I build production-grade backend systems with a strong focus on
correctness, security, performance, and clean architecture.
I’m a Backend Software Engineer with ~2 years of professional experience,
currently focused on deepening my backend & system design expertise while expanding into AI engineering.
My learning style is:
- Build first
- Understand internals
- Design for scale
- Document clearly
I value depth over shortcuts and real systems over tutorials.
- Java (Collections internals, concurrency, memory behavior)
- Spring Boot (Security, JWT, Refresh Tokens, Filters, Interceptors)
- REST API design (validation, error handling, versioning)
- Authentication & Authorization (roles, authorities, DB-backed identity)
- Rate limiting & production hardening
- Clean architecture & layering
- SQL & relational modeling
- JPA / Hibernate
- Indexing & performance considerations
- Transaction boundaries
- Python fundamentals
- Data processing mindset
- Preparing for ML model integration into backend services
A production-style backend project covering:
- Token-based rate limiting
- JWT authentication with refresh token rotation
- Role & authority-based authorization
- Database-backed identity
- Production hardening (CORS, CSRF awareness, security headers)
- System design trade-offs
👉 Repository:
https://github.com/JohnSunny21/AIEngineerJourney
This is not a tutorial repo.
It’s a daily engineering log with real systems thinking.
- Advanced backend system design
- Security-heavy architectures
- Database performance & scalability
- AI integration into backend services
- GitHub: https://github.com/JohnSunny21
- LinkedIn: LinkedIn
- Email: Email
⭐ If you find my work interesting, feel free to explore my repositories.