Backend server performance

Purpose

Explain why Speed Layer does not directly improve backend server performance, and how to think about TTFB.

What backend performance means

Backend performance includes:

• Server response time
• API latency
• Database and application performance
• CDN caching and origin configuration

A common metric associated with this is Time to First Byte (TTFB).

Background:

• web.dev: TTFB https://web.dev/ttfb/

What Speed Layer can do

Speed Layer runs in the browser after the HTML begins loading. It can improve:

• How quickly important page content becomes visible
• How much third party work competes with rendering
• How responsive the page feels during early interactions

What Speed Layer does not do

Speed Layer does not:

• Make your server respond faster
• Fix slow API calls
• Change origin infrastructure
• Replace CDN caching configuration

If TTFB is slow, improvements usually require work on hosting, caching, application code, or upstream services.

Related pages

• What is TTFB (Time to First Bite)?
• How Speed Layer Improves Page Load Speed
• What Speed Layer Does and Does Not Do