At EPAM Systems, I modernized six production applications from Java 8 to Java 25, upgrading Vaadin, Gradle, and Tomcat along the way. I also migrated their JUnit suites to JUnit 5 and optimized PostgreSQL reporting queries with expression indexes.
On EPAM Systems' payments projects, I implemented crypto payment flows and integrated Klarna and Plaid into an existing e-commerce payments ecosystem. I also contributed to Visa and Mastercard acquiring platforms, building REST endpoints, merchant configuration, and invoice and reporting features.
