Stefan D.-Frontend Developer
Check rate
Experience
Frontend Developer – Sports Event and City Portal Projects
München Betriebs GmbH
- Developed an accessible, responsive website based on Figma designs for a major sports event in compliance with WCAG, BITV and EN 301 549
- Planned and set up the tool stack with Vite, Playwright, Docker and GitLab CI
- Worked on two existing projects (Vue.js & Nuxt), focusing on bug fixing, accessibility audits and developing new features
- Collaborated with Design and QA to consistently implement accessible UI patterns
- Advised on improving existing frontend architectures in terms of accessibility, performance and maintainability
Lead Developer for Accessible Component Library “KoliBri”
ITZBund
- Developed and maintained accessible web components with Stencil and TypeScript according to WCAG, BITV and EN 301 549
- Refactored and optimized APIs to improve Developer Experience and reusability
- Built and maintained cross-component theming systems based on design specifications (Design Tokens, Custom Properties)
- Further developed and integrated internal React applications based on KoliBri
- Designed and developed a reusable framework for visual regression testing of components and themes
- Set up a monorepo with pnpm workspaces to optimize build and development processes
- Built CI/CD workflows with GitHub Actions and implemented automated test & release pipelines
- Introduced Playwright as the E2E testing standard in the project
- Provided technical leadership for the development team, including mentoring, code reviews and architectural decisions
Deputy Frontend Team Lead
CHECK24 Vergleichsportal Baufinanzierung GmbH
- Developed and scaled internal and customer-facing web applications with Vue.js, Nuxt, TypeScript and AngularJS, as well as Java and Spring Boot on the backend
- Provided technical leadership for feature teams and acted as deputy team lead, focusing on quality assurance, mentoring and improving team processes
- Held architectural responsibility within the frontend team: deciding on technologies, modularization and shared standards to ensure a sustainable codebase
- Led a new website project (Node.js, Express, Nuxt) with a focus on performance – reduced loading time by approx. 90% through targeted code splitting, lazy loading and optimized caching
- Built a universal build and testing system with Webpack, Jest and npm scripts for all frontend projects
- Optimized the performance of core pages to improve loading times and Core Web Vitals
- Developed a Node.js microservice with Puppeteer for automated PDF creation
- Further developed an internal design system, including new components and integration into multiple applications
- Introduced and maintained CI/CD pipelines with Jenkins in close collaboration with DevOps and Backend (Java/Spring)
- Developed a dashboard for monitoring npm dependencies and automated upgrades
- Implemented linting, testing and error tracking standards (ESLint, Stylelint, Sentry) across all projects
- Conducted technical interviews, performance reviews and supported recruiting
Frontend Developer
SnipClip die digitale Fabrik GmbH
- Developed interactive web applications, campaigns and communities with integrations of the Facebook, SoundCloud and Instagram APIs
- Built a mobile web app with an Offline First approach and local caching for improved availability
- Designed and prototyped a native iPhone and Apple Watch app with Swift
- Developed a working prototype for a video chat application with WebRTC
- Introduced modern frontend toolchains (Gulp, Babel, Sass, Autoprefixer) to increase development speed
- Migrated new projects from server-side rendering with jQuery to modern single-page applications with AngularJS
- Supported backend development with PHP, Symfony and MariaDB, as well as deployment on AWS/CloudControl
- Appointed as a shareholder of the company due to excellent performance
Industry experience
See where this freelancer has spent most of their professional time.
Experienced in Banking and Finance, Government and Administration, Information Technology, and Sport.
Business area experience
See which departments and functions this freelancer has contributed to most.
Experienced in Information Technology, Quality Assurance, Project Management, and Product Development.
Summary
Experienced Senior Fullstack Developer with over 10 years of professional experience developing modern web applications and accessible component libraries. Specialized in TypeScript, React, Vue.js and Node.js, as well as accessible frontend architecture according to WCAG, BITV and EN 301 549. Experienced in technical leadership, team mentoring and building sustainable DevOps and testing processes (CI/CD, GitHub Actions, Playwright). Combines deep technical expertise with a focus on Developer Experience, code quality and performance.
Skills
Frontend Development
- Typescript, Javascript, Html5, Css3, Scss
- Vue.Js, Nuxt, React, Redux, Stencil, Angularjs, Next.Js, Formik
- Responsive Design, Design Tokens, Theming, Accessibility (Wcag 2.1, Bitv, En 301 549, Nvda, Voiceover)
- Progressive Web Apps, Offline First
- Eslint, Stylelint, Sentry, Storybook, Lighthouse, Core Web Vitals
Backend Development
- Node.Js, Express, Java, Spring Boot
- Rest Apis, Microservices, Mysql, Mariadb, Oracle
Testing & Qa
- Jest, Vitest, Playwright, Backstop.Js, Axe
- E2e Testing, Visual Regression Testing, Tdd
Build & Devops
- Npm, Pnpm, Webpack, Vite
- Docker, Jenkins, Github Actions, Gitlab Ci
- Monorepos, Ci/Cd, Dependency Management
Methods & Collaboration
- Agile Software Development (Scrum, Kanban)
- Version Control With Git (Github, Gitlab, Bitbucket)
- Project And Knowledge Management: Jira, Confluence
- Code Reviews
Languages
Education
Webmasterware.net GmbH
IT Specialist for Application Development · Trier, Germany
Statistics
Experience
Global experience
Expertise
Qualifications
Profile
Frequently asked questions
Have questions? Find more information here.
Stefan is based in Berlin, Germany.
Stefan speaks the following languages: German (Native), English (Advanced).
Stefan has at least 13 years of experience. During this time, Stefan has worked in at least 4 different roles and for 4 different companies. The average length of individual experience is 3 years and 3 months. Note that Stefan may not have shared all experience and actually has more experience.
Based on recent experience, Stefan would be well-suited for roles such as: Frontend Developer – Sports Event and City Portal Projects, Lead Developer for Accessible Component Library “KoliBri”, Deputy Frontend Team Lead.
Stefan's most recent position is Frontend Developer – Sports Event and City Portal Projects at München Betriebs GmbH.
In recent years, Stefan has worked for München Betriebs GmbH, ITZBund, and CHECK24 Vergleichsportal Baufinanzierung GmbH.
Stefan is most experienced in industries like Banking and Finance, Government and Administration, and Information Technology. Stefan also has some experience in Sport.
Stefan is most experienced in business areas like Information Technology, Quality Assurance, and Project Management. Stefan also has some experience in Product Development.
Stefan has recently worked in industries like Banking and Finance, Government and Administration, and Sport.
Stefan has recently worked in business areas like Information Technology, Quality Assurance, and Project Management.
Stefan holds a Master in IT Specialist for Application Development from Webmasterware.net GmbH.
Stefan is immediately available full-time for suitable projects.
Daily rate distribution
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Average rates for similar positions
Rates are based on recent contracts and do not include FRATCH margin.
The average daily rate is the mean of all daily rates from recent contracts of comparable freelancers on our platform.
The median daily rate is the middle value of all daily rates — half of comparable freelancers charge less, half charge more. Unlike the average, it is barely affected by outliers.
Calculated based on our freelancers’ daily rates as of 17 Oct 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
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