Key concepts

A project is a folder of FreeCAD documents that are versioned together: every .FCStd file in the folder and its sub-folders. An assembly and the parts it links to therefore always match at every point in history.

Turning on version control creates a hidden .strata folder inside the project folder. It holds the history; your .FCStd files stay ordinary FreeCAD files. Moving or copying the whole project folder, .strata included, keeps the history.

Every time you save a document in a project, Strata records a history entry with the date, your name, the documents that changed and a plain-language description of the change:

The description comes from comparing the FreeCAD model itself, feature by feature. FreeCAD’s internal bookkeeping is left out, so you only see what you changed.

A version is a named, permanent snapshot of the whole project, for a milestone: V1 – Initial concept, V2 – Prototype sent to supplier. Versions can be viewed, compared, restored, branched from and released. Names must be unique; Strata suggests the next Vn.

A workspace is a separate line of work. Every project starts with the workspace Main. Create a workspace to try an alternative, for example a lighter bracket, without touching Main. Switching workspaces updates the documents on disk and reloads the open ones in FreeCAD. When the alternative is good, merge it into Main; if not, simply switch back and leave it.

Nothing is ever deleted by Strata’s normal operations. Documents that disappear during a restore or workspace switch are moved to .strata/trash.

Compare shows what changed between any two points: added, deleted and edited features with their old and new values, grouped by document. For a single document it can also overlay both states in 3D, the earlier one in translucent red and the later one in blue, and report the volume change.

Merging brings the changes of one workspace into another, document by document:

A release makes a version official, for example for manufacturing. Each released document gets a part number and a revision letter. Revision letters follow ASME Y14.35 practice: A, B, C, …​ skipping I, O, Q, S, X and Z, then AA, AB, …​

A release can go straight to Released, or through an approval step: Pending, then Released or Rejected. A released revision that is no longer valid is marked Obsolete.

A project can be shared through a network folder, a synced drive (OneDrive, Nextcloud, Dropbox) or a Git server. Sync sends your workspaces, versions and releases there and fetches your colleagues'. Everything works offline; sync whenever the shared location is reachable.

For readers who know Git: Strata is a thin, careful layer over it.

See How history is stored for the details.