Optimize MERN Backend Speed

My MERN site loads far too slowly and I’ve traced the issue to the Node.js backend rather than the React front-end. I’d like you to dive into the server-side code, pinpoint the bottlenecks, and implement fixes that cut initial page-load time by at least half.

What you’ll be working with
• Node.js (Express and MongoDB are in the stack, but the focus is firmly on the Node layer).
• Existing codebase on GitHub, deployed on a small VPS with PM2.

Scope of work
– Profile the current API and middleware flow to surface blocking operations, heavy synchronous logic, and chatty database calls.
– Optimise routing, controller logic, and query patterns; introduce caching or background jobs where useful.
– Apply best-practice techniques such as gzip compression, HTTP/2 where possible, connection pooling, and asynchronous patterns.
– Document each change so I understand what was done and why.

Acceptance criteria
1. Time to First Byte reduced by at least 50 % on Lighthouse and GTmetrix.
2. No new regressions in functionality or failing tests.
3. A concise report outlining discoveries, changes applied, and next-step recommendations.

Please share a brief note on similar Node.js performance work you’ve completed and your estimated turnaround time.