Jozsef Varga, Developer in Budapest, Hungary
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Jozsef Varga

Bio

Jozsef is a confident software engineer with 15+ years of experience, specializing in modern front-end architecture. He’s highly proficient in TypeScript, React, and Node.js, and is known for his methodical, problem-solving mindset—often described as having a "detective’s" approach to engineering. Jozsef thrives in global, remote teams and brings clarity, precision, and reliability to every project.

Portfolio

Acrolinx
TypeScript, React, Node.js, CI/CD Pipelines, Webpack, Cypress, Vite, Jest...
Adverity
JavaScript, TypeScript, React, Redux, React Redux, Redux-Saga, Highcharts...
SICOM Systems
JavaScript, JavaScript Testing, Ext JS, Unit Testing, E2E Testing...

Experience

  • Software Architecture - 15 years
  • JavaScript - 15 years
  • Node.js - 12 years
  • E2E Testing - 8 years
  • Unit Testing - 8 years
  • TypeScript - 6 years
  • React - 6 years
  • Cypress - 3 years

Preferred Environment

Linux, Windows, Windows Subsystem for Linux (WSL), GitHub, Next.js

The most amazing...

...tool I've developed is a browser-based photobook editor built upon the Canvas API, capable of manipulating images in multiple ways.

Work Experience

Senior Front-end Developer

2023 - 2025
Acrolinx
  • Collaborated on an 8-person, cross-functional global team, operating within an Agile workflow using Kanban boards in Jira.
  • Worked closely with other teams, including site reliability, language engineers, and translators, to successfully deliver key product features.
  • Shaped the front-end architecture, guiding critical upgrades and modernizations, such as transitioning from Webpack to Vite and improving overall code maintainability.
  • Created a React-based component and utility library on top of Vite architecture with automated CI/CD, which deploys to npm and CDN. The library is used across four applications, directly boosting developer productivity.
  • Implemented a reusable client-side LaunchDarkly provider for practical feature flag usage. Optimized flag evaluations, leading to a 70% reduction in unnecessary checks and significant cost savings.
  • Developed robust user interfaces in React, focusing on optimizing rendering performance and ensuring accessibility standards. Optimized the user management UI, achieving a 5x performance improvement by preventing unnecessary renders.
  • Implemented a comprehensive testing strategy, including end-to-end and component tests with Cypress, unit tests with Jest, and Storybook stories for validation to ensure our test coverage exceeds 90%.
Technologies: TypeScript, React, Node.js, CI/CD Pipelines, Webpack, Cypress, Vite, Jest, E2E Testing, Unit Testing, Web Components, Component Testing, Storybook, APIs, Application State Management, Automated Testing, Agile, Software Architecture, Web Development, Software Engineering, Internationalization, i18n, Page Speed Optimization, CSS3, React Hooks, RESTFul APIs, UI Frameworks, Containerization, React Query, Figma to React, Zustand, Front-end Development, MySQL, Microservices, Docker, WCAG 2, Back-end, Lazy Loading, Front-end Architecture, Web Performance Optimization (WPO), Scalability, Accessibility, Web Accessibility, API Design, Testing, Microfrontends, API Integration

