PR Open to First Review Time (PRRT)
PR Open to First Review Time (PRRT) measures the elapsed time between a pull request being opened and the first substantive reviewer comment or approval. It highlights responsiveness in the review process and indicates whether feedback loops keep pace with development flow.
Calculation
PRRT is typically reported weekly or per sprint, using timestamps of PR open events and the first meaningful review action.
The metric is calculated as:
PRRT = average time from PR open to first review feedback (hours or days)
Goals
PRRT helps teams identify bottlenecks in review cycles and ensure timely feedback. It answers questions like:
- Are pull requests sitting idle before anyone reviews them?
- Are developers waiting long enough that flow is disrupted?
- Is something in the review process causing avoidable delays?
Timely review supports rapid iteration and reduces context switching, helping avoid issues like Slow Review Cycles and stalled workflows.
Variations
PRRT may also be referred to as Time to First Review or First Response Time. Common segmentations include:
- By reviewer assignment method, e.g. auto-assigned vs manually selected
- By team or service, to compare review responsiveness across groups
- By PR size, to see whether larger PRs wait longer for feedback
- By time of day, revealing gaps in coverage or team coordination
Tracking these variations helps pinpoint process gaps such as under-resourced reviewers or imbalanced workloads.
Limitations
PRRT captures responsiveness but not quality of feedback. A fast but superficial review may not help and could create false confidence. It also depends on meaningful review actions being captured, automated approvals or silent merges may skew results.
To fully understand review health, pair PRRT with:
| Complementary Metric | Why It’s Relevant |
|---|---|
| Substantive Reviews | Ensures early feedback includes code insights, not just rubber-stamp approvals |
| Pull Request Size | Reveals if larger PRs cause review delays |
| Post PR Review Dev Day Ratio (PRR) | Shows whether faster reviews help developers re‑enter flow quickly |
Optimization
Improving PRRT can significantly boost developer flow and collaboration efficiency:
- Define Code Review Standards that clarify expected review response times and outcomes
- Set review SLAs so PRs are assigned and reviewed within a predictable window
- Balance reviewer workloads to avoid bottlenecks from overcommitment or uneven distribution
- Use notifications or bots to surface newly opened PRs and prompt reviewer attention
- Break down large PRs so they can be reviewed faster and more effectively
PRRT shines when reviews arrive promptly with substance. When review cycles are fast and meaningful, developers stay in flow and iteration cycles shorten. Monitoring and improving PRRT ensures team momentum and keeps delivery aligned with expectations.
