Igor Kirey, Developer in Kiev, Ukraine
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Igor Kirey

Verified Expert  in Engineering

JavaScript Developer

Kiev, Ukraine
Toptal Member Since
March 20, 2015

Igor is a skilled full-stack developer with experience in website, front-end, and back-end development and creating APIs for mobile applications. He is certified by AWS and has architecting and maintenance experience. Igor is comfortable working with different social and payment APIs and various frameworks.


Vesta Software LLC
AWS Lambda, Amazon Web Services (AWS), TypeScript, Amazon DynamoDB...
Illustria, Inc
React, HTML, JavaScript, CSS, TypeScript, Sentry
SportsCardInvestor (via Toptal)
JavaScript, React, Node.js, Serverless, PostgreSQL, Next.js, Scrum, Agile...




Preferred Environment

Amazon Web Services (AWS), React, Node.js, Agile, TypeScript

The most amazing...

...thing I've developed is Analytics 360, an application for Colorado University.

Work Experience

Team Lead and Back-end Developer

2022 - 2023
Vesta Software LLC
  • Used the AWS Cloud Development Kit (CDK) to create the whole infrastructure. Added required Amazon Cognito, AWS Lambda, Amazon DynamoDB, and Amazon S3 resources and settings.
  • Implemented new AWS Lambda functions for managing user's content and handling required business logic. I also created unit tests.
  • Reviewed client's requirements, helped organize the work process, and performed part of the project management work.
Technologies: AWS Lambda, Amazon Web Services (AWS), TypeScript, Amazon DynamoDB, API Gateways, Amazon Connect, JavaScript, React, Node.js

Front-end Developer

2022 - 2022
Illustria, Inc
  • Refactored most of the code, improved the structure, optimized components, and increased the performance and UX.
  • Moved the existing codebase to the latest React version and wrote unit tests.
  • Maintained the app, added more features, and worked on a responsive version.
Technologies: React, HTML, JavaScript, CSS, TypeScript, Sentry

Full-stack React and Node.js Developer

2021 - 2022
SportsCardInvestor (via Toptal)
  • Expanded and evolved analytics platform. Added new features, including screens, interactions, and workflows, improved the existing ones (e.g., for managing client's content), resolved bugs, etc.
  • Implemented new API endpoints for the main web platform and more endpoints for the mobile app (Node.js).
  • Implemented new AWS Lambda functions (serverless), background jobs processing external data and populating the database.
Technologies: JavaScript, React, Node.js, Serverless, PostgreSQL, Next.js, Scrum, Agile, Full-stack, AWS Lambda, Amazon EC2, Amazon Simple Queue Service (SQS), Amazon S3 (AWS S3), Amazon Web Services (AWS), SCSS, YARN, NPM, WebStorm, TypeScript, Axios, Asana, JSON Web Tokens (JWT), REST, HTML, CSS, CSS3, HTML5, MongoDB, GitHub, REST APIs, Express.js, Less, Sentry, Google Analytics, Continuous Integration (CI), Continuous Delivery (CD), Continuous Deployment, JSX, Single-page Applications (SPA), SQL, Git, Heroku

Front-end Developer

2021 - 2021
UseLantern (via Toptal)
  • Added new and refactored old website pages and responsive styles for mobile and desktop devices (React).
  • Migrated React to Next.js completely and deployed to the Firebase (hosting and functions).
  • Integrated Stripe into the main payment flow (subscription plans and checkout). Implemented new auth flow using Firebase API (registration, login, restore password, confirm email).
Technologies: React, Stripe API, Next.js, Front-end, Stripe, Full-stack, SCSS, YARN, NPM, WebStorm, Axios, Firebase, Single-page Applications (SPA), HTML, CSS, JavaScript, CSS3, HTML5, GitHub, Web Design, Google Analytics, Figma, JSX, Git

Front-end Developer

2019 - 2021
CourtCorrect (via Toptal)
  • Implemented new responsive templates based on provided designs (using modern React features, HTML5, and CSS3).
  • Created a convenient complex dashboard that helps clients manage their personal data easily.
  • Developed a special reusable component for scrolling content with slides.
  • Built a Chrome extension for quick access to the platform's features and content. While browsing, regular users can see interesting and helpful information without opening the main app.
Technologies: CSS3, HTML5, React, JavaScript, Stripe API, Front-end, Chrome Extensions, Stripe, SCSS, NPM, Axios, HTML, CSS, GitHub, JSX, Single-page Applications (SPA), Git, Search Engine Optimization (SEO), Heroku

