# Andrii Korenev

Andrii Korenev is a remote worker on Himalayas, Senior Backend Developer at Chess.com, based in Germany.

Source: https://himalayas.app/@andriikorenev

```text
Senior Backend Developer at Chess.com who cut MySQL query response time by up to 30x and built Symfony microservices.
```

| Detail | Value |
| --- | --- |
| Availability | Looking for a job |
| Location | Germany |
| Authorized to work in | Germany |
| Salary expectations | 62k+ EUR |
| Job categories | Backend Engineer, Full Stack Developer |
| Skills | PHP, Symfony, Backend Development, Software Architecture, Microservices, REST API Design, MySQL, Query Optimization, Database Indexing, PostgreSQL, Redis, Laravel, high load systems, Protocol Buffers, PHP GD |
| LinkedIn | https://linkedin.com/in/Andrii-Korenev |
| GitHub | https://github.com/kageua |

## What I'm looking for

```text
I’m interested in high-load e-commerce and large-scale SaaS platforms, where I can develop backend systems and work on performance, scalability, and database optimization.
```

## About

```text
At Chess.com, I refactored monolithic backend modules into Symfony microservices and designed internal REST APIs using Protocol Buffers. I also tuned high-frequency MySQL queries and indexes, reducing query response time by up to 30x.

As a freelance PHP developer, I built an Amazon and Walmart data analysis platform that reduced processing time by 80% for 20M+ records. I’ve also developed web applications and CRM systems using PHP, Symfony, Laravel, MySQL, and PostgreSQL.
```

## Experience

### Senior Backend Developer

[Chess.com](https://himalayas.app/companies/chess-com). Feb 2021 - Jun 2026

```text
High-load backend development for the world's leading online chess platform (10M+ DAU, 100M+ daily events). Refactored monolithic modules into microservices, optimized MySQL queries achieving up to 30x reduction in response time, and built automated SEO pipelines and dynamic image generation services.
```

Skills: PHP-8+, Symfony, MySQL, Redis, Protocol-Buffers, Datadog, Sentry, GitHub, REST-APIs, Microservices, CI-CD, Query-Optimization, Indexing, PHP-GD, Intervention-Image, Cron, Background-Workers

### Freelance Full-Stack / Backend PHP Developer

[Upwork / Self-Employed](https://himalayas.app/companies/upwork). Dec 2010 - Feb 2021

```text
Delivered scalable web solutions, platforms, and analytics systems for international clients using PHP, Symfony, Laravel, MySQL, and PostgreSQL. Built a product analysis platform for Amazon/Walmart data, an aviation maintenance CRM, and various web applications.
```

Skills: PHP, Symfony, Laravel, MySQL, PostgreSQL, Redis, AWS-SQS, Python, WordPress, Drupal, CodeIgniter, REST-APIs, Data-Analysis, CRM-Development

### PHP Developer

Behind the Ocean. Sep 2010 - Dec 2010

```text
Developed web applications using CodeIgniter, customizing CMS solutions and writing performant backend code under tight deadlines.
```

Skills: PHP, CodeIgniter, CMS, Backend-Development

### Support Specialist -\> PHP Developer

Conkurent, LLC. Feb 2010 - Sep 2010

```text
Promoted from support specialist to developer. Developed a PHP Forms platform for visual form creation and contributed to internal CRM development.
```

Skills: PHP, CRM, Web-Development

### Head of Sales Department

Foxtrot. Jun 2006 - Oct 2009

```text
Led a sales department, developing strong cross-functional communication, team management, and client consultation skills.
```

Skills: Team-Management, Sales, Client-Consultation, Communication-Skills

### Junior C++ Developer

VIT. May 2005 - May 2006

```text
Developed people recognition algorithms in C++ for video surveillance systems, focusing on real-time data processing and performance.
```

Skills: C++, Real-time-Data-Processing, Algorithm-Development, Video-Surveillance

## Education

### Zaporizhzhia National Technical University (ZNTU)

Master's Degree, Specialized Computer Systems. 2001 - 2006

```text
Master's Degree in Computer Engineering from Zaporizhzhia National Technical University, specializing in specialized computer systems with a focus on software development, hardware-software integration, and system architecture.
```

## Tech stack

- GitHub
- MySQL
- PostgreSQL
- MariaDB
- Memcached
- Sentry
- Django
- Laravel
- Symfony
- Bootstrap
- Redis
- Jira
- Vue.js
- jQuery
- JavaScript
- Python
- HTML5
- PHP
- C++
- Kafka
- Datadog
- WordPress
- Drupal
- PHPUnit
- Git
- Docker
- NGINX
- CodeIgniter
- Composer

To contact Andrii, message them from this profile with a Himalayas employer account: [Hire on Himalayas](https://himalayas.app/hire).

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