Roman – Golang, Kubernetes, Redis

A telemedicine platform supporting healthcare services through digital workflows and online transactions. The engineering work focused on developing production backend systems, improving the reliability and consistency of business-critical operations, and optimizing application performance. The platform includes distributed services, compliance-sensitive business logic, and AI-powered automation capabilities.

• Architected and led backend development of a greenfield product from initial design to production, hiring and mentoring a team of four engineers;
• Extracted a compliance-sensitive rule engine from a monolithic application into a dedicated service, resolving inconsistent rule execution and recurring production incidents;
• Implemented distributed locking and Redis pub/sub-based cache invalidation across services, eliminating race conditions in concurrent user workflows and reducing cache staleness from approximately 10 seconds to under one second;
• Optimized PostgreSQL queries on checkout-critical endpoints by eliminating N+1 queries and introducing composite indexes, reducing p95 latency from approximately 800 ms to 45 ms;
• Introduced distributed tracing using OpenTelemetry and Jaeger across services, reducing mean time to recovery for critical production incidents by approximately 30%;
• Developed LLM-powered support automation and integrated an AI code review agent into CI/CD workflows, reducing external tooling costs by approximately 90%.

A real-time messaging platform enabling businesses to communicate with customers through integrated messaging channels, including WhatsApp. The solution supports enterprise messaging workflows, third-party API integrations, asynchronous message processing, and AI-powered customer support automation, with a focus on reliable message delivery and scalable backend services.

• Joined as an early engineering team member, contributing to system architecture, key technical decisions, and mentoring other engineers;
• Designed and implemented a WhatsApp integration that supported the company's official Meta partnership and enabled onboarding of five enterprise clients at launch;
• Engineered a two-tier retry mechanism with exponential backoff, a slow queue, and circuit breaker patterns to handle unreliable third-party APIs, reducing data loss from approximately 6% to below 0.4%;
• Implemented Redis-based distributed locking and asynchronous webhook processing, reducing duplicate message delivery from approximately 2% to below 0.05% while maintaining a 99.9% delivery rate during traffic spikes;
• Developed content-based media deduplication across external integrations, reducing AWS S3 storage costs by approximately 25%;
• Built AI-powered automation tools for enterprise clients, reducing customer support response times by approximately 40%.

A payment processing platform supporting two large-scale consumer dating applications with a combined user base of over 70 million. The system handles payment transactions and event processing, with a focus on security, reliability, data consistency, and performance. The engineering work included developing backend services, improving transaction processing, and implementing security measures to support PCI DSS certification.

• Developed backend services and a vulnerability scanning pipeline for a payment system supporting applications with over 70 million users, contributing to PCI DSS certification;
• Implemented a two-level caching architecture using in-memory caching and Redis, reducing p95 response latency from 180 ms to 35 ms;
• Designed and implemented a Kafka-based payment event processing layer with idempotent producers and a transactional API, achieving zero duplicate events across more than 100 million processed events;
• Built a ClickHouse-based analytics pipeline for processing transactional data;
• Mentored junior engineers and contributed to improving backend engineering practices across the team.

Backend software development for multiple international clients across healthcare, genomics, indoor navigation, and investment analytics. The projects included a healthcare staffing platform with real-time shift matching, an indoor navigation solution using graph-based routing algorithms, a genomics platform, and an investment analytics system. The work focused on backend service development, algorithm implementation, application performance, and maintaining reliable delivery across multiple projects.

• Led backend development of a healthcare staffing platform, implementing real-time shift matching and alerting services in a HIPAA-regulated environment;
• Designed and implemented an indoor navigation solution using graph-based routing with Dijkstra's algorithm and trigonometric calculations for directional guidance;
• Developed features and delivered performance improvements for a genomics platform;
• Built backend services for an investment analytics platform;
• Took ownership of five concurrent client projects following the closure of another development office, maintaining delivery continuity without service disruptions.