Prompt

Identify what caused a performance regression in my application.

<performance_metrics>
Before: {baseline metrics}
After: {degraded metrics}
</performance_metrics>

<recent_changes>
{list recent commits or deployments}
</recent_changes>

<profiler_data>
{paste profiler output if available}
</profiler_data>

Find:
1. Root cause of regression
2. Specific code changes responsible
3. Performance fix options
4. Prevention strategies