> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fabro.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# Immutable workflow versions

## Store validated workflow packages by content

The API can now validate and store an immutable workflow package with its entrypoint, files, and exact child-workflow dependencies. Repeating the same canonical package returns the same SHA-256 workflow version ID.

```http theme={"languages":{"custom":["/languages/dot.json","/languages/fabro.json"]}}
POST /api/v1/workflow-versions
```

## More

<Accordion title="API">
  * Invalid workflow-version content and missing or non-canonical dependencies return `422` errors
  * Workflow version IDs are accepted case-insensitively and returned in canonical lowercase form
</Accordion>

<Accordion title="Fixes">
  * Workflow-version validation now detects file path collisions that were previously hidden by sort order
</Accordion>