● Designed and implemented data migration from legacy storage systems to new infrastructure with zero downtime and no data loss. ● Developed backend services for an internal ERP platform using NestJS, supporting business analytics and operational management. ● Built services for management dashboards covering financial metrics, sales, product assortment, and customizable data views. ● Developed a marketplace review analytics service aggregating customer reviews across selected time periods, including classification and issue analysis. ● Integrated ML/NLP models developed by the Data Science team into backend services through FastAPI; implemented APIs and business logic for automated review classification. ● Implemented a manual review and approval workflow for managers to validate classification results for subsequent supervised model retraining. ● Developed competitor intelligence services for product matching, statistics, and detailed analysis of direct competitors. ● Developed advertising analytics services for evaluating and comparing campaign performance. ● Contributed to a market intelligence platform for the Russian consumer electronics market, including segmentation, ABC analysis, and analytical dashboards. ● Implemented monitoring of key performance metrics, reducing the time to detect critical issues by approximately 30%. ● Created architectural documentation and system diagrams for fault tolerance and horizontal scalability.

● Designed and built the backend architecture from scratch using Clean Architecture and Hexagonal Architecture principles. ● Developed server-side business logic and APIs supporting loads of up to 2,000 RPS. ● Implemented asynchronous service communication through RabbitMQ, eliminating blocking issues during peak loads. ● Covered critical business logic with unit and integration tests using Jest; achieved 90%+ test coverage. ● Set up Docker, CI/CD pipelines, and monitoring in collaboration with DevOps. ● Integrated ML/NLP components through FastAPI for processing and classification of user-generated text data.

● Designed and built a microservice-based backend architecture from scratch for a crypto ecosystem and integration of new gaming projects. ● Developed authentication and account linking through crypto wallets using Ethers.js. ● Developed and tested Solidity smart contracts for Web3 product features. ● Implemented token donation processing using on-chain events and automatic crediting of funds to users' in-game balances. ● Built a P2P exchange inside a Telegram bot with atomic processing and transaction safety.