• Cross-project consulting and imple­men­tation for the frontend archi­tecture using ReactJS for white label solutions. Development of a modern frontend stack to create a sustainable technology basis for the coming years.
• Technology stack: Turbo­Repo, PNPM, ReactJS, TypeS­cript, ReactForm-Hooks, Radix-UI, Vanil­la­Ex­tract, i18Next, Jotai, Framer-Motion, Story­book, Vite, ESLint, ... ...

• Development of a poten­tially large frontend appli­cation for machine monitoring based on ReactJS.
• Technical Challenges: Set-up of a mono reposi­tory, Inter­na­tio­na­li­za­tion, Theming (White Label), On-Premise Rollouts & Handling of massive amounts of data

• Archi­tec­tural respon­si­bility and lead of the frontend archi­tec­ture. Development of impro­vement proposals of the existing archi­tec­ture. Furthermore sketching and development of the archi­tecture for new develop­ments.
• Project workflows following SCRUM metho­do­logy, API-first develop­ment, REST inter­faces (Micro Services), project manage­ment, Git hosting and DevOps with Azure, user autho­ri­zation via Auth0, ...
• Intro­duction of end-to-end tests with Cypress (incl. initial setup in the project) up to a coverage of 70% of the code paths for the existing customer center and thus a safeguard regarding regres­sions of the following releases. Signi­ficant impro­ve­ments of code segments consi­dering the acces­si­bility from React Testing Library (ARIA, semantic markup, ...)
• Extension and mainte­nance of an in-house responsive library. Publishing of components in a private NPM repository (Azure). Intro­duction of semantic versioning and establis­hment of change­logs.
• Techno­logies used: React with TypeS­cript, Microsoft Azure hosting + CI, Jest with Testing Library, E2E and Smoke tests with Cypress, connection of micro services with SWR and data storage in Redux or via hooks and Immer in the component hierarchy, ...

Sebastian convinces with his deep expertise in frontend archi­tec­ture, tooling and React in parti­cular. At the same time, he commu­ni­cates honestly and moves every codebase forward with his exper­tise. Thank you very much, it was fun!

Sebastian works indepen­dently on all tasks that arise in the day-to-day project work. He is an autho­ri­tative expert in the frontend area and is always available with his know-how. When analyzing the frontend archi­tec­ture, he found quite a few sensible oppor­tu­nities for impro­vement and helped to pragma­ti­cally turn them into reality by applying best practices. His sugge­s­tions for solutions and contri­bu­tions to discus­sions are always elementary input.

• Expansion of the GraphQL service to include new resol­vers, the integration of a MySQL database and existing REST services.
• Archi­tec­tural impro­ve­ments of the GraphQL service regarding typing, use of Async/Await, testa­bi­lity, etc.
• Tooling impro­ve­ments of the GraphQL service regarding bundling, code watcher and linting.
• Code reviews and archi­tec­tural impro­vement for parts of the internal component library.
• Impro­ve­ments to the CI pipeline and internal workflows for greater developer efficiency.
• Techno­logies used: React, Apollo GraphQL Client/Server, Story­book, TypeS­cript, Jest, Testing Library, Webpack, ESLint

It was great to work with you. I will miss your compe­tence, foresight and our chats. Good luck and remember: You always see each other twice in life. That was a threat. :)

Thank you so much for your profes­sional efforts. You have moved the team forward in many ways with your support. It was an extra­or­dinary pleasure to work with you.

Thank you for supporting us so energe­ti­cally with our PACE projects. Your refreshing and honest way has made us aware of concept gaps at one point or another.

• Further development and extension of a web appli­cation for inter­active tracking of trucks with construction materials. Development of a heuristic to automa­ti­cally visually prepare truck routes and display them in the Google-Maps-based view.
• Intro­duction of a mono-repository in order to be able to develop all front-end appli­ca­tions and components efficiently together. Intro­duction of tooling to automate static hosting in Azure together with the Azure CDN via GitLab-CI This was also the repla­cement of the previous much slower Docker-based front-end solution.
• Intro­duction of a backend selector to dynami­cally select a backend from different environ­ments.
• Unifi­cation of the TypeS­cript confi­gu­ration and ESLint rules for a uniform tooling in the team. Support of the intro­duction of Cypress-based E2E tests. Successive conversion of the code base to TypeS­cript.
• Imple­men­tation of a massively revised Axios-based API client for REST-based commu­ni­cation with the backend.
• Intro­duction of automatic semantic versions for the front-end products and generation of changelogs for different deployment scena­rios. Integration of the Changelogs into the release management process and prepa­ration of data for dashboards to commu­nicate custo­mi­za­tions to the global business.
• Sparring partner for UX designers and lead developer to design and structure the UI frame­work. I helped to develop a common under­standing of good component struc­tures and to implement this under­standing into reality.
• Used techno­lo­gies: React (Redux, React Router, i18next, Hooks), Lerna, Prettier, ESLint, TypeS­cript, Azure Cloud, Jest, Cypress.

