Senior Backend Engineer (PHP / Symfony / Vue / React) Core Focus: High-load backend development, optimization
Aktualisiert am 21.09.2026
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 21.09.2026
Verfügbar zu: 100%
davon vor Ort: 50%
PHP
Symfony
Software Architecture
Laravel
MySQL
PostgreSQL
Redis
Database Optimization
REST API Design
Microservices
Docker
Git
CI/CD
JavaScript
Vue.js
Python
English
B2/C1 ? Professional Working / Advanced
Ukrainian
Native / C2
German
B1 ? Intermediate
Russian
Native / C2

Einsatzorte

Einsatzorte

Burgkirchen an der Alz (+100km)
Deutschland
möglich

Projekte

Projekte

5 years 5 months
2021-02 - 2026-06

High-load backend development

Senior Backend Developer (Contractor / Full-Time) PHP 8.4 Symfony MySQL ...
Senior Backend Developer (Contractor / Full-Time)

High-load backend development for the world?s leading online chess platform (10M+ DAU, 100M+ daily events).

  • Microservices Architecture: Refactored monolithic backend modules into scalable microservices using Symfony; designed internal REST APIs and utilized Protocol Buffers for fast inter-service communication.
  • Database & Query Optimization: Spearheaded backend performance tuning for massive concurrent traffic; refactored high-frequency MySQL queries and optimized indexes, achieving up to 30x reduction in query response time.
  • Platform Capabilities & SEO: Architected automated SEO pipelines, including site-wide dynamic sitemap generation, metadata management, and database schema updates.
  • Dynamic Media Rendering: Built dynamic image generation services using PHP GD library and Intervention Image to render real-time graphic assets from match data.
  • Observability: Integrated Datadog and Sentry for real-time monitoring and APM; developed background workers and Cron tasks to ensure high availability.

PHP 8.4 Symfony MySQL Redis Protocol Buffers Datadog Sentry GitHub REST APIs Microservices CI/CD
Chess.com Remote (Ukraine / Germany)
10 years 3 months
2010-12 - 2021-02

Delivered scalable web solutions

Freelance Full-Stack / Backend PHP Developer
Freelance Full-Stack / Backend PHP Developer

Delivered scalable web solutions, platforms, and analytics systems for international clients using PHP, Symfony, Laravel, MySQL, and PostgreSQL.

  • Product Analysis Platform (2014?2018): Built Amazon/Walmart data analysis system with Symfony, PostgreSQL, Redis, and AWS SQS. Optimized ~150 metrics, reducing processing time by 80% for 20M+ records.
  • Aviation CRM (2012?2014): Created aircraft maintenance CRM using Laravel, MySQL, and Python, focusing on data integration and operational stability.
  • Web Applications: Developed text-based online games, inspirational quote platforms (Laravel), and customized CMS plugins (WordPress/Drupal).

Upwork / Self-Employed Remote (Ukraine)
4 months
2010-09 - 2010-12

Developed web applications

PHP Developer
PHP Developer
  • Developed web applications using CodeIgniter, customizing CMS solutions and writing performant backend code under tight deadlines.
Behind the Ocean Zaporizhzhya, Ukraine
8 months
2010-02 - 2010-09

Developed "PHP Forms" platform

Support Specialist -> PHP Developer
Support Specialist -> PHP Developer
  • Promoted from support specialist to developer. 
  • Developed "PHP Forms" platform for visual form creation and contributed to internal CRM development.
Conkurent, LLC Zaporizhzhya, Ukraine
3 years 5 months
2006-06 - 2009-10

Led a sales department

Head of Sales Department
Head of Sales Department
  • Led a sales department, developing strong cross-functional communication, team management, and client consultation skills.
Foxtrot (Computer Hardware Retail) Zaporizhzhya, Ukraine
1 year 1 month
2005-05 - 2006-05

Developed people recognition algorithms in C++

Junior C++ Developer
Junior C++ Developer
  • Developed people recognition algorithms in C++ for video surveillance systems, focusing on real-time data processing and performance.
VIT (Video Internet Technologies) Zaporizhzhya, Ukraine

Aus- und Weiterbildung

Aus- und Weiterbildung

4 years 10 months
2001-09 - 2006-06

Computer Engineering - Specialist (5-year Program)

Master's Degree, Zaporizhzhia National Technical University (ZNTU)
Master's Degree
Zaporizhzhia National Technical University (ZNTU)
  • Specialized Computer Systems
  • Major in Specialized Computer Systems. Focus on software development, hardware-software integration, and system architecture.

