// the find
livebook-dev/livebook
Automate code & data workflows with interactive Elixir notebooks
Livebook is a Phoenix LiveView-based notebook application for Elixir — think Jupyter but built on the BEAM, with real-time collaboration baked in and notebooks stored as plain Markdown files. It runs as a local desktop app, a Docker container, or on Fly.io, and lets you attach directly to a running Elixir node, which makes it useful for production introspection, not just data science. The target audience is Elixir developers; Python support exists but is clearly a second-class feature.
The .livemd format is the right call — notebooks are valid Markdown, diff cleanly in git, and are readable without Livebook installed. The custom runtime model is genuinely useful: attaching to an existing node means you can run cells against a live mix project or a remote node, which turns it into a lightweight REPL for debugging production systems. Stale cell tracking (it knows which cells downstream of an edit need re-running) is something Jupyter still gets wrong after a decade. The iframe sandboxing for JS output cells — serving them from a separate port/origin — is real security thinking rather than just hoping users don't embed malicious widgets.
The dual-port architecture (8080 + 8081) is a deployment footgun — putting it behind nginx or a cloud load balancer requires proxying both, and getting the iframe URL env var wrong produces silent failures where visualizations just don't render. Livebook Teams gates most of the interesting multi-user features (shared secrets, deployment groups, audit logs) behind a paid subscription, which makes the OSS version feel like a demo for the SaaS product when you hit those walls. Python support is functional but shallow — you get a Pyodide-style environment that works for toy scripts but falls apart for anything that needs native extensions or a real virtualenv. The collaboration model requires whoever opened the session to keep their instance running; there's no persistent hosted session, so it's not a replacement for Colab in teams that don't run their own infrastructure.