Maxim Skrinnik

Backend Developer

I'm involved in the development of the ASO platform.

• Resolved several platform bugs, which have generally improved platform performance, reduced the number of database queries, and increased its stability by adding database transactions.

Fullstack Developer

Developed a vending machine interface, a mobile app for managing the vending machine with real-time information, and a full-stack backend system with a microservices architecture. Frontend (vending machine interface) using React + TypeScript + Tailwind CSS. Optimized for 600px wide touchscreens, wrapped with Electron.JS. Mobile app using React Native + TypeScript, Expo, and Native Modules for iOS and Android. Developed an operator dashboard with real-time status information: inventory balances, equipment errors, machine status changes, and receiving tasks for a specific machine with checklists. Developed a system with push notifications via an FCM token in Firebase. Backend: Node.JS (NestJs), microservice architecture, RabbitMQ (event model and task queues), PostgreSQL (schema design, indexing, query optimization), Redis (caching, pub/sub), WebSocket for real-time updates.

Fullstack Developer

Frontend: React + TypeScript + Next.js, pure CSS (no UI libraries). Custom components, SSR, performance optimization. Developed approximately 50% of the frontend application, including the following pages: home, profile, daily map, list of all maps, and so on. Developed a semicircle animated chart (canvas + CSS transforms) without libraries. Backend: NodeJs (NestJs), PostgreSQL, REST API, PostgreSQL. Designed the database structure for storing users, layouts, and interpretations. Implemented personalized layout generation, calculation business logic, and asynchronous processing of user requests. Implemented a microservice for working with ChatGpt, which can store context. Optimized SQL queries and added indexing to speed up retrieval. Telegram bot. Custom date picker library with extended functionality. Implemented integration of Kaiten services with Amo CRM. Creating a task in Kaiten creates a task in Amo for the same person with the same data (description, deadlines, completion status). Changing tasks in one service also changes the task in the other. Implemented using Node.js, Express, TypeScript, and cron tasks.

• Developed a semicircle animated chart (canvas + CSS transforms) without libraries: Smooth arc fill animation, Adaptability to any screen size.
• Optimized SQL queries and added indexing to speed up retrieval.

Backend Developer

Participated in the development of the marketplace. Participated in the development of server-side logic for web games with Python (FastApi) and Node.JS (Express).

• Implemented: Real-time chat (WebSocket), JWT authentication and session management, Full Swagger API documentation, FastAPI, PostgreSQL, Redis.

Backend Developer

Development of custom commercial APIs and backend systems (e-commerce, CRM, Telegram services). Design of microservice architectures (FastAPI, Celery, Node.JS, NestJs, Express, Redis, RabbitMQ). PostgreSQL optimization (indexes, complex JOINs, EXPLAIN ANALYZE). Implementation of real-time services (WebSocket, pub/sub). Integration with payment systems and external APIs. Dockerization of projects, deployment to Linux servers. Support and refactoring of legacy Node.js services.