Senior Front-end Developer

2019 - 2022
Adverity
  • Developed modern React functional and reusable components as generic table components.
  • Implemented proper and reusable states with built-in Redux and React mechanisms.
  • Worked in various agile teams of 5–6 people with front-end and back-end developers, product managers, UX designers, and QA testers.
  • Built and configured various types of charts to visualize data.
  • Enhanced data calculation algorithms, doubling the speed and reducing the calculation time.
  • Implemented a mock service in Node.js, providing fake data for the client application.
  • Added a microservice that handled notification requests to be processed and forwarded to Slack and Microsoft Teams.
  • Transitioned legacy parts of the applications into modern, reusable components.
  • Collaborated closely with UI/UX designers and other departments.
Technologies: JavaScript, TypeScript, React, Redux, React Redux, Redux-Saga, Highcharts, Lodash, Remeda, Design Systems, Node.js, NPM, NestJS, MongoDB, PostgreSQL, Jest, Cypress, Storybook, Lerna, Webpack, ESLint, Monorepos, Unit Testing, Integration Testing, E2E Testing, CSS, Responsive UI, Single-page Applications (SPAs), APIs, Full-stack, REST APIs, Data Visualization, Web Applications, Agile, HTML, Front-end, Sass, HTML5, Data Engineering, Git, Tailwind CSS, REST, Puppeteer, ECMAScript (ES6), GitHub, Application State Management, Material UI, Reusable Libraries, Test-driven Development (TDD), Vite, Jira, Webhooks, JSON, CI/CD Pipelines, Software Architecture, Web Development, Software Engineering, Internationalization, i18n, Page Speed Optimization, CSS3, React Hooks, RESTFul APIs, UI Frameworks, React Query, Figma to React, Front-end Development, Microservices, Back-end, Lazy Loading, Front-end Architecture, Web Performance Optimization (WPO), Scalability, Accessibility, Web Accessibility, API Design, Testing, Microfrontends, API Integration

Senior Front-end Developer

2017 - 2019
SICOM Systems
  • Implemented Ext JS components for restaurant management and back office applications.
  • Collaborated closely with back-end engineers to deliver a suitable API contract.
  • Added multiple unit, end-to-end (E2E), and automated tests for Ext JS applications.
  • Managed the upgrade from Ext JS 5 to Ext JS 6, which required refactoring the components.
Technologies: JavaScript, JavaScript Testing, Ext JS, Unit Testing, E2E Testing, Automated Testing, CSS, Responsive UI, Single-page Applications (SPAs), APIs, Full-stack, REST APIs, Web Applications, Agile, HTML, Front-end, Sass, HTML5, Data Engineering, Git, REST, ECMAScript (ES6), Application State Management, Reusable Libraries, Test-driven Development (TDD), JSON, Software Architecture, Web Development, Software Engineering, CSS3, RESTFul APIs, UI Frameworks, Front-end Development, Back-end, Front-end Architecture, Testing, API Integration

Senior Front-end Developer

2015 - 2017
Avon Products
  • Implemented features in AngularJS for an Avon representative's application.
  • Collaborated with back-end engineers on API design.
  • Worked in various agile teams of 5–6 people with front-end and back-end developers, product managers, UX designers, and QA testers.
  • Enhanced the internal Grunt build tool to speed up multiple processes.
  • Mentored junior colleagues and helped them solve the onboarding challenges.
Technologies: JavaScript, AngularJS, Bootstrap, Lodash, Moment.js, Sass, Bower, Grunt, Gulp, Protractor, Karma, CSS, Responsive UI, Single-page Applications (SPAs), APIs, Full-stack, REST APIs, Web Applications, Agile, HTML, Front-end, HTML5, Data Engineering, Git, REST, ECMAScript (ES6), Application State Management, Reusable Libraries, Test-driven Development (TDD), JSON, Software Architecture, Web Development, Software Engineering, CSS3, RESTFul APIs, UI Frameworks, Front-end Development, Lazy Loading, Front-end Architecture, API Design, Testing, API Integration

Front-end Developer

2014 - 2015
Morgan Stanley
  • Added unit, automated, and E2E tests to the application.
  • Implemented features in Ext JS, from the Ext JS 4 to Ext JS 6 version.
  • Participated in the development of a common client framework.
  • Collaborated closely with back-end engineers and other departments.
Technologies: JavaScript, Ext JS, Node.js, Grunt, Unit Testing, E2E Testing, Automated Testing, Sencha Cmd, Sencha UI, Sencha Touch, CSS, Single-page Applications (SPAs), APIs, REST APIs, Web Applications, Agile, HTML, Front-end, Sass, HTML5, Git, REST, Application State Management, Reusable Libraries, JSON, Software Architecture, Web Development, Software Engineering, CSS3, RESTFul APIs, UI Frameworks, Front-end Development, Testing, API Integration

