marimo
Reactive Python notebook stored as a plain file, with no hidden execution state.
why this verdict
Keep it — Anthropic has not replaced it
Anthropic's version overlaps, but does not finish the data & BI job, so this one is still worth keeping open.
- A named launch, not a vibe named, unlinked
- Jupyter's overwhelming installed base and AI notebooks from cloud vendors. Anthropic, July 8, 2025 — no announcement link recorded yet.
- How much of the job it covers not the job editorial call
- Parts of it. The job still needs the tool to get finished.
- Is there a free way to do it? yes
- 3 of 3 listed replacements have a usable free tier: Jupyter, Deepnote and Hex.
- What the call is worth nothing to cancel
- No paid entry tier tracked, so there is no subscription to cancel.
- Threatened by
- Anthropic
- Since
- July 8, 2025
- List price
- free
- Per year
- —
The backstory
marimo fixes the defect every data scientist complains about in Jupyter: hidden state, where cells run out of order and a notebook that works on your machine is irreproducible everywhere else. marimo notebooks are reactive, so changing a cell updates everything downstream, and they are stored as plain Python files that diff properly in git. That last property matters more each month, because an agent editing a notebook needs a format that reviews like code.
Escape hatches
The standard with by far the largest ecosystem
jupyter.org open_in_newCollaborative cloud notebooks with AI features
deepnote.com open_in_newNotebook and app builder for data teams
hex.tech open_in_new3 of 3 replacements have a usable free tier.