Full-stack Developer

2016 - 2019
University of Colorado (via Toptal)
  • Created a cool application for collecting and representing analytics based on React and Node.js frameworks.
  • Implemented a custom menu component, which looks like a subway map (using the D3.js library). Each item in the menu was represented as a station. Integrated a special tool in the admin portal to manage the content of that menu.
  • Implemented logic for online user notifications based on Socket.IO. Integrated Tableau using their API to the main platform.
  • Created HTML5/CSS3 templates with the mockups provided. Created a website for a hackathon (WordPress) and implemented a responsive template from scratch.
  • Implemented user onboarding walkthrough feature (tutorial), which explains how to use the app step by step. Created an admin portal completely for the main platform (React and Node.js).
Technologies: WordPress, CSS3, HTML5, Socket.IO, D3.js, Webpack, Node.js, RefluxJS, React, JavaScript, Front-end, Agile, Full-stack, SCSS, NPM, Axios, Asana, Basecamp, Object-oriented Programming (OOP), HTML, CSS, MongoDB, Tableau, Redux, REST APIs, Express.js, JSX, Single-page Applications (SPA)

Node.js Developer

2016 - 2016
Incertidum (via Toptal)
  • Improved the speed of application API methods. Implemented additional logic for API methods.
  • Enhanced the structure of the application and development process.
  • Added new features for the application's UI. Added new API methods.
Technologies: CSS, HTML, JavaScript, RethinkDB, Gulp, Node.js, NPM, Asana, REST, MySQL, Express.js, SQL

Back-end Node.js Developer

2016 - 2016
Veoo, Ltd. (via Toptal)
  • Worked with AWS, set up environments, and fixed issues. Worked with DockerHub and RabbitMQ services.
  • Implemented new features for the client's platform, new APIs, and microservices.
  • Fixed the client's platform issues, investigated the codebase, and researched logs.
  • Created shell scripts for managing logs and backups. Set up the environment with a node cluster using Kubernetes.
Technologies: Amazon Web Services (AWS), RabbitMQ, Docker, Node.js, MongoDB, NPM, Asana, REST, JavaScript, MySQL, GitHub, REST APIs, Express.js, SQL, Git

Meteor and React Developer

2016 - 2016
Notum, Ltd. (via Toptal)
  • Created new sections and expanded (improved or refactored) necessary functionality for the application.
  • Applied HTML/CSS templates provided by the client. Fixed the style and logic bugs.
  • Expanded the logic for uploading files using AWS. Improved the structure of the existing database.
Technologies: Amazon Web Services (AWS), MongoDB, CSS, HTML, Meteor, React, Front-end, SCSS, NPM, JavaScript, CSS3, JSX, Single-page Applications (SPA)

Front-end React and Back-end Node.js Developer

2015 - 2016
IvySpace (via Toptal)
  • Improved the continuous integration development process with GitHub, AWS, and Codeship. Set up environments and fixed issues.
  • Created HTML/CSS templates with the mockups provided. Built the admin panel for the main application based on React and expanded a custom design.
  • Expanded necessary functionality for the React application. Created API methods and wrote the tests and documentation.
Technologies: RefluxJS, GitHub, Amazon Web Services (AWS), CSS, HTML, Gulp, Node.js, React, JavaScript, Front-end, Full-stack, SCSS, NPM, Axios, Codeship, Asana, REST, Socket.IO, HTML5, Redux, REST APIs, Less, Continuous Integration (CI), Continuous Delivery (CD), Continuous Deployment, JSX, Single-page Applications (SPA), Git

Full-stack Developer

2015 - 2015
Homeful (via Toptal)
  • Implemented a new design for the company's website alongside the CTO and a designer.
  • Built lightweight and responsive templates using HTML5 and CSS3.
  • Implemented new APIs to fit the client's requirements. Maintained the legacy code and refactored old features.
Technologies: CoffeeScript, Meteor, Single-page Applications (SPA)

