Version history and undo

flowss keeps several safety nets under your work, each for a different kind of "I want that back". Undo takes back your last few actions in the studio you are in. Each studio keeps a version history of its documents. The Library keeps a history of every document whatever studio made it. The Vault holds named checkpoints of a studio's open document that you can restore whenever you like. The trash holds deleted documents for 30 days. And a backup file holds everything, outside any browser. This page explains each one, how to use it, how much it keeps, whether it follows you to other devices, and which to reach for when.

At a glance

Undo and redo

Every studio has undo and redo for the document you are working on:

The island layout also puts Undo and Redo buttons in the view controls at the bottom right. In the code editors, ⌘Z belongs to the editor while your cursor is in the code.

How far back undo goes:

Undo history belongs to the open tab (except in Sketch). It does not survive closing the tab and does not sync. For anything older, use a version history or the Vault.

See Keyboard shortcuts for every studio's keys.

The Library's document history

Every document in the Library, from any studio, has a version history. It is the answer to "what did this look like last Tuesday?" even for a document you have not opened since.

What is recorded

• When a document is created, its first state is recorded ("created").
• When it changes, the state before your first change is kept ("before this edit"), then each settled change after that ("edited"). A studio with a document open writes your edits back to the Library every few seconds, and each change that actually alters the document becomes a version. Opening, selecting or moving the view without changing anything records nothing.
• When you restore, the state just before the restore and the restored state are both recorded ("before restore", "restored"), so a restore can itself be undone.

Opening a document's history

1. In the Library, open the document's … menu (in grid or list view) and choose History….
2. The dialog is titled **History — *title***. It says how many versions are kept: "*N* versions kept, newest first. Restoring one keeps this document where it is and records what it looked like first, so a restore can itself be undone."

Each version shows:

The summary reads diagrams, Weave canvases and Sketch boards by their structure (nodes, connections, elements) where it can, and falls back to a line-by-line comparison for other documents. If two versions cannot be compared it says "Too large to compare." or "Changed.".

With no versions yet, the dialog says "No versions kept yet. This document's history starts the next time it is edited — every settled change from then on is a version you can come back to."

Restoring a version

1. Click Restore on the version you want. The button changes to Confirm. The newest version (marked current) has no Restore button, and neither does a version too large to keep.
2. Click Confirm to restore. Clicking elsewhere cancels.

The document's content goes back to that version, in place: it keeps its title, tags, star, lineage and Library position, and stays attached to its studio. The dialog stays open with the new versions added on top, so you can undo the restore by restoring "before restore". A toast confirms "Restored title to an earlier version". Close the dialog with Close.

How much is kept

The Library's document history is kept in this browser and does not sync, and it is not included in a backup file. Deleting a document forever (or emptying the trash, or letting the 30-day sweep remove it) also deletes its history.

The Studio's Diagram timeline and History strip

The Studio keeps two histories of each figure, independent of each other and of the Library's:

• Diagram timeline (the rail's Diagram timeline, the ⋮ menu's Version history…, or ⇧⌘H). Records a version about 1.5 seconds after you stop typing and keeps up to 50 per figure. You can name a version, which pins it for good, compare any version with the canvas side by side, see an inline diff, and Restore. Explain change in the comparison asks AI to summarise what changed in meaning, and needs AI on your plan.
• History in the code sheet's footer ("History — versions of this figure, recorded as edits settle; click one to diff or restore"). Records a version about three seconds after edits settle, and on every figure switch, keeping up to 100 per figure. Click a version to see what changed since, then Restore; the current state is recorded first, and the restored state is labelled Restored. A toast confirms "Version restored — the replaced state was recorded first".

Both are kept in this browser per figure and do not sync. Every control is documented in Data, timeline, TikZ and the diagram tools.

Version history in the other studios

See each studio's page for the details: Weave, Lab, BPMN, Sketch.

The Vault: checkpoints you name

The Vault is a set of named checkpoints. A checkpoint is a frozen copy of everything a studio keeps for its open document, which you can restore at any time. It is the way to keep more than one version of a studio that holds one document at a time, and the one history that follows you to your other devices.

The Vault works with Weave, Science, BPMN, the Lab, Sketch and Figure. The Studio keeps a real list of figures, and Study and Evidence keep their work elsewhere, so they have nothing to checkpoint; asking says "This studio keeps its own library, so there is nothing here to checkpoint."

Saving a checkpoint

1. In Weave, Science, BPMN, the Lab, Sketch or Figure, open the Flow Dock with ⌘J (Ctrl+J) or its floating pill.
2. In the Vault section, type a name in the box (its placeholder suggests one from your document, "Save "*title*"…"), or leave it to use that suggestion.
3. Click Save or press Enter.

The Flow Dock confirms "Checkpoint saved — "*name*" can be restored anytime". You can also save from ⌘K with Save document to Vault.

The save box appears only in a studio whose document can be checkpointed. With no checkpoints yet, the dock's Vault section reads "Snapshot this document to keep more than one on this canvas." in those studios, and "Checkpoints you save from Weave, Science, BPMN, Lab, Sketch and Figure appear here — your living documents live in the Library." everywhere else.

