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updatedAt: 2025-05-18T13:18:01.000Z
agentTools:
projectIndex: https://docs.hud.io/llms.txt
---
# Use Hud in CI/CD for PR Comparison
# Hud PR Comparison: Your PR Guardian
**We’ve got your back to ensure your changes don’t break production.**
The **Hud PR Comparisons** feature empowers developers to detect performance degradations early in the development process.
### How It Works
Hud compares the performance of new code introduced in a Pull Request (PR) **against the existing code in the main branch**, so you can address potential issues before they reach production.
Once the Hud GitHub App is installed in your repository, **Hud will automatically add a comment to your PR** whenever a performance degradation is detected during the PR’s tests.
### Key Capabilities
1. **Impact Analysis**: Understand how new code in a PR affects endpoint metrics within your service.
2. **Metric Comparison**: Compare critical metrics like P90 duration and error rates between the PR and the main branch.
3. **Proactive Alerts**: Receive detailed PR comments highlighting performance degradations detected during testing.
### Thresholds
Hud will issue a warning about endpoint degradation if the following thresholds are met during a single test job:
* Minimum Degradation Rate: `100%`
* Minimum Number of Invocations: `200`
* Minimum P90 Duration: `200ms`
These thresholds ensure that warnings are raised only for significant and impactful degradations. Let us know if you'd like further refinements!