TTFB 820ms -> 90ms on a SaaS marketing site

TTFB 820ms -> 90ms on a SaaS marketing site
TTFB = time to first byte. Every page was rendered server-side per request on a single origin in Virginia.
— EU p75 TTFB was 1,140ms (extra round trips + cold PHP).
— Put the marketing pages behind a CDN with full-page cache, 5-min TTL, stale-while-revalidate.
— Cache hit ratio settled at 96%. Origin requests dropped 24x.
Before | After
p75 TTFB EU: 1,140 | 110
p75 LCP: 3.2s | 1.4s
Takeaway: 730ms shaved off TTFB without touching application code.