Vasily Koval, Developer in Kyiv, Ukraine
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Vasily Koval

Verified Expert  in Engineering

Software Developer

Kyiv, Ukraine
Toptal Member Since
November 15, 2015

Vasily is a web developer with more than 10 years of extensive experience developing, optimizing, and supporting web applications. His main goal is to find solutions that meet all clients' requests with a focus on timely delivery. He also believes that accuracy and honesty are the keys to successful cooperation.


Just Eat
PHP 7, GitLab CI/CD, Agile Software Development, Codeception, PHPUnit, Laravel...
Vue, Laravel, PHPUnit, Git, CSS, HTML, MySQL, JavaScript, PHP, APIs, OpenAPI
PHP 7, MySQL, Laravel, Codeception, PHPUnit, Docker, Vagrant, APIs, OpenAPI




Preferred Environment

Git, PhpStorm, MacOS

The most amazing...

...thing I've coded is a web-based system to collect and manage orders for a taxi service.

Work Experience

PHP Engineer

2020 - PRESENT
Just Eat
  • Refactored an old monolith back end written in pure PHP into microservices.
  • Maintained Laravel-based microservices, adding new features, tests, and bug fixes.
  • Handled the delivery of new features to production.
Technologies: PHP 7, GitLab CI/CD, Agile Software Development, Codeception, PHPUnit, Laravel, Helmfile, Docker, APIs, OpenAPI

Web Developer

2012 - PRESENT
  • Created and supported a project for photographers, operators, and other staff from one side and for people who need staff like that from other side. Implemented some interesting features such as uploading and transcoding video files to specific for web formats (WebM, MP4), memberships, payments, etc.
  • Created online store based on OpenCart with the ability to export/import products for external systems, mass product/categories updates, viewing the group of products as one product, and multi-language support.
  • Contributed to smaller jobs to update and fix existing Laravel- and OpenCart-based websites as well as create new ones based on Laravel/MySQL/Twitter Bootstrap, etc.
Technologies: Vue, Laravel, PHPUnit, Git, CSS, HTML, MySQL, JavaScript, PHP, APIs, OpenAPI

PHP Engineer

2018 - 2020
  • Refactored old API back end written in Yii, into Laravel based application.
  • Added various features like offers, vouchers, image optimization, and GeoSearch.
  • Took care of reliability, deployments, and response time.
Technologies: PHP 7, MySQL, Laravel, Codeception, PHPUnit, Docker, Vagrant, APIs, OpenAPI

PHP Developer

2009 - 2018
Dating Factory
  • Created and updated features in admin panels: one for internal use and one for public use with the ability to configure websites, claims, view statistics, and more.
  • Worked with server-side scripts like daemons, mass-update scripts, and API calls.
  • Updated and maintained some secondary projects based on WordPress (including multi-site) and OpenX/Revive.
  • Created and updated promotional tools (static and dynamic) and collected some usage statistics.
  • Integrated external systems (such as tickets, payment, and tracking) via their API.
Technologies: jQuery, PHPUnit, JavaScript, HTML, PHP, APIs

PHP Developer

2007 - 2009
World Dating Partners
  • Developed and updated admin panels with functionality to create and edit websites, customers, view reports, and configure the main system.
  • Maintained WordPress-based blogs.
  • Worked with server-side scripts like daemons, mass-update scripts, API calls, etc.
  • Configured and sent big mailings, including checking the layouts, language, macros, and headers passed to email.
Technologies: Subversion (SVN), JavaScript, HTML, PHP

PHP Developer

2003 - 2007
  • Created a simple internal web application for bug and time tracking.
  • Created websites from scratch and based on osCommerce and xt:Commerce and Mambo/Joomla. Created templates, payment and shipping modules, calendars, modules to import and export products, etc.
  • Worked on a system to create and manage events that is currently installed in over thirty locations in Europe and the US.
Technologies: Subversion (SVN), JavaScript, CSS, HTML, MySQL, PHP

Creative Empowering Solutions (via Toptal)

Worked with internal sub projects such as registration wizard and JWT authentication server, implemented CRUDs for some entities.

Labstep (via Toptal)

Worked to improve unit testing, added a Vagrant container to help new team members, and added/refactored a REST API to connect the front and back end.

Getdressed2 (via Toptal)
Updated OpenCart and fixed problems with the payment system and template.

Dating Factory
White label platform to create and promote dating sites. Everything is prepared for success: cool templates, a lot of features, and detailed statistics.

OpenCart-based online store for a company which produces and sells furniture decorations. A lot of features were added to OpenCart: custom import, more statistics, DB optimization, grouped products, etc.


PHP, JavaScript, HTML, CSS, PHP 7, Bash


PHPUnit, Laravel, Codeception, JSON Web Tokens (JWT), Symfony, Yii


OpenCart, Docker, MacOS


APIs, Helmfile


Vue, OpenAPI, React, jQuery


PhpStorm, Git, Jira, GitLab CI/CD, NPM, Trello, Gulp, Vagrant, Sublime Text, Subversion (SVN)




Agile Software Development, Scrum, Refactoring

1999 - 2004

Master's Degree in Computer Science

Donetsk National University - Donetsk

Collaboration That Works

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