Thank you for all your efforts, Sebas­tian! And wow, I didn't even notice that we worked together for almost 1.5 years. There really is a very big gap that the team has to fill now, as you have added several important contri­bu­tions to our stack. You've built a very good reputation as a React expert on the team over time, and I felt that people really trust your advice deeply. I wish you all the best for your future path and may the code be with you. Always.

Thanks Sebas­tian. It was a pleasure to work with you and discuss the tiny but important details of modern web technology stacks. Together we were able to make a huge leap forward in the way we develop and publish our web appli­ca­tions. Your in-depth experience with React and the meaningful practices of web development have always been very much appre­ciated by me.

During our colla­bo­ration with Sebas­tian, my team and I witnessed how a knowled­geable and experi­enced person can provoke the minds of the entire team. He forced us to learn and generally to question more. Also, to learn in the right direction so that we could then find solutions ourselves. Giving the team workable solutions is valuable for sure, but teaching them how to think and solve the problem on our own is more benefi­cial. Apart from that, I have enjoyed Sebastian's company very much and appre­ciate how we have had the advantage of finding superior solutions to various complex problems together.

It was a pleasure to work with Sebas­tian. Our project benefited a lot from his longtime frontend know-how. Not only does he know ReactJS well, but he always has the overall system in view. That doesn't happen often. He is commu­ni­ca­tive, committed and open. I myself would like to work with him again and again and can only recommend him for further projects.

Sebastian is an excellent developer and much more a colleague and coach who develops high quality solutions with sharp preci­sion. Sebastian has advanced topics such as backend for frontend and frontend opera­tions and enriched our team with a number of tools. I wish him all the best and a lot of fun and success in his new team.

As a UX Designer, it is great to work with Sebas­tian. His user-centered mindset supported and challenged the team and me. He is curious and never afraid of leaving the comfort zone when that means aiming for quality. For sure a value for any company he colla­bo­rates with.

Sebastian is distinctive for clear and direct commu­ni­ca­tion; both in meetings and in the source code. For complex problems and requi­re­ments Sebastian seeks simple and sustainable solutions. In doing so, he uses his extensive experience from previous projects. In tooling he is up to date and follows new develop­ments in the industry with enthu­siasm.

• Conven­tions regarding folder structure and imple­men­tation structure in general.
• Handling assets in relation to React and places them in the folder struc­ture.
• Usage patterns for TypeS­cript typing and inter­action with server-side data models.
• Expla­na­tions regarding advan­tages and disadvan­tages of functional or class decla­ra­tions in React.
• Recom­men­da­tions for newslet­ters, video courses and confe­rences as further building blocks for induc­tion.
• Reducing the boiler­plate in Redux by using the Duck pattern.
• Conceptual consi­de­ra­tions regarding the possible use of GraphQL.

I had the pleasure of being mentored by Sebastian during a coaching for the setup of an React based enter­prise appli­cation in the healthcare sector. He is a passionate software devel­oper, clear in his commu­ni­cation and a productive partner to exchange thoughts. He has my highest recom­men­da­tion.

Thanks a lot Sebastian for our consulting session about HTML5/React related techno­logies in Freiburg. Your broad knowledge in the HTML5 universe is impres­sing. You gave us a lot of valuable recom­men­da­tions based on, and this is the most important, real practical experi­ence. Thanks! Stefan

• New development of an online shop with the goal of multi-brand support and use in an inter­na­tional environ­ment.
• Technology stack: TypeS­cript, React, Styled Components, Reach Router, GraphQL with Apollo, Webpack and more
• Intro­duction of the GraphQL orche­stration layer based on Apollo in the client and server + team mento­ring.
• Revision and optimi­zation of server-side rendering (SSR).
• Imple­men­tation of a modern code splitting solution based on Loadable Components
• Intro­duction of a JWT-based SSR-compliant user authen­ti­fi­ca­tion.
• Tooling impro­ve­ments with the use of threading and caching with Webpack.
• Conversion of the TypeS­cript tooling to Babel to optimize execution time (espe­cially in the HMR use case).
• Impro­vement of routing on the client side and imple­men­tation of preloading for various code splitted paths.

