Paid Media
5 min read
• Published Dec 8, 2025
Building High-Performance Edge SSR with Cloudflare HTMLRewriter
AL
Alex Rivera
Author & Contributor
How we achieved sub-10ms response times globally by transforming streaming HTML directly in Workers without heavy Node.js SSR runtime overhead.
Server-Side Rendering (SSR) traditionally meant running Node.js servers, rendering React or Vue components to string, and shipping HTML to the client. While powerful, this approach often introduces cold starts and increased latency on global edge networks.
With Cloudflare HTMLRewriter, we stream HTML directly from static edge storage and rewrite DOM nodes on the fly with real-time data from Cloudflare D1. This yields ultra-fast response times globally.
Key Advantages of Edge HTMLRewriter SSR:
1. Zero Node.js runtime overhead: HTMLRewriter operates in Rust/C++ inside V8 isolates.
2. True streaming: Responses begin sending to the browser instantly before the full payload is generated.
3. SEO Friendly: Search crawlers receive complete, fully formed HTML markup with rendered titles, meta tags, and structured content.
4. Seamless Dashboard Authoring: Articles published from the admin dashboard immediately reflect across edge nodes.