Baseline Builds
How Vera CI selects reference screenshots for visual comparisons.
What is a baseline?
A baseline is the set of approved screenshots that new runs are compared against. When you push a new run, Vera CI finds the most recent approved baseline for each snapshot name and runs a pixel-level diff to detect visual changes.
How baselines are selected
Vera CI selects a baseline by finding the most recent run on the reference branch that meets these criteria:
- Same project
- On the baseline branch (typically your default branch)
- Has been approved (either auto-approved or manually approved)
- Contains snapshots with matching names
Baseline branch
The baseline branch depends on context:
- Pull requests. The PR's base branch (e.g.
main) - Push events. Your project's configured default branch
By default, your repository's default branch is used. You can change this in your project settings.
Auto-approved branches
Runs on your default branch (e.g. main) are automatically approved. This means merging a PR immediately creates a new baseline for future comparisons.
You can configure additional auto-approved branches (like develop or staging) in your project settings.
Orphan builds
When no baseline exists for a snapshot, the run is marked as an orphan build. This is normal for:
- The first run in a new project
- New snapshot names that have never been captured before
- Branches created before any baselines were established
Tip