What a checkpoint includes depends on the studio, and is always the whole document:

Some checkpoints are made for you:

• Sketch saves an Auto checkpoint as you work, at most once every five minutes and only when the board has changed, and keeps the ten most recent auto checkpoints. Checkpoints you save yourself are never pruned this way.
• Cloud sync keeps both copies when a studio's document changed on two devices: one stays live and the other is saved as "*document* — this device's copy" or "*document* — copy from another device". See Cloud sync, offline work and devices.
• Science sets your own figure aside as a checkpoint when you join someone else's live session from a link, and tells you its name.
• Restoring saves what it replaces first (below).

Restoring a checkpoint

Click a checkpoint's name in the Flow Dock's Vault list or the Library's Vault band (the tooltip says "Restore into *studio*"), or pick it in ⌘K. The Flow Dock lists your six newest checkpoints and the Library band your eight newest; ⌘K searches further back, among your most recent work.

1. flowss first checkpoints the document that is open in that studio, under the name "Before restoring "*name*"" (where name is the checkpoint you are restoring), unless nothing would be lost (the studio is empty, the restore changes nothing, or the open document is already in the Vault exactly). If the Vault is full, this safety copy may remove the oldest checkpoint to make room, and the confirmation says so.
2. It writes the checkpoint back and opens the studio.
3. On arrival a toast confirms: "Restored "*name*"", adding "— the document it replaced is in the Vault as "Before restoring …"" when a safety copy was made.

If the open document cannot be checkpointed first (too large, or no room in the Vault), nothing is restored, so nothing is lost: "Nothing was restored — the document open there could not be checkpointed first (it is too large, or the Vault had no room for it), and restoring would have replaced it for good. Export it or start a new document there, then restore."

A restore detaches the studio from any Library document it had open, so the restored content is never written into the wrong document. Sketch restores in place from its History panel.

Deleting a checkpoint

Hover a checkpoint and click its bin icon ("Delete "*name*" from the Vault"). The toast says "Deleted "*name*"" with Undo for six seconds. Deleted checkpoints stay deleted on your other devices too.

Vault limits

The trash

Deleting a Library document moves it to the trash rather than destroying it.

The trash view says "Documents stay here for 30 days after deletion, then they're removed for good. Restoring puts one back exactly where it was." Each row shows the studio, when it was deleted, its size, and how many days it has left ("removed on the next sweep" when its time is up). Search filters the trash by title.

How the 30 days work: documents in the trash for more than 30 days are removed for good the next time you open the Library. A document deleted forever stays deleted on your other devices, unless it is edited again somewhere after it was deleted.

On a free account, Restore is refused if the document's studio already holds 3 documents, with "… stays in the trash for now: this studio already holds 3 of the 3 figures a free account keeps, and nothing there has been touched. Move one of the open figures to the trash to make room, or upgrade to Starter for unlimited figures."

Cloud projects do not go to the trash. Deleting one is permanent for everyone it is shared with, and asks first. See Your library.

Backups as history

Export library… (Library → Library options (⋮)) saves every Library document, including the trash, to a dated file such as flowss-library-2026-10-04.json. Import backup… merges it back without overwriting anything you edited more recently. Keep a backup before large reorganisations, before clearing site data, or simply on a schedule; it is the one copy that does not depend on any browser or account. See Your library.

A backup holds each document as it is now. It does not carry the Library's version history or your Vault checkpoints, so it is a snapshot of the present rather than a record of the past. Export again whenever you want another point in time.

Which one should I use?

Tips

• Checkpoint before big changes. A named Vault checkpoint takes two seconds and is the one version that follows you to your other devices.
• Name the versions that matter. In the Studio's Diagram timeline and in Weave's Version history, a named version is easy to find later; in the Studio it is also kept for good.
• Restores are safe to try. The Library, the Studio, Weave and the Vault all record the current state before restoring, so you can go back again.
• Empty the trash to free space. Trashed documents keep their full content until they are removed, and count against browser storage.
• Use the right history for the right question. Undo is for minutes, versions are for hours and days, the Vault is for milestones, a backup is for safekeeping.

Limits and known constraints

• Undo history lasts only while the tab is open, except in Sketch.
• The Library's document history keeps 20 versions for each of your 40 most recently changed documents, stays in this browser and does not sync.
• Versions larger than about 120,000 characters are listed but cannot be restored from the Library's history.
• The Studio's Diagram timeline (50 per figure) and code sheet History (100 per figure) are per browser.
• The Vault holds 40 checkpoints and about 400,000 characters per checkpoint; saving into a full Vault removes the oldest.
• The trash keeps documents for 30 days; cloud projects are not trashed.
• Weave's version history, Lab revisions, BPMN versions and Sketch history are each studio's own, kept in this browser.
• Sketch's version history, and the Weave, Lab and BPMN studios themselves, need Starter or above.

Troubleshooting

Related pages

• Your library
• Cloud sync, offline work and devices
• Moving work between studios
• Data, timeline, TikZ and the diagram tools
• Keyboard shortcuts
• A tour of the workspace
• Sketch
• Weave
• Continuum: the one-platform layer