Александр Ярощук

Full-Stack Developer with a strong focus on Backend development using the Node.js ecosystem (NestJS, Express, TypeScript). Experienced in designing scalable REST & GraphQL APIs, optimizing database performance (PostgreSQL, MongoDB), and establishing production-ready CI/CD pipelines.

Junior Backend Developer

(2026-04)

Note: Project details are under NDA. Developed core backend services and optimized existing infrastructure for web applications.

• Built and deployed new REST API endpoints from scratch, transforming functional requirements into clean and scalable backend logic.
• Managed database structures and wrote queries with multiple table joins using TypeORM for complex data aggregation.
• Integrated Redis caching for high-load API endpoints to minimize database queries and accelerate response times.

QuizHub

• Engineered a modular multi-tenant subsystem allowing corporate owners to manage permissions, issue invites, and control user roles (Owner, Admin, Member).
• Integrated Redis caching for active submissions (48h expiration), cutting primary PostgreSQL load during high-traffic testing peaks.
• Developed a live notification system via SSE, automated daily re-engagement cron-jobs, and built high-volume JSON/CSV data export with Excel parsing.
• Containerized infrastructure via Docker Compose and set up CI/CD via GitHub Actions to AWS.

ChatApp

• Implemented a system of personal and group real-time chats on WebSockets, adding support for P2P audio and video communication via WebRTC.
• Transitioned key communication features to GraphQL (Apollo Server), preventing data over-fetching and decreasing payload size.
• Enforced secure authentication flow utilizing JWT tokens stored via httpOnly cookies with dynamic user access verification.

Bachelor - Software Engineering - State University of Intellectual Technologies and Telecommunications (2023-09 - 2025-06)

Junior Specialist (Junior Bachelor) - Computer Engineering - Odesa Vocational College of Computer Technologies (2019-09 - 2023-06)