marimo

marimo develops the eponymous reactive Python notebook and publishes the official marimo MCP Server, which lets AI agents connect to running notebook sessions. Unlike traditional notebooks, marimo stores its notebooks as pure Python files (.py), making them Git-friendly, reproducible, and executable as standalone scripts or web applications.

Its central feature is reactive execution: when a cell is modified, marimo automatically updates all dependent cells, eliminating the stale-state errors common in traditional notebooks. Built-in interactive elements such as sliders, dropdowns, interactive dataframe tables, and selectable plots make exploratory data analysis easier. The editor offers GitHub Copilot-style autocomplete, vim keybindings, code formatting, and a debugging panel, complemented by a comprehensive CLI plus library and VS Code extension support. First-class SQL support works directly with Polars, Pandas, PyArrow, DuckDB, SQLite, Postgres, and MySQL. Notebooks can be shared as WebAssembly-powered HTML exports or standalone web apps via the marimo CLI.

marimo was founded in 2022 by Akshay Agrawal and Myles Scolnick, based in San Francisco with $5 million raised to date. Agrawal previously worked at Google Brain helping build TensorFlow and holds a Stanford PhD on vector embeddings; Scolnick previously engineered at Palantir and CloudKitchens. The project is fully open source with more than 22,900 GitHub stars; users include Stanford, Johns Hopkins, OpenAI, Shopify, and Pfizer.