Sebastian is an always-involved, high-energy team member with invaluable experience around tools and web perfor­mance. With Sebastian on the team, we finally got a reliable SSR/HMR setup with a fun developer experi­ence. He made it easy for us to switch over to GraphQL. Above all, I enjoyed our conver­sa­tions and our technical exchange. For me perso­nally, Sebastian was a role model for staying calm and constructive in confron­ta­tional situa­tions. Thank you!

• New development of a media library for all ARD stations as a common platform.
• Technology stack: React v16 (React Router, Redux), GraphQL with Apollo, Webpack v4, Sass, Flowtype and more
• Supported devices of the new platform: Modern HBBTV-capable televi­sions, responsive layouts for web browsers on mobile phones, tablets and desktops.
• Development and optimi­zation of the GraphQL interface with regard to commu­ni­cation with REST APIs.

• New development of a web-based dashboard with e.g. real-time departure infor­mation for use in the public transport environ­ment.
• Self-responsible archi­tecture and development in consul­tation with product managers. Selection of current techno­logies and training of employees in React and web develop­ment.
• Technology Stack: React v16 (Formik, Popmotion/Pose, React Intl, Reach Router,...), DotEnv, Webpack v4, Code Split­ting, Babel v7, Edge Platform, PostCSS, CSS Modules, CSS Grid, Story­book, Jest, ESlint, Stylelint, Prettier and more.
• Development of a GraphQL server with Apollo using a variety of different REST APIs (in-house and exter­nally).
• Detection of geo-position and deter­mi­nation of routes and distances using MapBox and OpenStreetMap.
• Page layout and imple­men­tation of the first design concepts in reusable components and views.

• Support in the development of a platform already used by custo­mers.
• Distri­buted team with offices in Leipzig and Munich.
• Sugge­sting Archi­tec­tural impro­ve­ments and mentoring of collea­gues.
• Technology Stack: React, Redux, Redux-Saga, Webpack, Babel, Less, ESlint, Karma, Mocha, Sinon, AWS, S3

Sebastian Werner joined a highly sophi­sti­cated and techni­cally complex project in a late project phase. After a very short training period, he not only worked as a full-fledged team member, but also offered constructive advice on solving archi­tec­tural and technical problems. We are very impressed with the coope­ration and look forward to imple­menting future projects together.

Sebastian Werner's main tasks were the imple­men­tation of forms and inter­ac­tions in the booking modules. and perfor­mance optimi­za­tions in chat and generally in terms of load time. The tasks assigned to him were handled to our complete satis­faction by Mr. Werner. With a great deal of dedication and his commu­ni­cative manner, Mr. Werner quickly made a name for himself in the development team and was able to make a major contri­bution to the success of the project.

• Project setup for a Green Field React appli­cation in the pharma­ceu­tical sector.
• Restruc­turing of the existing component library.
• Intro­duction of own NPM reposi­tories to increase the reuse of components, linting rules, etc.
• Responsive design with CSS grid layout and sensitive typography to cover the full range of devices.
• Server-side rendering with React v16 with an super smart code splitting logic for both JavaS­cript and CSS.
• Evaluation and selection of user interface components for anima­tion, charting,...
• Technology Stack: React, Redux, Webpack, Story­book, Edge Platform, ESlint, Stylelint, Prettier

Sebastian did a great job as a Frontend Engineer and Architect in our team. He happily shared his knowledge and teached us how to write state-of-the-art React appli­ca­tions. Thanks for the good colla­bo­ra­tion, it was a pleasure working together!

Sebastian's expertise in modern web techno­logies is compre­hensive and deep, so the colla­bo­ration has been an enriching experience for me. The customer also benefited from his invol­vement in various open source projects, which helped us to implement the requi­re­ments.

I worked with Sebastian on a new platform for Coliquio. His knowledge and expertise in javas­cript, React technology and modern front-end frame­works was really impres­sive. I'm looking forward to work with him again!

• Building a frontend archi­tecture in coope­ration with system archi­tects and product managers.
• Training, mentoring and code accep­tance (Git-Flow + pull requests) for 2 offshore teams in India.
• Technology evaluation for new technology stack in coope­ration with various stake­holders throughout the group.
• Analysis and conception of a new development 2.0 environment to improve the produc­tivity of software devel­opers.
• Technology Stack: React, Redux, Webpack, ESlint, Stylelint. Data connection via REST to backend layer.

