Serhii Brytskyi

Experience

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  Freelance.RU - Одна из крупнейших русскоязычных бирж удаленной работы.

  Jan 2008 - Aug 2014

  PHP/JS Developer as Freelancer
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  ITC, R&D

  Sept 2015 - Jul 2017

  PHP Backend Developer

  - Working extensively with popular CMS platforms like WordPress, Joomla, OpenCart, and Prestashop, ensuring improved performance and maintainability.

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  482.solutions

  Nov 2016 - Apr 2020

  Senior NodeJS Developer

  - Focused on Node.js development for a key project, where I acted as the system architect for a job search platform tailored for the maritime industry. Developed a robust backend architecture using Node.js and Express, implementing TDD principles with Mocha and Chai for thorough testing and code reliability.- Built a comprehensive referral and job matching system, integrating CV parsing and automated candidate-vacancy matching. Enhanced the platform with a seamless integration of various payment gateways, ensuring secure and efficient transactions.- Optimized MongoDB queries and designed scalable database structures, which improved data retrieval times and reduced response latency, enhancing user experience across high-traffic applications. Show less

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  World Business & Executive Coach Summit (WBECS)

  Jul 2017 - Sept 2018

  PHP/JS Back-end Developer

  - Developed a robust backend system for a distance learning platform, using PHP and JavaScript, to facilitate interactive coaching sessions and manage user interactions. Built features for scheduling, session tracking, and user progress monitoring.- Integrated multiple payment gateways, enabling secure transactions and automated billing for users, while ensuring compliance with industry standards for payment processing.- Implemented a role-based access control (RBAC) system, streamlining user management and enhancing the security of the platform by defining and managing permissions across different user roles.- Automated portal creation processes, reducing manual effort and improving the scalability of the platform. Enhanced user experience by optimizing backend performance and implementing efficient data handling strategies. Show less

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  StayHired®

  Aug 2019 - Dec 2021

  - Optimized backend architecture built on ColdFusion and significantly improved performance by tuning JVM settings and optimizing complex MySQL queries and stored procedures. This reduced system latency and improved the overall responsiveness of the application.- Migrated core business logic from monolithic ColdFusion backend to modern Node.js microservices, leveraging local ML models (Python) for enhanced data processing and analysis. Collaborated on the development of scrapers and automation tools for LinkedIn data, ensuring compliance with best practices for data handling.- Designed and implemented scalable Node.js microservices, integrating them seamlessly with the existing infrastructure and handling high-load scenarios. These services included API endpoints, data processing pipelines, and integration with local machine learning models.- Enhanced data retrieval efficiency by analyzing and optimizing database indices and performing deep query optimization, reducing query execution times by up to 40%. Show less

  • Tech Lead

    Aug 2020 - Dec 2021

  • Senior Backend Engineer

    Aug 2019 - Aug 2020
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  NDA

  Aug 2021 - Oct 2024

  Senior NodeJS Developer — Fintech/Crypto Exchange Platform

  - Played a key role in migrating from a monolithic architecture to a microservices-based system, utilizing Redis and TCP for initial communication, and later transitioning to RabbitMQ for better scalability and reliability. This shift significantly improved system resilience and fault tolerance under high-load conditions.- Developed and integrated solutions for CEX (Centralized Exchanges) and DEX (Decentralized Exchanges), implementing seamless API interactions with major platforms and liquidity providers such. Gained deep understanding of CEX workflows, including trading, order management, and liquidity aggregation.- Built a hierarchical wallet microservice capable of generating wallets using private keys, supporting hierarchical deterministic (HD) wallets, and managing various blockchain assets. The service ensured secure transactions and real-time synchronization with blockchain nodes.- Enhanced backend infrastructure, resolving complex issues like incorrect type mapping via mikro-orm, problems with passing messages with non-ASCII characters in Redis. Eliminated singleton overrides in high-concurrency scenarios to ensure robust state management and consistent API responses.- Optimized real-time data processing and API communication, enabling efficient synchronization between internal microservices and external blockchain platforms. Collaborated with cross-functional teams to streamline decentralized finance (DeFi) integrations, bridging the gap between traditional fintech and modern Web3 solutions.- Maintained high code quality through rigorous testing and code reviews, ensuring robust architecture, minimizing technical debt, and enhancing maintainability. Show less