Back-end Developer

2013 - 2014
  • Created APIs for mobile applications, iOS and Android. Worked with AWS, including EC2, SNS, and SQS.
  • Wrote integration and unit tests. Improved the internal web app framework of the company.
  • Worked with Google, Facebook, and Twilio APIs to extend existing functionalities.
Technologies: CSS, HTML, Redis, MongoDB, Node.js, PHP, Scrum, Agile, Full-stack, AWS Lambda, Amazon EC2, Amazon Simple Queue Service (SQS), Amazon S3 (AWS S3), Amazon Web Services (AWS), NPM, Twitter API, REST, Object-oriented Programming (OOP), Twilio, JavaScript, CSS3, HTML5, MySQL, REST APIs, Twilio API, SQL

Full-stack Developer

2012 - 2013
  • Created the corporate sites, stores, and portfolios. Wrote modules for CMS systems.
  • Worked with the internal frameworks of the company. Improved the internal CRM and company website.
  • Worked with different APIs, e.g., Google, Facebook, and Twitter, to implement new features or extend existing features.
Technologies: CSS, HTML, JavaScript, MySQL, PHP, Front-end, Scrum, Full-stack, Adobe Photoshop, Memcached, Object-oriented Programming (OOP), CSS3, HTML5, jQuery, WordPress, Web Design, SQL, Search Engine Optimization (SEO)

Full-stack Developer

2008 - 2012
  • Created corporate sites, stores, portfolios, and landing pages. Designed sites and different UI components.
  • Developed with different social and payment APIs to implement new or improve existing features.
  • Worked with different CMSs, including WordPress, OpenCart, and LiveStreet. Also used different self-made frameworks like Zend, CodeIgniter, etc.
Technologies: CSS, HTML, JavaScript, MySQL, PHP, Front-end, Full-stack, RabbitMQ, Mercurial, Adobe Photoshop, Memcached, Object-oriented Programming (OOP), Socket.IO, Redis, CSS3, HTML5, jQuery, WordPress, Elasticsearch, Web Design, SQL, Search Engine Optimization (SEO)

Lantern Seamless Insights

Lantern is your assistant in the market. The project was built to streamline terabytes of trades and extract the ones never meant to be seen by the retail investor. It delivers next-generation AI-driven insights to help the world trade smarter through options.


CourtCorrect is a platform to resolve all types of disputes; basically, it's a low-risk, affordable, accessible online legal system. It's a place to solve legal problems via a swift, friendly process that encourages settlements and a centralized platform to manage all cases at all stages.


CSS, HTML, CSS3, HTML5, PHP, JavaScript, Sass, Less, TypeScript, SCSS, CoffeeScript, SQL


Express.js, Next.js, YARN, Redux, JSON Web Tokens (JWT), AngularJS


React, Node.js, REST APIs, Socket.IO, RefluxJS, Mustache, D3.js, Google API, Twitter API, jQuery, Facebook API, Stripe API, Stripe, Twilio API


Asana, NPM, Amazon Simple Queue Service (SQS), JSX, Codeship, Webpack, Tableau, Grunt, Sublime Text, Basecamp, RabbitMQ, Gulp, Adobe Photoshop, GitHub, Mercurial, Mocha, WebStorm, Figma, Sentry, Google Analytics, Git, Amazon Connect


Object-oriented Programming (OOP), REST, Test-driven Development (TDD), Agile, Scrum, Continuous Integration (CI), Continuous Delivery (CD), Continuous Deployment, Search Engine Optimization (SEO)


AWS Lambda, Heroku, WordPress, Twilio, Docker, Meteor, Firebase, Amazon Web Services (AWS), Amazon EC2


MongoDB, Redis, Memcached, Amazon S3 (AWS S3), RethinkDB, Docker Cloud, Elasticsearch, MySQL, PostgreSQL, Amazon DynamoDB


Single-page Applications (SPA), Axios, Full-stack, Front-end, API Integration, SOAP, Serverless, Architecture, Chrome Extensions, Storybook, API Gateways

Industry Expertise

Web Design

2006 - 2011

Master's Degree in Mining Engineering

The Kryvyi Rih National University - Kryvyi Rih, Ukraine

MAY 2022 - MAY 2025

AWS Certified Cloud Practitioner

Amazon Web Services