I have worked with Sebastian in an agile project for an enter­prise in the banking segment. He is an excep­tio­nally talented frontend architect and react developer with a very deep under­standing of UX/UI. Sebastian has a personal passion to create state of the art web and mobile appli­ca­tions. His ability to pick up new technology is far beyond average. He never looks for the comfor­table approach, he challenged the design, the user experi­ence, how we work, how we produce software, which techno­logies to choose and will go way beyond the customers expec­tation to develop the best product. I would be thrilled to work with him in future projects!

I had the pleasure of working with Sebastian thru his leadership of a backbone-team at a client which both of us serve. Sebastian's dedication to driving an innovation agenda, through his personal identity as well as profound software skills, into our client's enter­prise archi­tecture was paramount, and yielded some great results. Sebastian is leading by example thru his daily worklife and was therefore encou­raging not only his very backbone-team but the project team itself. I would love the chance to colla­borate in the future again if the oppor­tunity was there.

It was a great privilege for me to work with such a talented and knowled­geable developer who is fluent in the latest UI tech like Sebas­tian. It is quite hard nowadays to find a passionate coder like him. We've learned a lot from his experience in React, Webpack and his EdgeStack during our last project. I'm looking forward to work with Sebastian again in the near future.

• Archi­tecture analysis and optimi­zation of the existing front end
• Development and archi­tecture in the React environment with other techno­logies such as Gulp, Webpack, ESLint, StyleLint, PostCSS, CSS Modules, etc.
• Intro­duction of Apollo Client + Server for using GraphQL for efficient commu­ni­cation between frontend and backend.

Perhaps you know this too: there are projects that simply don't run well - partly because of the fact that the best approach has not been followed in techno­lo­gical terms, because of high time pressure, lack of experience and not least because there is currently a parti­cu­larly high dynamic of competing approaches in the React environ­ment. Such a project needs expert knowledge and the persuasive stead­fastness that a better approach is possible, even if it throws the development back. Sebastian Werner has both compe­tence and perso­nality and, after a detailed analysis with the right concepts, steered the project in a much better way. A signi­fi­cantly leaner archi­tec­ture, improved tooling and the use of suitable libraries were the keys to success. We have learned a lot and thank you for your support - it was fun!

Sebastian was able to solve many problems with his expertise and give the project a good struc­ture. We were more efficient and effective thanks to the tools and archi­tecture he presented. He was also able to impart a lot of new knowledge to us. He has quickly established himself as a mentor, in addition to the role of the archi­tect, who has helped us to program better and more robust JavaS­cript code. I could learn a lot and was happy about his sugge­s­tions for impro­ve­ment. With the help of Sebas­tian, we were able to get a clear view of the real problem in some stalled situa­tions, which we were able to solve together as a team. I would have liked to have Sebastian in the project from the very begin­ning, in order to build up the project robust and stable with him.

Sebastian has exten­sive, up-to-the-minute knowledge of all aspects of developing highly complex web frontends. With the help of this knowledge, he has made a decisive contri­bution to the upcoming conversion of the frontend into a software that is in line with the current very fast-moving state of the art. The result was a solution that was recognized by the frontend team as outstan­ding. I can unreser­vedly recommend Sebastian as a frontend archi­tect, big-picture person and team player.

Sebastian is an experi­enced frontend technology consul­tant. He is distin­guished by his broad, as well as deep and above all current knowledge of state-of-the-art techno­lo­gies. We have therefore benefited greatly from his support and expertise in imple­menting the frontend with React-Redux-GraphQL for an inter­na­tio­nally oriented platform. We have experi­enced Sebastian as an active consul­tant, who does not shy away from putting his finger in the proverbial wound where necessary. He is always constructive and his sugge­s­tions help to raise the product to an improved level.

• Conversion of the styling platform to PostCSS.
• Development of the tooling solution with HMR for React Universal.
• Techno­lo­gies: Universal React + Redux, React-Intl for inter­na­tio­na­li­za­tion, ES2015+, PostCSS, Webpack v2 (use of tree-shaking, automatic chunks, ...)
• Target platforms: desktop browser, tablet browser, smart­phone browser

• Consulting front-end archi­tecture for a new inter­na­tional investment platform. The requi­re­ments were in the following areas: SPA (Single Page Appli­ca­tion), live updated charts and inter­na­tionally formatted values (curren­cies, etc.).
• Set up the project structure with Gulp as task manager, NPM for organizing the build environ­ment, JSPM as package management for frontend packages with ES2015 support, Sass for styles­heets and VueJS for inter­active functio­na­lities and component develop­ment.

