Marian St

Enhanced Observability: Improved logging and traceability across the distributed system to enable better debugging, audit trails, and compliance reporting for healthcare operations Message Center Microservice: Built a dedicated messaging microservice to handle inter-service communication, notifications, and potentially patient-provider messaging within the EMR ecosystem Maintained and enhanced existing EMR functionality while implementing FHIR standards Developed CI/CD pipeline reducing deployment time by 80% and achieved 70% code coverage across 15+ microservices Optimized PostgreSQL queries improving database performance for some of the queries by 300%

A resilient financial trading platform focused on compliance and security, featuring real-time transaction processing with advanced anti-money laundering, terrorist financing, and fraud detection capabilities. Built as a microservices architecture using Golang with robust failover mechanisms to ensure continuous operation during payment provider outages.

Activities and Responsibilities: Advanced Compliance Systems: Enhanced AML/fraud detection algorithms processing 50K+ daily transactions with <100ms response time Resilience & Outage Management: Implemented "outage mode" functionality that allows the platform to continue operating when payment providers are unavailable, likely including transaction queuing, fallback payment routes, and graceful degradation System Reliability: Designed fault-tolerant microservices architecture to ensure trading operations remain stable during external service disruptions Achieved 90% code coverage through comprehensive unit testing Built real-time transaction processing capabilities with Kafka and Redis Additional Technical Leadership: Designed microservices architectures across multiple projects Implemented CI/CD pipelines and automated testing strategies Migrated legacy systems to modern technology stacks Integrated multiple external APIs and payment providers across different domains

Developed e-commerce solution as a Senior full stack using PHP 7.4, MySQL, Zend Framework/Zend Express, MongoDB, Firebase, Docker, Apollo GraphQL, NestJS, NodeJS, VueJS; Implemented API Gateway over monolith with idea to split it in microservices; Migrated from PHP 5+ to PHP 7+; Integrated external payment providers; Product import/export.