Олег

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Oleh Olshanskyi
Lodz, Lodz Voivodeship, Poland [відкрити контакти](див. вище в блоці «контактна інформація»)
[відкрити контакти](див. вище в блоці «контактна інформація») https://t.me/nelit_dev
Fullstack Software Engineer https://github.com/NELIT2714

SUMMARY
After more than two years as a full-stack developer, I’ve focused on building scalable, high-performance systems using Java and
the Spring Boot ecosystem. I work daily with tools like Spring Security, Spring Data JPA, and REST APIs, always aiming for clean,
maintainable code and robust backend architecture.
SKILLS
Technologies: Java (Maven, Gradle, Spring Boot, Hibernate, Spring Data JPA, Websockets, Spring Security etc), JavaScript (+ TS),
TailwindCSS, Axios, Svelte (SvelteKit), JWT, Redis, GitHub Actions, SQL/No SQL Databases, Python (FastAPI, Django, Flask, Aiogram), etc

OS: Ubuntu, Windows (Server), Debian, etc.

Tools: Postman, Swagger, Docker, Docker-Compose.

EDUCATION
Geodetic-Technical School Complex, Łódź | 2022 - Present

Languages
English (A2), Ukrainian (Native), Russian (Bilingual), Polish (B1).

EXPERIENCE
Fullstack Web Developer | DBA Agency | 2024-07 / 2025-04 | Team size: 6 people
Worked on a variety of projects for an outsourcing agency. Key responsibilities included:
Frontend Development:
Designed and developed user interfaces in Svelte + SvelteKit.

Successfully contributed to two projects simultaneously, effectively working with both Svelte teams. Stepped in during
managers' absences or technical issues to present the project to clients, address their queries,

and seamlessly integrate their requirements.
Backend Development:
Designed and implemented scalable REST APIs in Java

Built a secure and efficient payment service with T-Pay as the payment provider.

Developed various authentication systems, including custom solutions and integrations like Google Authentication.

Created workers with Redis, like an email processing worker to offload backend tasks and improve performance.

Mentored junior team members, guiding them on tools like Docker, workflows, and best practices for solving complex problems.

Fullstack Web Developer | Fame | 2025-04 / Present | Team size: 20+ people
Currently working on multiple high-impact projects for an outsourcing agency. Key responsibilities:

Frontend Development:
Leading frontend development using Svelte + SvelteKit, delivering full website interfaces from concept to deployment.

Built complete user-facing applications, handling dynamic content, animations, internationalization, and accessibility.

Collaborated with designers and backend teams to ensure seamless UI/UX and integration.
Backend Development:
Designed and implemented scalable REST APIs in Java

Continued work on payment integration services using Java, supporting gateways like RozetkaPay, Cryptomus, and
Betatransfer.

Maintained and improved the support agent system, including real-time communication over WebSockets and bot
integration.

Focused on high performance, stability, and clean architecture in microservice-style components.

Mentoring new hires and contributing to knowledge-sharing within the backend department.

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