Designing and implementing database structures to support the functionality of a mobile application, using PostgreSQL to ensure high performance and query optimization.Creating and optimizing APIs for interaction between the mobile application and server services, including development based on gRPC for effective and secure data transmission between microservices.Successfully migrating part of the functionality from Python to Golang, which led to a significant increase in service performance and resilience.Developing and launching a fully functional chat system, supporting scalable web sockets and ensuring high communication reliability.Implementing a customized push notification system that increased user engagement and used advanced approaches to ensure instant message delivery.Integrating with external services, including using Redis to cache doctors' schedules obtained through an external service API. This helped reduce the load on partner services and accelerate access to frequently requested information.

Responsible for the backend development of a marketplace analytics web service, using the Go programming language. I designed and implemented functions for efficient collection, selection, and calculation of statistical information, ensuring accuracy and promptness of data.I introduced a feature that allows users to upload information into the service database via Excel, ensuring a smooth and user-friendly process.I developed a user API, which includes a function to update critical information about user products and orders. This feature enhanced user interaction with the service and improved their user experience.

Backend development on the Django and DRF frameworks.Working with databases and SQL queries.Improvement of existing projects, integration of external services.Setting up SMTP and email distribution.Improvement of the website admin panel.Integration of Django with the Stripe payment system.