Senior Backend Engineer

Founded and registered a software startup, serving as the sole engineer across product, backend, and mobile development. Shipped NoWow, a cross-platform subscription tracker with a Flutter client for iOS and Android and a .NET backend, including app store submission and release.

Built a reminder pipeline that notifies users of upcoming subscription charges through push notifications and email, scheduled according to renewal dates. The product reached more than 300 active users globally within its first month.

Designed and built a Rust order matching engine for spot and futures cryptocurrency markets, supporting limit, market, stop-market, iceberg, take-profit, stop-loss, and post-only orders with real-time order book events.

Built liquidation and position risk management systems that reduced losses from under-margined positions. Contributed to multi-blockchain wallet infrastructure, integrated KYC APIs for fraud and anti-money laundering compliance, and profiled critical database queries to identify and fix hidden defects.

Built a .NET data extraction service using Playwright to collect structured records from ten public sources into a normalized machine learning data pipeline. Sustained throughput of hundreds of records per second through asynchronous pipelining and concurrent page handling.

Implemented resilient shadow DOM traversal for web components and streamed output to a downstream sanitization and filtering service over raw TCP sockets with binary framing, reducing HTTP overhead on the critical path.

Built the Bet Settlement service for more than 800 outcomes across football, basketball, handball, and baseball. Implemented eventing and aggregation with a third-party odds provider to enable near-instant settlement and payouts after outcomes were determined.

Refactored backend data handling to meet gaming regulatory requirements and wrote more than 1,500 unit tests across core components. Implemented WebSocket feeds, Firebase Admin push notifications, and OpenAPI documentation to improve real-time client updates and frontend delivery.

Participated in the production database migration from Airtable to PostgreSQL with zero data loss, delivering significant query performance improvements. Created automation scripts and unit tests for schema type mapping, eliminating manual work and reducing team workload.

Designed and built a Matching Service for a family matching algorithm with more than 20 parameters. The service ranked and scored families, replaced the existing system, improved accuracy on the same datasets, and contributed to positive user feedback. Also contributed to system design and architecture decisions.