Last updated: July 31, 2026

TL;DR: We’re changing molab’s storage model. Notebooks will now persist only your source files, and files in the storage/, public/ and layouts/directories; persisted storage across these directories will be limited to 1GB and 15,000 files. You’ll have a six week grace period to move important files into these directories or external storage. Effective immediately, workspace files greater than 1GB will not be persisted.

Earlier this summer we introduced free GPU support on molab. It has been amazing to see the sorts of workloads this has enabled on our platform and the growth in user adoption. More load on the system has also meant more complex engineering challenges. Our storage model, particularly, has proven to be the most challenging. We are currently very generous with the amount of data we allow users to store in their notebook environment. However, massive file volumes began affecting notebook startup times, data durability, and general reliability. For our users, this means a surprising and oftentimes frustrating experience.

To remedy these issues, we are changing how storage is managed.

What’s changing?

Cap on file syncs

Starting Aug 1, 2026 all files larger than 1GB will not be saved on teardown. You can still download the files into the notebook and use them in molab, however, they will not be persisted on notebook shutdown. The majority of the files we’ve seen at this size are downloadable artifacts such as HuggingFace models and datasets. We think that, on balance, managing files of this size and magnitude degrades the notebook experience. We realize that this change is destructive for some users. If you have a use case that requires storing files outside of this limit please email us.

Explicit save folders

To keep your workspaces fast and prevent temporary build artifacts, model caches, and temporary files from clustering your persistent data, all notebooks will now come with an explicit persistence folder called `storage`. To be clear, the following will persist across sessions:

• Your code: the notebook files (notebook.py and other source files in the marimo folder)
• Anything in the `storage` folder
• Web assembly exports: Files stored in `public/` and `layouts/`

Limits on the `storage` folder

For now, the storage folder will hold a maximum of 1GB of total data and a maximum of 15,000 files. By establishing clear caps, we can guarantee faster notebook load times, and predictability every time you start a notebook. We’ll continue adjusting these limits based on how people use molab to keep the service sustainable.

Bring your own remote storage

If your storage needs exceed our limits, or if you need to access the same data across multiple notebooks, we recommend connecting your notebooks to your own remote cloud storage or Google Drive.

Clear, in-app feedback

In the past, storage checks happened asynchronously in the background. Large file volumes failed silently and users lost data without warning. In the future, exceeding file limits will give an explicit warning.

Timeline and next steps

We want to give everyone plenty of time to organise their files and adjust to the new workflow.

• 1.5-Month Grace Period: You have 6 weeks (1.5 months) from today to review your current notebooks and move any essential datasets or output artifacts that are under 1GB into your designated persistent directory (e.g., /storage).
• In-App Notices: Look out for helpful banners in your notebook edit view over the coming days guiding you through your current usage and migration options.

We’re making these changes so molab can remain fast, stable, and reliable as your workloads grow. If you have edge cases or need higher capacity for specialized projects please reach out to us!