PERF-001
Slow server response
MediumDefault severity · Performance · SEO, quality and performance
Last reviewed
What it checks
Server response time (first byte after the connection is ready, so DNS, TCP and TLS are excluded), sampled up to three times; only reported when every sample is slow, so a single cold start or network blip is not blamed on the site.
Why it matters
A slow first byte delays everything else and pushes Largest Contentful Paint past 2.5 seconds.
Recommended fix
Cache or statically render the page, move slow data fetching off the critical path, and host near your users.
How to verify
Run a speed test from your users’ region and confirm TTFB is under 800 ms.
Example fix prompt
Generic prompt (your report adds the evidence)
Please fix this production issue in my app.
Issue PERF-001: Slow server response
Site: https://your-app.example
First confirm the issue in the code or live config. If it is not present, say so and change nothing.
Task: The homepage takes too long to send its first byte. Make the page static or cached where possible (static generation or a CDN cache header), move slow database or API calls out of the initial render or run them in parallel, and avoid blocking work in middleware.
Constraints: make the smallest change that fixes this, keep the current design and behaviour, never paste secret values into code or chat, and tell me which files you changed.
Done when: Run a speed test from your users’ region and confirm TTFB is under 800 ms.