Kompetenzen

Kompetenzen

Top-Skills

PHP Symfony Software Architecture Laravel MySQL PostgreSQL Redis Database Optimization REST API Design Microservices Docker Git CI/CD JavaScript Vue.js Python

Produkte / Standards / Erfahrungen / Methoden

Summary

Senior Backend Engineer with 15+ years of hands-on experience building, optimizing, and scaling web applications with a strong interest in high-load e-commerce and large-scale SaaS platforms. 5.5 years of experience developing Symfony-based microservices, refactoring legacy code, and optimizing databases for Chess .com (10M+ Daily Active Users). Proficient in modern PHP, high-load architecture, clean code practices, and query performance tuning. Work authorization: Valid residence & work permit in Germany (§24 Aufenthaltsgesetz ? Ukrainian protection status)


Skills

Core Backend & Architecture

  • PHP 8.4
  • Symfony
  • Laravel
  • Software Architecture
  • Microservices
  • RESTful API Design
  • OOP / Design Patterns
  • PHPUnit
  • Composer
  • CodeIgniter


Databases & Caching (High-Load / Scalability)

  • MySQL
  • Query Optimization & Indexing
  • PostgreSQL
  • Redis
  • Memcached
  • MariaDB
  • Database Transactions


DevOps, Infrastructure & Observability

  • Protocol Buffers (Proto)
  • Datadog
  • Sentry
  • Git / GitHub
  • CI/CD
  • Docker
  • Nginx
  • Apache
  • AWS (SQS S3)
  • Kafka


Frontend, Engineering Practices & Tools

  • Vue.js
  • JavaScript / jQuery
  • Bootstrap
  • HTML5 / CSS3
  • Code Review
  • Clean Code
  • AI-Assisted Development
  • Jira
  • Python (Django)
  • C++

Datenbanken

MySQL
MariaDB
PostgreSQL

Einsatzorte

Einsatzorte

Burgkirchen an der Alz (+100km)
Deutschland
möglich

Projekte

Projekte

5 years 5 months
2021-02 - 2026-06

High-load backend development

Senior Backend Developer (Contractor / Full-Time) PHP 8.4 Symfony MySQL ...
Senior Backend Developer (Contractor / Full-Time)

High-load backend development for the world?s leading online chess platform (10M+ DAU, 100M+ daily events).

  • Microservices Architecture: Refactored monolithic backend modules into scalable microservices using Symfony; designed internal REST APIs and utilized Protocol Buffers for fast inter-service communication.
  • Database & Query Optimization: Spearheaded backend performance tuning for massive concurrent traffic; refactored high-frequency MySQL queries and optimized indexes, achieving up to 30x reduction in query response time.
  • Platform Capabilities & SEO: Architected automated SEO pipelines, including site-wide dynamic sitemap generation, metadata management, and database schema updates.
  • Dynamic Media Rendering: Built dynamic image generation services using PHP GD library and Intervention Image to render real-time graphic assets from match data.
  • Observability: Integrated Datadog and Sentry for real-time monitoring and APM; developed background workers and Cron tasks to ensure high availability.

PHP 8.4 Symfony MySQL Redis Protocol Buffers Datadog Sentry GitHub REST APIs Microservices CI/CD
Chess.com Remote (Ukraine / Germany)
10 years 3 months
2010-12 - 2021-02

Delivered scalable web solutions

Freelance Full-Stack / Backend PHP Developer
Freelance Full-Stack / Backend PHP Developer

Delivered scalable web solutions, platforms, and analytics systems for international clients using PHP, Symfony, Laravel, MySQL, and PostgreSQL.

