JupyterLite Officially Joins Project Jupyter!

· Project Jupyter · education JupyterLite WebAssembly

We are thrilled to announce that JupyterLite is now an official part of Project Jupyter. This milestone marks a significant step forward for interactive computing in the browser and strengthens JupyterLite’s role within the Jupyter ecosystem.

What is JupyterLite?

JupyterLite is a JupyterLab distribution that runs entirely in your web browser. Kernels execute directly in the browser using WebAssembly, eliminating the need for an application server. This means:

JupyterLite greatly expands the options available in the Jupyter ecosystem for education, documentation, and demos, where reducing friction is critical.

As Brian Granger reminded us during his JupyterCon 2025 keynote, Jupyter’s mission is “to empower people of all backgrounds to think, collaborate, and share knowledge using computational storytelling.” From this perspective, JupyterLite is a logical and key next step to take, letting Jupyter take advantage of the impressive strides made in recent years by the WebAssembly/JavaScript ecosystem (in reach and capability) to advance this mission. JupyterLite is an excellent complement to other forms of accessing Jupyter (whether through a local Python installation or a hosted infrastructure service), that facilitates new use cases and lowers barriers in many others.

Interactive computing in the browser with JupyterLite

The Journey of JupyterLite

JupyterLite’s development began in 2021, led by Jeremy Tuloup at QuantStack. Over the past four years, it has benefited from the dedication of several other team members, Martin Renou, Trung Le, and Ian Thomas — as well as invaluable contributions from community members like Nick Bollweg and many others.

Beyond the JupyterLite repository, the project includes comprehensive tooling for creating in-browser language kernels based on xeus. These kernels support languages like Python, R, C++, GNU Octave, Lua, and SQLite, sharing the same codebase as their backend counterparts, developed by Thorsten Beier, Isabel Paredes, Johan Mabille, and Antoine Prouvost. These kernels are built upon the emscripten-forge software distribution for WebAssembly. The project also includes a Python kernel based on Pyodide, and kernels for JavaScript and p5.js. This architecture means that the same language-agnostic model for kernels that Jupyter pioneered over a decade ago, carries over to the WebAssembly world.

The JupyterLite GitHub organization also features the JupyterLite Terminal, a terminal and shell emulator that runs entirely in the browser and was developed by Ian Thomas. It enables the use of basic Unix commands like grep, sed, cat, touch, and even vim or nano, all built to WebAssembly.

Screenshot of the JupyterLite terminal emulator, showing some basic Unix commands
The JupyterLite terminal emulator, with basic Unix commands

JupyterLite now powers the official Jupyter website and is used by projects like numpy.org, sympy.org. It also underlies services such as Jupyter Everywhere and notebook.link.

A Natural Fit with JupyterLab

JupyterLite has always been closely tied to JupyterLab. It is increasingly becoming a set of JupyterLab extensions that replace core plugins to manage kernels, settings, and content in the browser. With contributors overlapping significantly with the Jupyter Frontends group, this integration formalizes what many in the community already recognized: JupyterLite is a core part of the Jupyter ecosystem.

The proposal to transfer JupyterLite to the Jupyter governance received strong support from the Jupyter community and by the Jupyter Frontends council.

Better integration with the rest of Jupyter

With JupyterLite now being an official part of Jupyter, it will be easier to find areas for better integration with other aspects of our ecosystem: we can reduce duplication, smooth out the documentation and model for creating and using both “traditional” (server-hosted) and WebAssembly kernels, and make JupyterLite a natural instant-access component of MyST/JupyterBook-based sites, and more.

Mission-wise, JupyterLite is a natural next step for Jupyter, and having it be an official part of the project makes it much easier for the community to integrate its benefits throughout. We hope you’ll try it, use it and contribute to its growth!

Try it in your browser

If you would like to try JupyterLite in your browser, click on the following link:

Try lite now.

Acknowledgments and team credits

JupyterLite’s success is thanks to the support of individuals and organizations who believed in its vision. This includes:

Key developers to this stack include:

Thank you for being part of this journey, we cannot wait to see what you build with JupyterLite!

— this post was coauthored by Jérémy Tuloup, Sylvain Corlay, and Fernando Pérez

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