Experience
- Onboarded into an existing distributed system, analyzed architecture and service dependencies
- Designed and developed the billing subsystem (billing / billing-lite) for payment processing and accounting
- Integrated a payment provider into the microservices architecture
- Designed inter-service interaction contracts via API Gateway
- Set up a local development and testing environment (PostgreSQL, Kafka, Redis, S3-compatible storage)
- Collaborated with DevOps on dev/test environments and documented service startup sequences
- Developed the backend part of the billing-lite service and integrations with user-service
- Analyzed and resolved integration and infrastructure-related issues during development
Project stack: Go, Python, PostgreSQL, Redis, Apache Kafka, Kubernetes, GitLab CI/CD
- Participated in stabilizing the microservices architecture after partial migration from a monolith
- Analyzed and resolved issues related to high coupling between services
- Worked with Kafka and asynchronous inter-service communication
- Maintained and evolved REST APIs in a distributed system
- Operated geospatial components (PostGIS, GeoServer)
Project stack: Java 17/21, Spring, Gradle, PostgreSQL, Apache Kafka, Flyway, GitLab, Swagger, Postman, PostGIS, GeoServer
- Worked with a legacy monolithic codebase without documentation or onboarding
- Performed a full refactoring and redesign of the system to meet new requirements
- Designed and developed REST APIs
- Managed database schema using PostgreSQL and Flyway
- Implemented cross-cutting audit logging using Spring AOP
- Integrated object storage (MinIO / S3-compatible)
- Worked with geospatial data (PostGIS)
Project stack: Java 17, Spring Framework 3.2.4, Gradle, PostgreSQL 15.2, Flyway, Docker, GitLab, Swagger, Postman, Apache POI, MinIO, PostGIS
- Designed a backend service for automating high-frequency requests
- Implemented an adaptive polling mechanism considering external API limits
- Developed a Telegram bot as the main user interface
- Automated task selection by type, area, and radius
- Worked with geolocation and radius-based search
- Isolated user sessions using individual proxies
- Optimized request frequency to reduce load
Project stack: Java 21, Spring Boot 3, Gradle, PostgreSQL, PostGIS, Spring Data JPA (Hibernate), Flyway, Apache HttpClient, Jackson, Telegram Bot API, S2 Geometry, MapStruct, Lombok
- Designed and developed a POS system from scratch
- Implemented inventory management and sales workflow
- Developed a desktop UI using JavaFX
- Implemented an offline-first approach using SQLite
- Configured synchronization between local data and central MySQL database
- Maintained and supported the system after deployment
Project stack: Java 17, Hibernate, MySQL, SQLite, JavaFX, JDBC