Andrii Kononenko
Senior Java / Full-Stack Developer

I build scalable backend systems and real-time web applications.

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Projects

Proof of work — what you can click and try.

Low Five — online card game

Real-time multiplayer web game. WebSockets (STOMP), Java backend, React/TS frontend, sessions, stats, matchmaking.

  • Lobby system, reconnect handling, real-time game events
  • Dockerized deployment, Cloudflare/Caddy setup
  • Responsive UI for desktop and mobile
Play Original game

Developer tools & experiments

Small utilities, prototypes and technical deep dives: performance tuning, data processing, leetcode challenges.

  • Reusable React components & patterns
  • Backend utilities for data handling
  • Infrastructure automation
GitHub

Stack

The tools I use most often.

Backend

Java Spring Boot Hibernate Microservices Kafka REST WebSockets

Frontend

React TypeScript JavaScript Redux HTML CSS SCSS

Database

PostgreSQL MySQL Elasticsearch Redis Cassandra MongoDB

Infrastructure

Docker Linux Git Cloudflare Caddy AWS GCP CI/CD ELK

About

Short, practical summary.

I’m a senior software engineer focused on backend architecture and real-time applications. I enjoy designing clear APIs, reliable distributed workflows, and performance-minded data layers. Outside of work, I build side projects and polish them to production quality.

Contact

Best way to reach me.

Email: andriikononenko17@gmail.com

GitHub LinkedIn Low Five

Prefer a short message: what you’re building, what role, and your timeline — I’ll reply faster 🙂