Oliver Kišš, Developer in Brno, South Moravian Region, Czech Republic
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Oliver Kišš

Verified Expert  in Engineering

Software Developer

Brno, South Moravian Region, Czech Republic

Toptal member since September 7, 2020

Expertise
Front-endDashboardGitCSSJavaScriptReact.jsTypeScriptSvelteData VisualizationFull-stackBack-end DevelopersChrome Extension DevelopmentREST APINode.jsRedux
Bio

Oliver is a senior full-stack developer with over a decade of experience specializing in React and TypeScript. He excels at transforming complex codebases through strategic refactoring and building high-performance applications with measurable speed improvements. Whether optimizing slow systems or architecting scalable solutions, Oliver delivers elegant code that solves real business problems. His background as a quality engineer at Red Hat reinforced his commitment to stable, reliable products.

Portfolio

Labormex / H2 Organizer
TypeScript, Svelte, Cloudflare, Drizzle, SQL, HelloSign API, Node.js, tRPC...
Treat Technologies, Inc
React, Front-end, Webpack, React Router, React Hooks, Storybook, Material UI...
Private NDA Companies in Crypto, Social Media, Fintech
JavaScript, React, TypeScript, Next.js, Monorepos, Material UI, VictoryChart...

Experience

  • React - 7 years
  • Node.js - 4 years
  • TypeScript - 3 years
  • Next.js - 3 years
  • Tailwind CSS - 2 years
  • Chrome Extensions - 2 years
  • Svelte - 2 years
  • tRPC - 2 years

Availability

Full-time

Preferred Environment

Visual Studio Code (VS Code), MacOS

The most amazing...

...thing I've developed was a HelloSign integration that automated document processing and signatures, becoming essential to the company's core business.

Work Experience

Senior Full-stack Developer

2023 - PRESENT
Labormex / H2 Organizer
  • Developed a TypeScript and Svelte visa management system that streamlined application processing for agricultural workers.
  • Improved front-end accessibility by implementing keyboard navigation for all components.
  • Architected a robust HelloSign integration using Cloudflare back-end services that automated document workflows.
  • Integrated Google Maps API to visualize job locations, housing, and farms.
  • Worked as a core member of a transition from an external agency by auditing the codebase, refactoring, and establishing code standards.
Technologies: TypeScript, Svelte, Cloudflare, Drizzle, SQL, HelloSign API, Node.js, tRPC, Tailwind CSS, SQLite, API Integration, Google Maps, Figma, Monorepos, RESTFul APIs, Responsive Web Design (RWD), Prisma, CI/CD Pipelines, REST, Full-stack, Back-end

Front-end Developer

2022 - 2023
Treat Technologies, Inc
  • Developed critical features for a customer context platform using React with Material UI, improving user experience and addressing key client requirements.
  • Implemented a comprehensive testing strategy using Jest for unit tests and Storybook to prevent visual regressions during feature development.
  • Refactored existing components into a reusable library that accelerated the development of new features while ensuring consistent design patterns.
  • Optimized application performance by implementing code splitting and dependency management, significantly reducing initial load times.
  • Migrated build process from Webpack to Parcel, improving build times and increasing overall developer productivity.
  • Contributed to coding standards documentation that streamlined code reviews and improved consistency across the codebase.
Technologies: React, Front-end, Webpack, React Router, React Hooks, Storybook, Material UI, Jest, Next.js, Figma, RESTFul APIs, Responsive Web Design (RWD), REST

Senior UI Developer

2021 - 2022
Private NDA Companies in Crypto, Social Media, Fintech
  • Engineered a cryptocurrency exchange platform with real-time market data integration and visualization.
  • Implemented advanced trading visualizations, including market depth charts, liquidity simulation tools, and integrated TradingView for comprehensive market analysis.
  • Built a high-performance, SEO-optimized landing page using Next.js that effectively showcased platform features.
  • Implemented a monorepo architecture that streamlined development by sharing code between the web application and the browser extension, reducing maintenance overhead.
Technologies: JavaScript, React, TypeScript, Next.js, Monorepos, Material UI, VictoryChart, TradingView, CSS, Browser Plugins, HTML, Data Visualization, Dashboards, Webpack, Single-page Applications (SPAs), APIs, REST APIs, Git, Jest, Front-end, React Router, React Hooks, Charts, Chrome Extensions, Responsive Web Design (RWD), WebSockets, REST

Senior UI Developer

2020 - 2022
Private NDA Companies in Crypto, Social Media, Fintech
  • Engineered a browser extension that seamlessly integrated new features into Twitter's interface while maintaining performance and robustness during frequent platform UI changes.
  • Leveraged React Native and Expo to port selected features of the browser extension to mobile platforms.
  • Developed a sophisticated DOM manipulation system that reliably injected React components into Twitter's interface.
Technologies: React, Browser Plugins, Progressive Web Applications (PWAs), Material UI, React Native, TypeScript, Webpack, APIs, REST APIs, Jest, Front-end, React Router, Expo, Chrome Extensions, Responsive Web Design (RWD), REST, Full-stack, Back-end