Sebastian Werner works very conscien­tiously and accura­tely. He has an immense overview of front-end techno­logies and knows both the benefits and disad­van­tages of common approa­ches, tools and frame­works. Sebastian analyzes the processes and inter­ac­tions between front-end and user very preci­sely. This enables weaknesses in the UI concepts to be addressed and elimi­nated at an early stage. The front-end archi­tecture created in the project created a consi­de­rable added value and clear struc­tures which proved to be a very solid basis in the later course of the project.

Sebastian Werner is a very experi­enced front-end developer and architect who also keeps an eye on the holistic view of the entire project. He brings his expertise to bear and deals with the issues. He is focused, conscien­tious and yet fast and was able to parti­cipate success­fully in the project.

• Consulting on software archi­tec­ture, best practices, testa­bility and perfor­mance.
• Intro­duction of a MVP-Concept for better modularity and structure of the code.
• Imple­men­tation of a sophi­sti­cated inter­active interface with advanced UI transi­tions using VelocityJS.
• Intensive work with Less for styling the inter­face.
• Use of the Huawei framework to commu­nicate with the set-top box.
• Agent between the offshore team and the onsite team for development and merging strate­gies.
• Development of tests (Unit tests and UI tests) using Jasmine and DalekJS.
• Code documen­tation using JSDuck.
• Tooling for development and deployment with Grunt.

Sebastian and I have worked in the same project for about 1.5 years now and I've come to know him as a person who has a very good knowledge of his field and is always keen on keeping up-to-date on the latest develop­ments - which is not an easy thing when technology advance as fast as it does in this business. Sebastian also show a willingness to think outside the box (to use an old cliché) and tries to figure out new, better and more efficient ways of doing things. He's also proven to have a good feel and consi­de­ration for the impact of his work on the end-user experi­ence. As a plus, he's also a nice and amendable person that I think would easily fit in with most teams.

Sebastian was part of our agile development team and I worked with him as a product owner. Sebastian is an excellent web appli­cation / UI devel­oper. He was one of our technical key UI archi­tects who defined the UI archi­tecture and build major elements of those UI elements. He is innova­tive, focuses on details and delivers solution.

Sebastian Werner does a great job in our project. He has very good development and consultant skills and brings in solutions idea to make our project successful.

I can recommend Sebastian as a person with great expertise and deep background of web archi­tecture and Frontend develop­ment. He is a thought leader in his field. As a innovative strategist he under­stands complex matters even when outside of his direct area of exper­tise. He shows all the time a lot of analy­tical capability and willingness for his both personal & profes­sional develop­ment. He is ambitious and smart. His open-minded approach could not be overe­sti­mated.

In a huge colla­bo­ration project I recognized Sebastian as a very skilled and qualified teammate. From a design perspective he served as a convergent bridge between design and technology and pushed the project to a higher level with his exper­tise.

I enjoyed the time to work together with Sebastian in a challenging project at Deutsche Telekom for our TV Delivery Devision. Sebastian has worked for us in a inter­na­tional team as UI Architekt and JavaScript/HTML Consul­tant. In our project we are focusing to build the new user interface for the product Entertain TV. His very high skills in web development was very helpful and Sebastian did a profes­sional job. Especially his work on some reusable user interface components was very impressive and helps our project and other teams at Deutsche Telekom a lot. Thank you for your work, I would like to work with you every time again.

• Integration and custo­mi­zation of Bootstrap-Frameworks.
• Narrow coope­ration with conception and design for the reali­zation of a response page at reference level.
• Marketing-effective, magazine like design was combined with a low-maintenance solution for holistic adaptation to various environ­ments (from 300-1440 pixels in horizontal resolu­tion)
• Typogra­phi­cally highly sophi­sti­cated imple­men­tation using Modular Scales, Baseline Grids and adaptive column layouts for small and large elements.
• Imple­men­tation of a sticky-JavaScript-component for the stickyness of navigation and marketing areas.
• Development of an inter­active tabular product compa­rison based on an HTML table.
• Tooling for the delivery of the frontend via Jasy, Sass and Uglify. Image Optimi­zation with Image­Optim.

Sebastian is a highly motivated, intensive thinking and creative devel­oper. He has integrated well into the team and enriched the meetings with many ideas and innovative solutions. In addition, working with him was fun because he fit well into the team.

