A secure web app for instantly sending text and files between your devices. Built to demonstrate production-ready engineering patterns for co-op interviews.
This isn't just another CRUD app. ctrl+w demonstrates real engineering challenges that come up in production systems.
Access & refresh tokens with secure rotation, bcrypt hashing, and role-based access control.
Bidirectional sync using Socket.io rooms. Handle disconnections, reconnections, and race conditions.
6-digit pairing codes, auto-expiring sessions, and background cleanup jobs using cron.
Cloudinary integration with 4MB limits, secure upload handling, and automatic cleanup.
Comes with system design docs, whiteboard diagrams, and 20+ technical Q&A for interviews.
Jest tests, ESLint, CI/CD with GitHub Actions, and Vercel deployment ready.
A carefully chosen stack that mirrors what companies actually use in production.
This project was architected collaboratively with Claude (Anthropic's AI assistant) to ensure every design decision is intentional, well-documented, and interview-ready.
Every non-trivial piece of code includes explanations, diagrams, common pitfalls, and exercises — turning this project into both a portfolio piece and a learning resource.
Every feature maps to real interview questions and system design discussions.
Pairing codes, session lifecycle, real-time sync architecture, and scalability considerations.
JWT rotation, bcrypt, input validation, rate limiting, and secure file uploads.
WebSocket handshakes, room management, handling disconnections, and state synchronization.
MongoDB schemas, indexing strategies, TTL for auto-expiry, and efficient queries.
GitHub Actions, environment management, Jest testing, and Vercel deployment.
Cron scheduling, cleanup tasks, handling expired sessions, and file garbage collection.
Check out the GitHub repo for full source code, documentation, and interview prep materials.