Денис

Denys Mamchura
Java Backend Developer
Summary
Computer Science student experienced in Java 21 and
Spring Boot 3. Built a 7-service event-driven microservice
platform (Kafka, JWT/OAuth2, PostGIS, GCS) and a VPN
Contact management system with Stripe integration. Skilled in
CI/CD, Docker, and agile teamwork.
Phone
[open contact info](look above in the "contact info" section)
Project Experience
Email
[open contact info](look above in the "contact info" section)
City Pulse | Java, Spring Boot, PostgreSQL, Kafka,
Address
Lublin, Poland
Docker (Mar 2026 - Present)
Social platform for city events — 7 microservices in a
monorepo. Team of 3.
Expertise
• Architected a 7-service microservice backend with API
• Java 21, Spring Boot 3 Gateway, BFF aggregation layer, and event-driven
• Spring Cloud, Spring Security communication via Apache Kafka
• Spring Data JPA, WebFlux
• Implemented JWT/OAuth2 authentication (RSA signing,
• REST API, OpenAPI / Swagger
JWKS, Google OAuth2) and geospatial queries with PostGIS
• Apache Kafka
• PostgreSQL, PostGIS
• Built a pluggable cloud storage service (GCS / MinIO) and
• Flyway, Hibernate Spatial
managed DB versioning with Flyway
• Google Cloud Storage, MinIO • Automated CI/CD with 8 GitHub Actions pipelines:
• Docker, Docker Compose reusable workflows, multi-arch Docker builds (Buildx), and
• GitHub Actions (CI/CD) Docker Hub publishing
• JWT, OAuth2 (Google)
• Stripe API, Maven, Git
VPN System | Java, Spring Boot, PostgreSQL, Stripe
API (Oct 2025 - Jan 2026)
Language
Diploma project — monolithic backend for VPN subscription
Ukrainian (Native) management.
English (B1+) • Integrated Stripe API for subscription billing, payment
Polish (C1) processing, and webhook event handling
• Developed a REST API with user authentication, role-based
Links access control, and VPN server routing endpoints

GitHub (denys1204)
LinkedIn (denys-mamchura) Education
Maria Curie-Skłodowska University (UMCS) | Lublin, Poland
Bachelor's Degree in Computer Science Oct 2023 – Jul 2026
(Expected)