Sergey Mazaev Email & Phone Number

Russia

Moscow, Russia

Belgrade, Serbia

Enhancement and Maintenance of an Internal Landing Page BuilderImplemented localization of images and videos, enabling the creation of multilingual landing pages with different images for various localization languages.Developed a service for generating HTML based on a JSON schema of the landing page.Stack: JavaScript, TypeScript, React, Redux, Jest, Node.js, Express, PostgreSQL

Application Enhancing GPT Chat CapabilitiesAn application that expands the basic functionalities of ChatGPT through a Telegram bot and a website - chataibot.ru.Implemented a microservice for processing text from images.Added the capability for ChatGPT to work with voice in the Telegram bot.Added support for Google Maps in ChatGPT responses.Result:A Telegram bot and website used daily by over 10,000 people.Stack: React, Next.js, ChakraUI, Typescript, Telegram API, Node.js, Express.js, PostgreSQL, TypeORMFood Delivery Application in Sri LankaA food delivery application from restaurants implemented as a Telegram bot.Designed the backend architecture and database.Implemented the main functionality of the application including order creation by clients and route planning for couriers.Set up CI/CD for automatic deployment and test execution.Result:A Telegram bot that enables users to create over 10 restaurant orders daily.Stack: React, Typescript, Telegram API, Node.js, Nest.js, PostgreSQL, TypeORM

Moscow, Russia

Themed UI-Kit for Internal UseA UI-kit designed for optimal use within the company, allowing developers to integrate the design system into their projects with minimal time expenditure.Set up Storybook and CI/CD.Implemented components for the library.Responsible for project documentation.Result:An internal library that reduced the start time for new projects by more than a week.Configured pipelines for:package publishing;creating change notes;deploying the updated Storybook.Stack: React, Typescript, TailwindCSS, StorybookLibrary for Generating Forms Based on GraphQL SchemaA package that allowed generating code for input/editing/viewing screens of business entities.Analyzed existing solutions for similar tasks.Integrated ready-made solutions into the developing library.Developed the part of the package responsible for generating view pages and building tables with necessary actions on the page.Implemented documentation practices.Result:The developed library accelerated the development of typical screens from one or two days to several hours.Up-to-date documentation reduced intra-team interaction by 70%.Stack: React, Typescript, GraphQL, UniformWeb Application for Working with Genetic MaterialAn application for laboratory accounting of genetic material.Set up CI/CD.Integrated internal UI-kit packages and the form generation library.Implemented several screens for the application according to the requirements.Covered 20% of the total codebase with tests.Result:Integration of internal packages reduced development time by 30% compared to similar projects.Test coverage reduced labor costs for regression testing by 40% compared to similar projects.Stack: React, Next.js, Typescript, GraphQL, Apollo

Application for aggregating information about artificial diamonds. The application allowed laboratories to upload information about their stones in a convenient format for them, and clients to view and order stones.Implemented data parsing from uploaded files and adding information to the database.Optimized existing database queries.Increased test coverage to 50% of the total codebase.Set up frontend logging.Migrated the application from the old authentication system to Firebase.Result:Reduced data retrieval request time from 600ms to 150ms, and data addition time from 5 minutes to 24 seconds.Enabled the detection of hard-to-reproduce bugs on the frontend thanks to the logging system.Stack: React, MaterialUI, Redux, Typescript, Node.js, Nest.js, PostgreSQL, TypeORMApplication for analyzing AI performance in board games. An application for searching and analyzing AI actions in games based on specified criteria.Refactored the monolith into microservices.Improved database queries.Fixed known bugs.Result:Reduced the execution time of the heaviest queries from 15 minutes to 20 seconds.Independent parts of the application became separate services, simplifying maintenance and speeding up the addition of new functionality.Stack: Java, TypeScript, SQL, React