Front-end Developer

2013 - 2014
EPAM Systems
  • Implemented features in Ext JS in a secure environment.
  • Fixed various bugs in the front-end part of the system.
  • Worked in an agile team of six people with front-end and back-end developers and QA testers.
Technologies: JavaScript, Ext JS, CSS, Single-page Applications (SPAs), APIs, REST APIs, Web Applications, HTML, Front-end, HTML5, Git, REST, Application State Management, Reusable Libraries, JSON, Software Architecture, Web Development, Software Engineering, CSS3, RESTFul APIs, UI Frameworks, Front-end Development, API Integration

Front-end Developer

2012 - 2013
MadTatu LLC
  • Developed a Canvas-based photobook editor with jQuery and native JavaScript.
  • Collaborated closely with the design team to be able to parse photobook templates.
  • Worked with different browser APIs and cross-browser functionalities.
Technologies: JavaScript, Canvas, jQuery, jQuery UI, SVG, CSS, Single-page Applications (SPAs), APIs, SQL, Full-stack, REST APIs, Web Applications, HTML, Front-end, Sass, HTML5, Git, LAMP, REST, Application State Management, Reusable Libraries, JSON, Software Architecture, Web Development, Software Engineering, CSS3, RESTFul APIs, UI Frameworks, Front-end Development, MySQL, Back-end, API Design, API Integration

Experience

Adverity

https://www.adverity.com/
Adverity is an integrated data platform enabling marketing, sales, and eCommerce teams to make better decisions and improve performance. I took part in the development of their two major products as a senior front-end developer.

Dice Wars

This project was my university thesis project. It is a multiplayer browser-based game built entirely on the Canvas API, where players are scattered around a hexagon-tiled map to occupy the most tiles by rolling dice in a turn-based style. The communication between players was achieved using the WebSocket API connected to a Node.js-based server.

Web-based Photo Book Editor

A Canvas API-based web application for creating photobooks easily with multiple templates, image editing capabilities, and much more. I led the project alone as a front-end developer and used mainly plain JavaScript.

Education

2004 - 2009

Bachelor's Degree in Software Engineer and Mathematics

Eötvös Loránd University - Budapest, Hungary

1999 - 2004

Technical Diploma in Computer Engineering

János Bolyai Technical School - Budapest, Hungary

Skills

Libraries/APIs

React, Node.js, REST APIs, React Redux, Highcharts, React Query, Redux-Saga, Lodash, Moment.js, jQuery, jQuery UI, Socket.IO, Puppeteer

Tools

NPM, Git, GitHub, Lerna, Webpack, JavaScript Testing, Bower, Grunt, Gulp, Karma, Sencha Cmd, Sencha UI, Canvas, Jira

Languages

JavaScript, TypeScript, HTML5, CSS3, CSS, HTML, ECMAScript (ES6), SQL, Sass

Paradigms

Unit Testing, E2E Testing, Testing, Agile, REST, Microservices, Web Performance Optimization (WPO), Microfrontends, Automated Testing, Scrum, Test-driven Development (TDD)

Storage

JSON, MySQL, Relational Databases, MongoDB, PostgreSQL

Frameworks

Redux, NestJS, Jest, Cypress, Ext JS, AngularJS, Bootstrap, Protractor, Sencha Touch, Express.js, Tailwind CSS, Material UI, Next.js

Platforms

Linux, Windows, LAMP, Docker

Other

Software Architecture, Single-page Applications (SPAs), APIs, Full-stack, Web Applications, Front-end, Application State Management, React Hooks, RESTFul APIs, UI Frameworks, Figma to React, Front-end Development, Front-end Architecture, API Integration, Data Visualization, Responsive UI, Data Engineering, Reusable Libraries, Vite, Internationalization, i18n, Page Speed Optimization, Zustand, Back-end, Lazy Loading, Scalability, Web Development, Software Engineering, Windows Subsystem for Linux (WSL), Algorithms, Mathematics, Design Systems, Storybook, ESLint, Monorepos, Integration Testing, SVG, WebSockets, Remeda, Webhooks, CI/CD Pipelines, Web Components, Component Testing, Containerization, WCAG 2, Accessibility, Web Accessibility, API Design

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