Mobile app, ‘Payments and Transfers’ domain- Transition from legacy systems: conducted an in-depth analysis of the current legacy implementation, considering code, insights from colleagues, and available fragments of documentation. Documented the functionality / logic and prepared recommendations for migration to the target implementation.- New feature development: refined business requirements, made architectural diagrams, sought alignment with architects, and, based on the agreed architecture, prepared requirements for the implementation of new services and modifications to existing ones.- Contributed to the refinement of ABS (core bank system), card and emoney processing, enterprise service bus.- Created component diagrams and defined service/method requirements through sequence diagrams and textual descriptions, created database schemas when necessary.- Maintained documentation within my area of responsibility.Tools: Confluence, Jira, IDEA, draw.io, Postman, SOAP UI, DBeaverTechnologies: Backend - REST, SOAP, Kafka, IBM MQ, Database - PostgreSQL

Mobile application for remote vehicle management and a back-office system for managing vehicle fleets and users. Technology startup- In collaboration with POs and Tech Leads outlined business processes to be automated, covering both the current state (AS IS) and the desired future state (TO BE), as a result created activity diagrams primarily using draw.io and Miro.- Prepared architectural proposals for the team, including data schemas (ERD), descriptions of operational logic and integrations (activity and sequence diagrams), input/output parameters (JSON, GraphQL), and enhancements to existing services.- For web and mobile clients participated in creating mockups with designers and POs to address corner cases, error handling, necessary parameters, and to prepare task descriptions for API changes. This involved providing comments in Figma and, for complex cases, separate documentation in Confluence.- Maintained documentation for implemented features, including ERDs, component diagrams, and descriptions of technical solutions, using Confluence and plantuml.- Prepared task descriptions and requirements for the upcoming sprints in Jira and Confluence.- Developed use cases, user stories, and functional requirements for my features to facilitate integration with other teams responsible for hardware implementation.Tools: Confluence, Jira, IDEA, DataGrip, draw.io, Postman, GraphQL ExplorerTechnologies: Backend for Frontend (BFF) - GraphQL, backend - REST, Kafka, Database - PostgreSQL

Media planning and management systemInternal project, SCRUMBusiness and functional requirements (Confluence)Handle backlog tasks (Jira)Requirements for external data connections (REST/SOAP, Postman, SOAP UI)Data modeling (ER, Oracle Data Modeler)Testing (manual, Selenium)