Oleg E.
Mid-Level Backend Engineer
Open to offersNew to PlatformAbout
Oleg E. is an experienced AI Engineer based in Belgrade, Serbia, specializing in the development of LLM-powered applications and backend distributed systems. With over four years of experience, Oleg has played a pivotal role in crafting agentic workflows, intent classification, and information-extraction pipelines integrated into backend services. His expertise in Python and Go enables a full lifecycle of product development from architecture through CI/CD and observability, ensuring reliability and structured outputs. His work on the Endo AI Assistant illustrates his ability to convert doctor's free-form notes into structured reports using Pydantic-AI agents and multi-axis evaluation harnesses. Throughout his career, Oleg has contributed to diverse industries, including robotics, warehouse automation, mobility SaaS, sportsbook platforms, and e-commerce. He has a track record of reducing system downtimes, optimizing query performance, and implementing observability with tools like Prometheus, Grafana, and OpenTelemetry, all while maintaining stringent data security standards.
Experience
Backend Engineer
ygrix · 2026 — 2026Designed a scheduler that is aware of time zones for managing long-running background jobs, which eliminated the need for manual intervention and decreased incidents during off-hours.Platform / Backend Infrastructure Engineer
NTLS · 2025 — 2026Established the production infrastructure from the ground up for a warehouse robotics platform, achieving stable uptime in the initial quarter. Instrumented multiple microservices with OpenTelemetry for improved distributed tracing, significantly reducing the mean time to diagnose issues. Designed CI pipelines in GitLab that included parallel testing stages to enhance build processes, leading to more frequent releases. Provisioned infrastructure across multiple cloud environments using Terraform, greatly shortening the environment spin-up time. Implemented structured logging alongside Grafana alerting, which helped minimize on-call distractions through effective signal-to-noise tuning.Backend Engineer
Confidential · 2024 — 2025Architected a multi-tenant backend that served over 30 enterprise clients, utilizing Row-Level Security in PostgreSQL for data isolation. Integrated Stripe billing while ensuring idempotent processing of webhooks, with no duplicate charges reported during six months of operation. Developed internal gRPC services to manage subscription lifecycle events, resulting in greater throughput than previous REST services. Enhanced the activation process for new tenants by implementing asynchronous provisioning, reducing the time from approximately two hours to under ten minutes.Backend Engineer
Confidential · 2023 — 2024Developed Go microservices, employing both REST and gRPC for essential betting workflows on a high-traffic platform. Improved the performance of critical queries in PostgreSQL through optimization techniques that decreased P99 latency significantly. Created asynchronous event pipelines using Kafka to manage bet settlements and odds updates, ensuring ordered processing for users. Established a complete observability stack with Prometheus, Grafana, and Alertmanager to lower the mean time to diagnose issues.Backend Engineer
Confidential · 2022 — 2023Constructed a microservice architecture incorporating catalog, cart, orders, and payments, enabled with horizontal auto-scaling in Kubernetes. Integrated various payment providers, ensuring that webhook handling was idempotent, maintaining a payment reconciliation error rate below 0.1%. Optimized PostgreSQL performance through advanced query techniques, connection pooling, and partitioning for order history. Transitioned from synchronous to asynchronous order processing with RabbitMQ, leading to better API response times during peak loads.