Expert React + Node.js Developer to Fix Migration Issue

I need an experienced React and Node.js developer to resolve a migration issue causing random application crashes.

Key Requirements:

Strong expertise in React.js (hooks, state management)
Proficient in Node.js (Express framework)
Experience with data/codebase migration
Quick bug identification and resolution
Good communication skills

Bonus Skills:

MongoDB or PostgreSQL experience
Deployment familiarity (Heroku, AWS, Vercel)
Version control knowledge (Git)

Project Scope:

Diagnose and resolve migration issue
Ensure front-end and back-end functionality post-fix
Test for regressions and confirm deployment success

Timeline: ASAP — Ideally within 1–2 days