Oleksandr Rohoza

• Designed and implemented robust RESTful APIs using both Spring Boot and Node.js, aligned with best practices for cloud-native and microservices architecture. • Developed secure and scalable business logic services integrated with PostgreSQL, including advanced data modeling, indexing, and SQL performance optimization. • Optimized backend services for distributed deployment in AWS, ensuring high availability, low-latency response times, and resource efficiency. • Created and maintained unit and integration tests for API endpoints, service logic, and database interactions using JUnit, Jest, and Postman. • Collaborated closely with the Full-Stack Lead to define technical standards, identify bottlenecks, and ensure alignment with architectural goals. • Contributed to technical documentation covering API specifications, service flows, and architectural decisions to facilitate collaboration and maintainability. • Followed CI/CD pipelines using GitHub Actions and GitLab CI to automate testing and deployments. • Applied web security best practices such as input validation, token-based authentication, and API rate limiting. • Built containerized services with Docker and assisted with AWS orchestration strategies for scaling backend workloads (e.g., ECS, Fargate).

• Designed and built cloud-native backend services using Python (FastAPI), following modular architecture and REST/GraphQL API specifications. • Developed high-performance GraphQL endpoints for client-facing applications, enabling flexible data access and reducing over-fetching. • Containerized microservices using Docker, ensuring consistency across development and production environments. • Deployed and managed services on AWS, leveraging Lambda, API Gateway, ECS, and S3 for scalable infrastructure. • Collaborated closely with frontend teams to define GraphQL schemas, resolve nested queries, and improve client-server interaction. • Wrote comprehensive unit and integration tests with pytest and Postman, integrated into GitHub Actions for continuous delivery. • Monitored service health using AWS CloudWatch and set up structured logging for debugging and observability. • Participated in system design discussions to ensure optimal API performance and integration across distributed components.

• Assisted in developing and maintaining backend features using PHP and the Symfony framework, contributing to high-traffic web applications. • Built reusable Symfony services and controller logic, following PSR standards and clean code practices. • Integrated RESTful APIs with frontend applications and participated in bug fixing, feature updates, and version upgrades. • Worked with Doctrine ORM for entity modeling and relational database access, primarily using MySQL. • Wrote unit and functional tests using PHPUnit and Symfony’s testing utilities to ensure application stability. • Collaborated with senior developers through code reviews and daily stand-ups to improve feature delivery and team alignment. • Used Git for version control and participated in team-based workflows using GitLab and Jira. Gained exposure to API security, form handling, validation, and Symfony profiler/debugging tools.