Illia Stebelski

• • Provided technical leadership for a team of 5 backend engineers, covering architectural direction, code review, and mentorship.

• • Led the decomposition of a monolithic platform into independently deployable microservices, including the Surveys and Education modules, each extracted into a dedicated service.

• • Designed cross-microservice communication patterns, including Kafka-based event streaming and CQRS, to support reliable, independent service operation across a multi-tenant platform serving tens of thousands of users across many client organizations.

• • Operated services on Kubernetes and built out observability with Prometheus, Grafana, and OpenTelemetry.

• • Introduced the Repository Pattern and authored a refactoring roadmap to reduce coupling across legacy parts of the codebase.

• • Advocated for and implemented Clean Architecture, SOLID, and OOP conventions to improve long-term maintainability.

• • Built and operated 5 microservices for pharmacy stock, receipts, and financial reporting.

• • Drove a refactoring effort that reduced service processing time from 5 hours to 15 seconds.

• • Implemented a bulk table synchronizer for denormalized data records that preserves archived rows.

• • Redesigned the API testing framework around modern best practices, reducing technical debt and raising test coverage to 80%.

– Contributed to application architecture as part of the core team that launched the marketplace.

– Improved performance and resolved key bottlenecks in core marketplace flows.

Python Developer — Apr 2021 – Aug 2022: Buy Nothing (large-scale social network)

– Designed the architecture for a high-load application serving 2M+ users — live on the App Store:

apps.apple.com/us/app/buynothing/id1557679959

– Delivered the project on time against a tight investor-driven schedule, covering full feature scope.

Organizational contributions:

– Built the company's live-coding technical interview process from scratch; conducted interviews and delivered

candidate feedback.

– Led knowledge-sharing sessions and mentored engineers on individual growth plans.– Contributed to estimation and technical scoping for new projects.