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Java Backend developer with 1.5+ years of experience and a strong focus on building REST APIs, authentication, and database-backed services. Skilled in Spring Boot, Hibernate, JWT/OAuth, and testing practices to deliver stable, performant backend systems. Quick learner with an analytical mindset and team-oriented approach. Experienced with PostgreSQL/MySQL/H2, Liquibase, Docker, Git/Jira/Scrum, and CI-style workflows to support real-world product development and continuous improvement.…Java Backend developer with 1.5+ years of experience and a strong focus on building REST APIs, authentication, and database-backed services. Skilled in Spring Boot, Hibernate, JWT/OAuth, and testing practices to deliver stable, performant backend systems. Quick learner with an analytical mindset and team-oriented approach. Experienced with PostgreSQL/MySQL/H2, Liquibase, Docker, Git/Jira/Scrum, and CI-style workflows to support real-world product development and continuous improvement.

Serhii

Back-End Developer, Web Developer, Programmer, +2

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Java Backend developer with 1.5+ years of experience and a strong focus on building REST APIs, authentication, and database-backed services. Skilled in Spring Boot, Hibernate, JWT/OAuth, and testing practices to deliver stable, performant backend systems. Quick learner with an analytical mindset and team-oriented approach. Experienced with PostgreSQL/MySQL/H2, Liquibase, Docker, Git/Jira/Scrum, and CI-style workflows to support real-world product development and continuous improvement.…Java Backend developer with 1.5+ years of experience and a strong focus on building REST APIs, authentication, and database-backed services. Skilled in Spring Boot, Hibernate, JWT/OAuth, and testing practices to deliver stable, performant backend systems. Quick learner with an analytical mindset and team-oriented approach. Experienced with PostgreSQL/MySQL/H2, Liquibase, Docker, Git/Jira/Scrum, and CI-style workflows to support real-world product development and continuous improvement.

Available to hire

Java Backend developer with 1.5+ years of experience and a strong focus on building REST APIs, authentication, and database-backed services. Skilled in Spring Boot, Hibernate, JWT/OAuth, and testing practices to deliver stable, performant backend systems.

Quick learner with an analytical mindset and team-oriented approach. Experienced with PostgreSQL/MySQL/H2, Liquibase, Docker, Git/Jira/Scrum, and CI-style workflows to support real-world product development and continuous improvement.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Language

German

Fluent

Ukrainian

Advanced

Russian

Advanced

Work Experience

Java Backend Developer at InnterTood GMbH (Lewes Delaware USA)

January 1, 2024 - January 1, 2025

Backend development using Java with Spring Boot and Hibernate, building RESTful APIs and integrating security (JWT/OAuth). Implemented unit and integration tests (JUnit, Mockito) and worked with relational databases (MySQL, H2) plus Liquibase for schema management. Containerized services with Docker and collaborated in an agile Scrum team for feature delivery and defect fixes.

Java Backend Developer Intern at Start Institute by TelRan

January 1, 2024 - December 31, 2025

Hands-on backend development using Java, Spring, and related technologies; participated in API design, testing, and deployment.

Java Backend Developer Intern at Starta Institute by TelRAn (Berlin, Germany)

January 1, 2023 - January 1, 2024

Developed a reactive backend using Spring WebFlux for efficient data processing and implemented Firebase authentication and real-time database integration for monitoring and user-related updates. Worked with PostgreSQL and Liquibase to manage database migrations and queries. Ensured performance and stability via continuous testing and code reviews.

Java Web Developer Intern at Start Institute by TelRan

January 1, 2023 - December 31, 2024

Contributed to Java-based web projects, building REST APIs with Spring and integrating with databases; gained experience in modern development workflows and testing.

System Administrator at Ferrum AG (Kryvyi Rih, Ukraine)

January 1, 2015 - January 1, 2020

Developed backend features in Java for a gaming-related application (reactive backend with Spring WebFlux). Implemented Firebase-based authentication, real-time data handling, and used PostgreSQL plus Liquibase for database management. Participated in an agile Scrum team, performed testing and code reviews, and supported reliable IT operations with monitoring tools.

System Administrator at Ferrum AG

January 1, 2015 - December 31, 2020

Developed endpoints to control game character behavior in a gaming application; implemented a reactive backend with Spring Web Flux; used Firebase Authentication; managed real-time data with PostgreSQL and Liquibase; Docker-based deployment; Linux administration.

Java Web Developer at Starta Institute by TelRAn (Berlin, Germany)

January 1, 2003 - January 1, 2009

Web development experience focused on building backend services with Java, Spring, and Spring Boot, and providing secure APIs using JWT authentication. Container/configuration work with Docker and building reliability through unit and integration tests; supported stable IT operation through server/network configuration and monitoring.