Senior JavaScript Developer

2016 - 2020
Currys PC World
  • Built key components for a single-page application that streamlined the checkout process for thousands of daily customers on a major UK electronics retail site.
  • Implemented complex order fulfillment logic handling diverse delivery methods and product-specific journeys across physical and digital shopping channels.
  • Collaborated with cross-functional teams to integrate applications as micro-front ends, enabling improved code maintenance and independent deployment cycles.
  • Built a Node.js and NestJS development environment that simulated the production PHP back end, enabling the front-end team to work independently and accelerate feature delivery.
  • Developed reusable UI components that improved consistency across the customer journey while reducing development time for new checkout features.
  • Utilized Jira for ticket tracking, configured Bamboo for deployment pipelines, and incorporated Zeplin designs to ensure accurate implementation.
Technologies: Jest, Express.js, Styled-components, Redux, Node.js, React, JavaScript, CSS, TypeScript, HTML, Webpack, Single-page Applications (SPAs), APIs, REST APIs, Git, Front-end, Storybook, NestJS, RESTFul APIs, Responsive Web Design (RWD), CI/CD Pipelines, Agile, REST

JavaScript Developer

2015 - 2016
Opoint (later acquired by M-Brain)
  • Created a data visualization application, enabling journalists and analysts to search, categorize, and generate custom reports from thousands of news articles.
  • Diagnosed and fixed critical performance bottlenecks that improved search response time by 75% and enhanced overall application usability.
  • Built an internal annotation tool that streamlined the process of cataloging and analyzing news video content for media monitoring teams.
  • Implemented responsive design principles, ensuring consistent functionality across desktop and mobile browsers for the news search application.
Technologies: AngularJS, React, JavaScript, CSS, Angular, HTML, Data Visualization, Dashboards, Single-page Applications (SPAs), APIs, REST APIs, Git, Front-end, Charts, Responsive Web Design (RWD), REST

Quality Engineer

2011 - 2015
Red Hat
  • Developed comprehensive test suites using Java, Selenium, and JavaScript with Nightwatch.js.
  • Built reference applications utilizing diverse Java web frameworks to validate functionality and integration capabilities of enterprise middleware products.
  • Established automated continuous integration workflows in Jenkins.
  • Diagnosed complex test failures across distributed systems, identifying root causes and collaborating with developers to implement fixes.
Technologies: JavaScript, HTML, Git, Jenkins, Continuous Integration (CI), Java, Maven XML, CI/CD Pipelines, Agile

Experience

Time Zone Overlap Tool

https://timezones.oliverkiss.dev/
A web application written in Svelte allows users to calculate and see an overlap of working hours between different time zones.

I created this application for myself to help me see how my working hours fit the needs of different Toptal clients.

Currys PC World eCommerce site

http://www.currys.co.uk
I worked in the team responsible for the basket and checkout portion of this website as a front-end developer. The basket and later steps are a single page application written in React. It allows users to preview the products they are about to buy, select additional services, and choose how they want to receive or collect them. The same application is used as a micro-front end inside the application utilized by in-store colleagues.

Media Monitoring Portal

https://new.m-adaptive.com/
A web application used to search news articles, organize them in profiles, explore statistics related to profiles, and generate reports from them. I assisted as a front-end developer on this application.

Education

2012 - 2014

Coursework towards a Master's Degree in Computer Science

Masaryk University - Brno, Czech Republic

2008 - 2011

Bachelor's Degree in Computer Science

Masaryk University - Brno, Czech Republic

Skills

Libraries/APIs

React, Node.js, REST APIs, React Router, D3.js, Google APIs, Drizzle, HelloSign API, Google Maps

Tools

Git, Webpack, Jenkins, Figma, Expo, Prisma

Languages

JavaScript, CSS, TypeScript, HTML, SQL, Java

Frameworks

Material UI, Svelte, Redux, Jest, Next.js, tRPC, Tailwind CSS, Angular, Express.js, AngularJS, React Native, NestJS

Paradigms

Responsive Web Design (RWD), REST, Continuous Integration (CI), Agile

Platforms

Netlify

Storage

SQLite

Other

Dashboards, Single-page Applications (SPAs), APIs, Front-end, React Hooks, Styled-components, Browser Plugins, Data Visualization, Chrome Extensions, Charts, RESTFul APIs, WebSockets, CI/CD Pipelines, Full-stack, Back-end, Progressive Web Applications (PWAs), Monorepos, VictoryChart, TradingView, Computer Science, Biotechnology, Serverless, Storybook, Cloudflare, API Integration, Maven XML

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