I was responsible for integrating 3rd-party payment service providers and communicating with the tech team. Besides, I participated in the main orchestrator refactoring, the implementation of new features, and improvements to the system's overall performance. Also, I mentored my colleague, the junior developer, practiced tdd with junit 5 and testcontainerss, maintained ci/cd pipelines via github actions on kubernetes/aws.

Stack: Kotlin, JDK 22, Spring Boot 3, WebFlux, Kotlin Coroutines, REST, gRPC, Saga Orchestration, Outbox, AWS, Prometheus, Grafana, Kubernetes, PostgreSQL, Redis, Kafka.

- Independently integrated 3 international payment service providers, implementing 3DS/non-3DSauthentication, QR-codes, Google Pay, and Apple Pay.

- Refactored payment integration architecture using the Strategy pattern, reducing implementation timefrom 2 weeks to 4 days (70% faster)

- Mentored junior developer through onboarding, daily code reviews, and architecture discussions,approving 10+ PRs monthly

- Optimized database performance by redesigning indexes for tables, reducing query latency by 65%

Worked at a startup company that was building plugins via the Cloudbeds RMS/PMS System. The main plugin was a SaaS platform - a hotel booking website builder.I participated in the architecture development and client (Hotel owners) communication. I was responsible for implementing CRUD operations for the system, integrating with the Cloudbeds API, conducting code reviews, and maintaining 80%+ test coverage for the services.

Stack: Java 21, Spring Boot, Virtual Threads, JPA, PostgreSQL, MongoDB, Redis, RabbitMQ, REST, gRPC, GCP, Prometheus, Grafana, CI/CD, GitHub Actions, Kubernetes.

- Engineered Cloudbeds API integration from scratch, enabling 200+ hotels to launch SEO-optimized booking websites, processing 2,000+ daily bookings

- Collaborated directly with international clients to accelerate decision-making and reduce delivery timesbottlenecks

- Conducted regular code reviews to improve code quality and system stability

- Develop front-end applications using React.js and Next.js for personal projects.

- Build a kotlin multiplatform application with jetpack compose including iOS, Android and Desktop platforms- Designed applications with saga patterns (both choreography and orchestration)

- Design applications with Transactional Outbox to guarantee at-least-once delivery and idempotent consumers to achieve exactly-once processing

- Deployed my own projects to cloud using docker, Kubernetes, GitHub actions, Jenkins, DigitalOcean, Google Cloud Platform

Worked as a volunteer in a student platform project for KPI University. I was responsible for converting schedule data from a table into a clean, well-structured JSON format, creating a REST API to fetch the schedule, fixing bugs, writing documentation, and supporting test coverage.

Stack: Java 17, Spring Boot, JPA, PostgreSQL, Redis, REST, CI/CD, Jenkins, DigitalOcean.

- Built a student-facing web platform adopted by 3,000+ students, reducing schedule conflicts andimproving course planning efficiency

- Automated course scheduling through a REST API scraping pipeline, eliminating 16 hours of manualwork weekly

- Maintained test coverage across all services using JUnit 5 and Mockito