Work Experience
Java Backend Developer - Group 107 (MPCheck)
Duration: Apr 2023 – Present
Summary:- MPCheck is a healthcare platform focused on patient management, scheduling, and secure medical document handling
- The platform leverages modern Java technologies and cloud services to deliver scalable and secure healthcare solutions
Responsibilities:- Architected core backend services using Spring Boot 3.5 and Hexagonal Architecture ensuring clean separation of layers.
- Designed and implemented RESTful APIs for patient management, scheduling, and authentication workflows.
- Integrated AWS S3 presigned URLs for secure medical document handling, reducing upload latency and improving user experience.
- Implemented JWT-based authentication with token refresh and integrated SendGrid and Twilio for transactional notifications.
- Delivered a multi-region configuration system for dynamic regional adaptation at runtime.
- Optimized PostgreSQL queries and schema design to reduce average API response time.
- Collaborated with frontend and DevOps teams on OpenAPI documentation and CI/CD pipelines.
Technologies: Java 22, Spring Boot 3.5, Spring Security, JPA/Hibernate, PostgreSQL, Liquibase, AWS S3, Docker, MapStruct
Java Backend Developer - Group 107 (ENSO)
Duration: Aug 2021 – Mar 2023
Summary: ENSO is an all-in-one SMB Super App providing various backend modules to support small and medium business operations, integrating multiple third-party services for payments, project management, and e-commerce.
Responsibilities:- Built microservice-based backend modules using Spring Boot 2.7 and clean architecture principles.
- Designed and optimized RESTful APIs integrating Stripe, Monday.com, Amazon SP API, and AWS services.
- Implemented secure authentication and authorization using JWT and Spring Security with token lifecycle management.
- Managed database migrations with Liquibase and optimized PostgreSQL queries for performance-critical flows.
- Maintained code quality using Jacoco, Mockito, JUnit 5, and Checkstyle.
Technologies: Java 17, Spring Boot 2.7, PostgreSQL, AWS (S3, ECS), Stripe API, Liquibase, Docker
Software Engineer - Vakoms (customer: Taboola) (Taboola Real-Time Data Pipeline)
Duration: Nov 2019 – Jul 2021
Summary: Taboola operates one of the world's largest real-time big data pipelines, processing over 20 TB of data daily to deliver personalized content recommendations to over 1 billion unique visitors monthly.
Responsibilities:- Developed and maintained backend services for Internet Personalization, Content Feed, and Real-Time Bidding systems.
- Worked with high-throughput distributed systems using Kafka, Apache Spark, Hadoop, Cassandra, and Vertica.
Technologies: Java, Kafka, Spark, Hadoop, Cassandra, Vertica, MySQL, HDFS, BigQuery, Docker, Linux
Software Engineer - EPAM Systems (customer: SAP SE) (SAP Marketing Support Project)
Duration: Jul 2019 – Nov 2019
Summary: SAP Marketing support project involves enhancing and maintaining SAP's marketing software solutions to improve marketing automation and customer engagement.
Responsibilities:- Implemented new features and fixed bugs to enhance SAP Marketing support functionalities.
Technologies: Java 8, Spring Boot, Spring WebFlux, Spring Security, Groovy, Cucumber
Software Engineer - Conscensia (Danish Enterprise Projects)
Duration: Sep 2013 – Nov 2019
Summary: Worked on multiple Danish enterprise projects including a clinical information system deployed in Danish hospitals, a municipal integration platform, and a tax management platform, delivering full-cycle backend development.
Responsibilities:- Developed domain logic, REST/SOAP services, and database design.
- Performed unit and integration testing to ensure software quality.
Technologies: Java 8, Spring MVC, Spring Webflows, JPA/EJB, Oracle DB, JUnit, Mockito, Angular
Education
- M.Sc. Computer Science
Lviv Polytechnic National University
1995 – 2000
Upstaffer since April, 2026
