Kostya Belenkii
Verified Expert in Engineering
Senior Front-end Developer
Nahariyya, Israel
Toptal member since June 18, 2020
Kostya is a senior front-end developer with nine years of experience, and he has developed web applications for more than a decade. As a highly skilled web engineer and consultant, he has led teams to deliver complex projects in diverse agile environments. Kostya blends his scientific background with his passion for building and enhancing products that have a positive impact on people.
Portfolio
Experience
- HTML - 12 years
- Agile Software Development - 11 years
- JavaScript - 10 years
- CSS - 10 years
- React - 8 years
- Unit Testing - 6 years
- TypeScript - 4 years
- Next.js - 2 years
Availability
Preferred Environment
Google Drive, Slack, Trello, Terminal, Visual Studio Code (VS Code), MacOS, Git
The most amazing...
...project I've completed was the front end of a SaaS system for cybersecurity analysts where I built and led a distributed team in a startup environment.
Work Experience
Leading Front-end Developer
Covver tech Ltd
- Architected reusable UI component library infrastructure, including automated visual regression testing.
- Developed multiple rich single-page apps from scratch in close connection with the product team. Led a team of front-end developers to bootstrap the initial version.
- Set up client-side monitoring (both product and technical) and A/B testing infrastructure.
Principal Web Developer
Airmeet
- Led a front-end team to develop one of the biggest modules, a contextual sidebar containing an event feed, messaging, notifications, and user and access management features.
- Took part in front-end performance analysis and optimization and solving the app scaling problems.
- Coached the team to execute Agile development processes and to use the Clubhouse project management tool efficiently.
Senior Front-end Developer
500Tech
- Developed several diverse projects from scratch, using JavaScript and React. I played different roles in each project, ranging from a one-month contract developer to the lead developer for a large-scale project.
- Participated in many projects as a senior developer, handling project planning, infrastructure, technical design, and team mentoring.
- Contributed to large enterprise and startup projects, using GraphQL, React Native, and TypeScript.
- Delivered presentations on React/Redux internally and at local meetup groups.
Front-end Team Leader
CyberInt
- Built and led a team of five remote developers to build a rich, single page application from scratch within a very tight deadline. We maintained this application for two years with a tested and highly reusable codebase.
- Participated in an R&D process optimization and helped others improve their organizational skills.
- Led open source initiatives in the company by publishing packages on npm and GitHub.
- Took part in organizing and speaking at a local React/Redux meetup group.
Front-end Web Developer
Magora Systems
- Improved and maintained a rich web route-planning application using vanilla JS and SVG.
- Developed a midsize web application from scratch using AngularJS.
- Improved performance of an SVG-based timeline module, enabling the ability to increase the number of supported elements by more than 10x.
Full-stack Web Developer
Code Your Dream
- Implemented and maintained a web platform that allowed users to create, share, and collaborate on slide presentations.
- Deployed and maintained a personality test platform that included the ability to create questionnaires based on the mathematical formulas that analyzed user responses.
- Participated in many diverse full-stack projects, contributing to all technical stages, from requirements analysis to deployment.
Experience
Lumigo
https://lumigo.io/product/Platform for Cybersecurity Analysts
https://blog.cyberint.com/introducing-argos-2.0We used React, Redux, and functional programming approaches, allowing us to reuse code pretty easily. This, in turn, allowed us to build a flexible, scalable, and maintainable UI for data analysts that supports a large number of tabs inside the application to hold all the necessary information in one place.
One of our biggest successes was shipping the first release very quickly as a result of hiring a distributed freelance team and using a straight development process.
Platform to Host Virtual Conferences
https://www.airmeet.com/Education
Master's Degree in Computer Science
Novosibirsk State University - Novosibirsk, Russia
Bachelor's Degree in Computer Science
Novosibirsk State University - Novosibirsk, Russia
Skills
Libraries/APIs
React, REST APIs, AWS Amplify, Node.js, Ramda, Firebase Web SDK
Tools
Git, Webpack, GitHub, FullStory, Sentry, React Apollo, Terminal, Trello, Slack, Jira, Clubhouse
Languages
JavaScript, CSS, HTML, GraphQL, TypeScript, PHP, SQL, Sass
Frameworks
Redux, Jest, AngularJS, Next.js, React Native
Paradigms
Unit Testing, Agile Software Development, Functional Programming
Platforms
Drupal, Linux, Amazon Web Services (AWS), MacOS, Firebase, Visual Studio Code (VS Code), Vercel
Industry Expertise
Cybersecurity
Other
Styled-components, Front-end, User Interface (UI), Storybook, Styled System, Team Leadership, A/B Testing, Apollo, Apollo Server, Google Drive, Enzyme, Computer Science, SaaS, Machine Learning, UI Animation
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
Share your needs
Choose your talent
Start your risk-free talent trial
Top talent is in high demand.
Start hiring