  • Product Analysis Platform (2014?2018): Built Amazon/Walmart data analysis system with Symfony, PostgreSQL, Redis, and AWS SQS. Optimized ~150 metrics, reducing processing time by 80% for 20M+ records.
  • Aviation CRM (2012?2014): Created aircraft maintenance CRM using Laravel, MySQL, and Python, focusing on data integration and operational stability.
  • Web Applications: Developed text-based online games, inspirational quote platforms (Laravel), and customized CMS plugins (WordPress/Drupal).

Upwork / Self-Employed Remote (Ukraine)
4 months
2010-09 - 2010-12

Developed web applications

PHP Developer
PHP Developer
  • Developed web applications using CodeIgniter, customizing CMS solutions and writing performant backend code under tight deadlines.
Behind the Ocean Zaporizhzhya, Ukraine
8 months
2010-02 - 2010-09

Developed "PHP Forms" platform

Support Specialist -> PHP Developer
Support Specialist -> PHP Developer
  • Promoted from support specialist to developer. 
  • Developed "PHP Forms" platform for visual form creation and contributed to internal CRM development.
Conkurent, LLC Zaporizhzhya, Ukraine
3 years 5 months
2006-06 - 2009-10

Led a sales department

Head of Sales Department
Head of Sales Department
  • Led a sales department, developing strong cross-functional communication, team management, and client consultation skills.
Foxtrot (Computer Hardware Retail) Zaporizhzhya, Ukraine
1 year 1 month
2005-05 - 2006-05

Developed people recognition algorithms in C++

Junior C++ Developer
Junior C++ Developer
  • Developed people recognition algorithms in C++ for video surveillance systems, focusing on real-time data processing and performance.
VIT (Video Internet Technologies) Zaporizhzhya, Ukraine

Aus- und Weiterbildung

Aus- und Weiterbildung

4 years 10 months
2001-09 - 2006-06

Computer Engineering - Specialist (5-year Program)

Master's Degree, Zaporizhzhia National Technical University (ZNTU)
Master's Degree
Zaporizhzhia National Technical University (ZNTU)
  • Specialized Computer Systems
  • Major in Specialized Computer Systems. Focus on software development, hardware-software integration, and system architecture.

Kompetenzen

Kompetenzen

Top-Skills

PHP Symfony Software Architecture Laravel MySQL PostgreSQL Redis Database Optimization REST API Design Microservices Docker Git CI/CD JavaScript Vue.js Python

Produkte / Standards / Erfahrungen / Methoden

Summary

Senior Backend Engineer with 15+ years of hands-on experience building, optimizing, and scaling web applications with a strong interest in high-load e-commerce and large-scale SaaS platforms. 5.5 years of experience developing Symfony-based microservices, refactoring legacy code, and optimizing databases for Chess .com (10M+ Daily Active Users). Proficient in modern PHP, high-load architecture, clean code practices, and query performance tuning. Work authorization: Valid residence & work permit in Germany (§24 Aufenthaltsgesetz ? Ukrainian protection status)


Skills

Core Backend & Architecture

  • PHP 8.4
  • Symfony
  • Laravel
  • Software Architecture
  • Microservices
  • RESTful API Design
  • OOP / Design Patterns
  • PHPUnit
  • Composer
  • CodeIgniter


Databases & Caching (High-Load / Scalability)

  • MySQL
  • Query Optimization & Indexing
  • PostgreSQL
  • Redis
  • Memcached
  • MariaDB
  • Database Transactions


DevOps, Infrastructure & Observability

  • Protocol Buffers (Proto)
  • Datadog
  • Sentry
  • Git / GitHub
  • CI/CD
  • Docker
  • Nginx
  • Apache
  • AWS (SQS S3)
  • Kafka


Frontend, Engineering Practices & Tools

  • Vue.js
  • JavaScript / jQuery
  • Bootstrap
  • HTML5 / CSS3
  • Code Review
  • Clean Code
  • AI-Assisted Development
  • Jira
  • Python (Django)
  • C++

Datenbanken

MySQL
MariaDB
PostgreSQL

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