibility
• Type translations
• Interrupting execution
• Redirecting standard streams
• API Reference
• Frequently Asked Questions
• Community Examples

Development

The Development section helps Pyodide contributors to find information about the development process including making packages to support third party libraries.

Development

• Adding a package to the Pyodide Distribution
• Building from source
• Testing and benchmarking
• Debugging tips
• How to Contribute

Project

The Project section gives additional information about the project’s organization and latest releases.

Project

• What is Pyodide?
• Roadmap
• Code of Conduct
• Governance and Decision-making
• Change Log
• Related Projects

Communication

• Blog: blog.pyodide.org

• Mailing list: mail.python.org/mailman3/lists/pyodide.python.org/

• Gitter: gitter.im/pyodide/community

• Twitter: twitter.com/pyodide

• Stack Overflow: stackoverflow.com/questions/tagged/pyodide