Євгеній

Yevhenii Vynnyk

Middle Java Backend / Full-Stack Developer

Chernihiv, Ukraine
Email: [открыть контакты](см. выше в блоке «контактная информация»)
Phone: [открыть контакты](см. выше в блоке «контактная информация»)
Telegram: https://t.me/Evgen_Vynnyk
GitHub: https://github.com/VynnykYevheniy

Professional Summary

I am a Middle Java Backend Developer with more than three years of commercial experience
in backend development and additional hands-on experience in building mobile and web
applications. My primary expertise lies in developing RESTful backend services using Java and
Spring Boot, designing relational databases, and building scalable, maintainable system
architectures.

In addition to backend development, I have practical experience with frontend and mobile
technologies, which allows me to work effectively in a Full-Stack role. My professional
background also includes experience in IT support and system administration, giving me a
solid understanding of how software solutions operate in real enterprise environments.

Currently, I am actively developing my own pet project, Mate Gym — a fitness platform that
combines a backend service, a mobile application, and a web application. Within this project,
I apply architectural best practices, an offline-first approach, caching strategies, and full end-
to-end system integration.

Work Experience

Middle Java Developer — United Thinkers

May 2022 – April 2024 | Remote, Ukraine

At United Thinkers, I was involved in the development and maintenance of backend solutions
for web and e-commerce projects. My responsibilities covered the full backend development
lifecycle, from API design and implementation to performance optimization and production
support.

I worked extensively with Java and Spring Boot, developing and optimizing RESTful APIs with a
strong focus on scalability, security, and system stability. For database interaction, I used
Hibernate / JPA, designed ORM models, and optimized SQL queries.

The projects included both monolithic and microservices architectures. In microservices-
based systems, I participated in developing independent services, implementing inter-service
communication using RabbitMQ, and preparing services for deployment and scaling with
Kubernetes.
I used Liquibase to manage database schema changes and migrations. Team collaboration
and version control were handled using Git, following industry best practices.

A separate initiative I led was the development of an image processing service responsible for
image search, download, formatting, and storage, which significantly improved the flexibility
and performance of image-related functionality.

Junior Java Developer — WebSyndicate

March 2021 – April 2022 | Remote, Ukraine

At WebSyndicate, I worked on the development of a monolithic e-commerce platform. My
primary focus was backend development using Java and the Spring Framework.

I was responsible for writing clean, maintainable Java code and developing REST APIs that
enabled interaction between the server-side logic and the user interface. I used Spring Boot to
simplify application configuration and Spring Security to implement authentication and
authorization mechanisms.

For database access, I worked with Hibernate, which allowed efficient data management and
optimized interaction with relational databases. Team collaboration and version control were
carried out using Git.

Support Engineer

December 2024 – December 2025 | On-site, Ukraine

As a Support Engineer, I provided comprehensive IT support for enterprise users and ensured
the stable operation of workplace infrastructure.

My responsibilities included administering Microsoft Active Directory, managing users and
groups, configuring access rights, organizational units, and basic Group Policy settings. I also
diagnosed and resolved authentication and permission-related issues.

I performed basic network administration tasks, including troubleshooting LAN connectivity
issues, working with IP addressing, DHCP, and DNS, and identifying hardware-related network
failures.

In addition, I maintained and supported desktop computers, laptops, printers, and other
peripheral devices. This included installing, configuring, and restoring Windows operating
systems, as well as performing software updates and maintenance.

This role strengthened my understanding of enterprise infrastructure and the operational
aspects behind software systems.

Pet Project

Mate Gym — Fitness Platform
October 2024 – Present

Mate Gym is my personal full-stack pet project aimed at building a modern fitness platform
consisting of a backend service, a mobile application, and a web application.

The backend is implemented using Java and Spring Boot and exposes RESTful APIs for both
mobile and web clients. PostgreSQL is used as the primary database, while Redis is integrated
for caching and performance optimization. All APIs are documented using Swagger
(OpenAPI).

The mobile application is built with React Native and Expo and follows an offline-first
approach. Data is stored locally in SQLite and synchronized with the backend when network
connectivity is available.

The web application is developed using React, TypeScript, and Tailwind CSS. The interface is
responsive, component-based, and fully integrated with backend services.

This project allows me to practice full-cycle development, architectural decision-making, API
design, and the integration of multiple technologies into a cohesive system.

Technical Skills

Backend:
Java — Advanced
Spring Boot / Spring Framework — Advanced
RESTful API Design — Advanced
Hibernate / JPA — Advanced
PostgreSQL — Advanced
Redis — Intermediate
Swagger (OpenAPI) — Intermediate

Frontend / Mobile:
React — Intermediate
TypeScript — Intermediate
React Native — Intermediate
Expo — Intermediate
Tailwind CSS — Intermediate
SQLite — Intermediate

DevOps & Infrastructure:
Git — Advanced
Docker — Basic–Intermediate
Kubernetes — Basic
Microsoft Active Directory — Intermediate
Networking (LAN, DNS, DHCP) — Basic–Intermediate

Languages
English — B1