Template Versioning

Every change to a template's variable definitions is captured as an immutable version. Versions provide a full audit trail and let you compare states, revert to previous configurations, and control when assets are upgraded to newer definitions.

How versions work

Each version is a snapshot of the template at a point in time, including:

• Template metadata (name, alias, category, description)
• All variable definitions (keys, names, data types, units, kinds)
• A version number (auto-incremented starting from 1)
• An optional changelog describing what changed
• A creation timestamp

Versions are never modified or deleted. The history is append-only.

Creating a version

Manual creation

Go to the Versions tab on the template detail page and click New Version. You can optionally enter a changelog message describing what changed.

Automatic creation

Versions are created automatically when you:

• Add variables from a variable library — if the new set of variables differs from the latest version, a new version is created
• Remove variables from the template — a new version is created with the remaining variables

When auto-versioning occurs, a notification confirms the new version number.

Viewing versions

The Versions tab lists all versions in reverse chronological order. Each entry shows:

• Version number (e.g., "Version 3")
• "Latest" badge on the most recent version
• Changelog text (if provided)
• Creation date

Comparing versions

Click Compare on the Versions tab to see the differences between any two versions. Select a "from" and "to" version in the dropdowns.

The comparison shows:

Metadata changes:

• Name, category, or description differences highlighted with old and new values

Variable definition changes:

• Variables added (shown in green with a count)
• Variables removed (shown in red with a count)
• Variables modified (shown in yellow with a count) — includes changes to data type, unit code, kind, or other properties

Reverting to a previous version

To revert, click the Revert button on any version that is not the latest. A confirmation dialog explains what will happen.

The revert process:

1. Copies the metadata and variable definitions from the target version
2. Creates a new version with an incremented version number
3. Updates the template's current state to match

For example, if you are on version 5 and revert to version 3, a new version 6 is created with the same state as version 3. Versions 1 through 5 remain unchanged in the history.

Versions and assets

Assets created from a template are linked to a specific version. When a new version is created, existing assets remain on their current version until you explicitly migrate them. The asset detail page shows a notification when a newer version is available.