Stefan D.
Frontend Developer
Experience
Frontend Developer – sports event and city portal projects
München Betriebs GmbH
Development of an accessible, responsive website based on Figma designs for a major sports event in compliance with WCAG, BITV and EN 301 549.
Technical planning and setup of the toolstack with Vite, Playwright, Docker and GitLab CI.
Collaboration on two existing projects (Vue.js & Nuxt), focusing on bug fixing, accessibility audits and developing new features.
Working with design and QA to consistently implement accessible UI patterns.
Consulting on improving existing frontend architectures in terms of accessibility, performance and maintainability.
Tech Stack & Tools: Vue.js, Nuxt, JavaScript, HTML, CSS, Vite, Playwright, GitLab CI, Docker, WCAG 2.1, BITV, EN 301 549, Figma, Responsive Design, E2E-Testing, Accessibility Audits
Lead Developer for the Accessible Component Library "KoliBri"
ITZBund
Developing and maintaining accessible web components with Stencil and TypeScript according to WCAG, BITV and EN 301 549.
Refactoring and API optimization to improve developer experience and reusability.
Building and maintaining cross-component theming systems based on design specifications (Design Tokens, Custom Properties).
Enhancing and integrating internal React applications using KoliBri.
Designing and developing a reusable framework for visual regression testing of components and themes.
Setting up a monorepo with pnpm workspaces to optimize build and development processes.
Establishing CI/CD workflows with GitHub Actions and implementing automated testing and release pipelines.
Introducing Playwright as the E2E-Testing standard in the project.
Technical leadership of the development team, including mentoring, code reviews and architecture decisions.
Tech Stack & Tools: TypeScript, HTML, CSS, Stencil.js, React, Formik, Playwright, Jest, Node.js, Next.js, pnpm, Vite, GitHub Actions, WCAG 2.1, BITV, EN 301 549, Axe, NVDA, VoiceOver, Design Tokens, Visual Regression Testing
Deputy Frontend Team Lead
CHECK24 Vergleichsportal Baufinanzierung GmbH
Deputy Frontend Team Lead: April 2020 – June 2023
Senior Frontend Developer: October 2018 – March 2020
Frontend Developer: September 2016 – September 2018
Development and scaling of internal and customer-facing web applications with Vue.js, Nuxt, TypeScript and AngularJS as well as Java and Spring Boot in the backend.
Technical leadership of feature teams and deputy team leadership focusing on quality assurance, mentoring and process improvement.
Architecture responsibility within the frontend team: making decisions on technologies, modularization and shared standards to ensure a sustainable codebase.
Leading a new website project (Node.js, Express, Nuxt) with a focus on performance – reducing load times by about 90% through targeted code splitting, lazy loading and optimized caching.
Setting up a universal build and test system with Webpack, Jest and npm scripts for all frontend projects.
Performance optimization of key pages to improve load times and Core Web Vitals.
Developing a Node.js microservice with Puppeteer for automated PDF generation.
Enhancing an internal design system, including new components and integration into multiple applications.
Introducing and maintaining CI/CD pipelines with Jenkins in close collaboration with DevOps and backend (Java/Spring).
Developing a dashboard to monitor npm dependencies and automated upgrades.
Implementing linting, testing and error-tracking standards (ESLint, Stylelint, Sentry) across all projects.
Conducting technical interviews, performance reviews and supporting recruitment.
Tech Stack & Tools: TypeScript, JavaScript, HTML, CSS, Vue.js, Nuxt, AngularJS, Node.js, Express, Puppeteer, Java, Spring, Webpack, Gulp, Jest, Backstop.js, Jenkins, Sentry, Docker, REST, Microservices, npm, CI/CD, JIRA, Confluence, Bitbucket
Frontend Developer
SnipClip die digitale Fabrik GmbH
Developing interactive web applications, campaigns and communities integrating Facebook, SoundCloud and Instagram APIs.
Building a mobile web app with an offline-first approach and local caching for improved availability.
Designing and prototyping a native iPhone and Apple Watch app with Swift.
Creating a working prototype for a video chat application with WebRTC.
Introducing modern frontend toolchains (Gulp, Babel, Sass, Autoprefixer) to speed up development.
Migrating new projects from server-side rendering with jQuery to modern single-page applications with AngularJS.
Supporting backend development with PHP, Symfony and MariaDB and deploying on AWS/CloudControl.
Promoted to partner of the company due to outstanding performance.
Tech Stack & Tools: JavaScript, HTML, CSS, AngularJS, WebRTC, Swift, iOS/WatchOS, PHP, Symfony, MySQL/MariaDB, WordPress, Social Media APIs, Responsive Design, Offline First, Gulp, Babel, Docker, AWS, CloudControl
Apprenticeship as an IT Specialist in Application Development
Webmasterware.net GmbH
- Focus: web development with PHP, JavaScript, HTML/CSS
- Project work: developing a browser extension for syncing bookmarks within the team, including REST API and PHP/MySQL backend
Summary
Specialized in TypeScript, React, Vue.js and Node.js as well as accessible frontend architecture according to WCAG, BITV and EN 301 549. Experience in technical leadership, team mentoring and setting up sustainable DevOps and testing processes (CI/CD, GitHub Actions, Playwright). Combines deep technical know-how with a focus on developer experience, code quality and performance.
Languages
Education
Webmasterware.net GmbH
IT Specialist in Application Development, web development with PHP, JavaScript, HTML/CSS · Trier, Germany
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