Contact information

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Work experience

Java developer

from 09.2025 to now (11 months)
winwin.travel, Дистанційно (IT)

Навчився роботи у команді та зрозумів повний цикл розробки продукту. Ну і звичайно зробив скачок по навичках зі звичайний CRUD після курсів до використання реальних методів розробки.

Education

Національний Лісотехнічний Університет

Інженерія Програмного Забезпечення
Unfinished higher, from 2023 to 2027 (4 years)

Knowledge and skills

• Доброзичливість
• Відповідальність
• Пунктуальність
• Git
• Java
• Spring Boot
• GitHub
• Hibernate
• IntelliJ IDEA
• MySQL
• Уважність
• Знання принципів ООП
• Java Core
• REST API
• Docker
• SQL
• NoSQL
• Open

Language proficiencies

English — average

Additional information

Roman Luchko

Lviv, Ukraine | Open to remote work and relocation
[open contact info](look above in the "contact info" section) | [open contact info](look above in the "contact info" section)

https://www.linkedin.com/feed/ | https://github.com/romander333

Summary

Java Developer with backend development experience in a product-based startup. Working with Java and Spring Boot, with a focus on database-heavy logic, modularization, refactoring, third-party API integrations, and optimization of AI-driven processing flows. Practical experience with PostgreSQL, MongoDB, Hibernate, Liquibase, and REST APIs.

Technical Skills

Programming Language: Java 17/21
Frameworks and Libraries: Spring Boot, Spring Web, Spring Data JPA, Spring Security, Hibernate, MapStruct
Databases: PostgreSQL, MongoDB
Persistence and Migrations: JPA, Liquibase
APIs and Integrations: REST APIs, third-party API integrations, OpenAI API
Tools: Docker, Maven, Gradle, Git
Architecture and Practices: OOP, SOLID, Design Patterns, Modular Monolith
Languages: English — Intermediate, Ukrainian — Native

Work Experience
Java Developer

WinWin.travel | Remote
September 2025 – Present

Split a large database-heavy module into 7 specialized submodules, and the application layer into 4 separate modules with clear responsibilities, reducing coupling between components and simplifying maintenance.
Participated in refactoring large modules and complex parts of the codebase by breaking down large classes and methods into smaller components using Strategy and Factory patterns.
Helped reduce a MongoDB-based history logging service from approximately 700 to 300 lines of code by separating responsibilities and simplifying further maintenance.
Reworked processing for 10+ OpenAI assistants into a status-driven step-by-step pipeline with persisted processing state, allowing the system to resume after failures without rerunning all stages.
Implemented reuse of previously stored results from history/MongoDB to avoid unnecessary repeated OpenAI calls, reduce token costs, and shorten reprocessing time after crashes or system hangs.
Implemented in-memory caching for assistant configuration, reducing database access from approximately 7 queries per processing flow to 1 initial query, followed by in-memory reads.
Migrated identifiers from Long to UUID across 16 database tables using Liquibase, updated Hibernate relationships, and preserved data integrity during the transition.
Optimized PostgreSQL usage by writing custom queries, resolving N+1 query issues, improving collection handling in performance-sensitive areas, and working with database-heavy business logic.
Developed a separate email validation service through a third-party API integration, improving the reliability of the email flow.

Education
Ukrainian National Forestry University of Ukraine, Lviv

Bachelor’s Degree in Software Engineering
Expected graduation: 2027

Mate Academy
Java Development Course