Tomris Teymurlu

Improved product authentication and reliability by delivering 6 core backend modules (authentication, password recovery, and category management) using Spring Security and Keycloak, reducing login-related user errors by 40% and stabilizing session flow across services. Supported product scalability by delivering 10+ REST APIs for order management and user services, enabling 100+ daily transactions with 99% success. Contributed to 3 production releases in an Agile team.

Designed and implemented a QR classification engine for a payment processing system; developed rule-based detection logic integrated with Oracle PL/SQL packages; built scheduled background processing with Spring TaskScheduler; integrated Java backend with Oracle stored procedures (SimpleJdbcCall, REF_CURSOR); implemented geo-based validation and rule-driven payment classification for high-availability financial transactions.

Built a scalable delivery platform foundation by implementing 40% of the core domain logic for a microservice-based delivery system using DDD and Hexagonal Architecture. Refactored backend to decouple business logic from infrastructure, increasing deployment frequency and maintainability. Optimized cross-service communication with RPC, CLI listeners, and TCP-based messaging, reducing average request latency and improving reliability. Automated API configuration via reusable templates and centralized registries to accelerate onboarding and feature rollout.