• Imple­men­tation of Photoshop designs with HTML5 technology for iPhone and Android-based devices.
• High perfor­mance RIA with inter­active layer alter­nation without classic page loading effect.
• MVP-based archi­tecture with template rendering based on Core-Framework.
• HTML5 form validation with inter­active feedback of error states.
• Connection to existing PHP-based backend via RPC.
• Integration of adver­tising and tracking networks via intel­ligent downstream integra­tion.

• RIA-application for setting VOIP-features for the fixed network connec­tion.
• Focus on the possi­bi­lities of modern desktop browsers (IE9+).
• Connection of an existing backend system with a REST-Proxy.
• Live-feedback and HTML5form validation in combi­nation with background synchro­ni­za­tion.
• MVP-based archi­tecture with template rendering based on Core-Frameworks
• Deployment and tooling based on Jasy for Windows, Mac and Linux.
• DOM manipu­lation and event handling using jQuery.

Sebastian was the driving force making our SCRUM Team successful. His strong programming skills combined with a keen perception helped us, to release a web appli­cation for telephony confi­gu­ration using state of the art web techno­lo­gies. Sebastian is a great guy with an enormous knowledge about modern software design and software archi­tec­ture. I really enjoyed working with him!

Sebastian Werner proves his first-class qualities in the development of RIA surfaces and is an excellent sparring partner in complex SCRUM projects.

• Archi­tecture and development of a hardware-accelerated scroller to navigate fast on large playing fields. Independent imple­men­tation that can be used for both DOM elements and canvas rende­ring.
• Use a pre-implemented animation class with handling for dropped frames and a clean render loop.
• Accurate imitation of iOS behavior with smooth accele­ration and bouncing (touch opera­tion).

Sebastian is a rare talent, and having him become part of our team has payed off in more than just one way. He has a unique talent to discover how a feature ideally *should* work, instead of imple­menting what others have told him, and thus improves the whole feature. He also often serves a voice of reason within heated developer arguments and under­stands the whole picture of an archi­tec­ture. One of the things I and Sebastian have in common that is rare to find in devel­opers is the eye for visual finish and user experi­ence. It is very rare to find a senior JavaS­cript developer who can do large-scale archi­tec­tural work, but also have enough artistic sense to rate the UX of an appli­ca­tion. He appre­ciates the little details that PMs often don't see, but consumers definitely will.

• Conception and imple­men­tation of an API browser that uses very efficient metadata in comments to generate a good documen­tation based on the source code. Comments can be written in Markdown and use Syntax-Highlighting for code.
• Scaffolding for easy creation of new appli­ca­tions based on Jasy (and optio­nally Core)
• Integration of a local web server based on CherryPy with support for proxying remote URLs (by-passing cross-domain problems during develop­ment).
• Connection of Jasy to Zynga's asset management infra­structure (via Amazon S3/Cloud­front). This enabled game devel­opers to manage assets in the global system and use them locally in the game as usual.
• Integration of a SpriteSheet generator with optional packing algorithms incl. of the necessary client-side methods in Core for using the images.
• Integration of TravisCI for automatic testing of the current version.
• General support for JSON or YAML as confi­gu­ration language.
• Impro­ve­ments in cross-system compa­ti­bility and integration of a "Jasy Doctor" to check the system to make sure every­thing is installed properly.

Working with Sebastian was always a pleasure. He has a vastly-founded knowledge about UI archi­tec­tures and compiling archi­tec­tures in JavaS­cript. He founded the Jasy project, which is the under­lying web framework at Zynga allowing to publish every­thing automa­gi­cally to S3 et al. Very talented guy, would love to work with him again.

• Polyfills for all ES5-methods and APIs.
• Development of multi-value properties (Setter/Getter) to correctly support fallback values for proper­ties.
• Imple­men­tation of script, style sheet and image loading systems based on the conceptual groundwork of LabJS.

I have had great experi­ences colla­bo­rating with Sebastian on various projects. I have used his software and tools exten­sively and found him eager to listen to feedback and make changes accor­dingly. He never hesitates to answer questions perso­nally. I appre­ciate his archi­tecture choices because they are forward-thinking, maintainable, and exten­sible.

• Employing with the future of the mobile commu­ni­ca­tions market and establishing web techno­logies to solve Deutsche Telekom's multi-platform approach.
• Development of the fussball.de Fan App (Demo video at Youtube) using Unify and PhoneGap.

Developer with excellent skills in web techno­lo­gies, always ahead with technology and market trends. Great guy.

I was very happy to work with Sebas­tian. He is a real expert in JavaS­cript and Python. But it can also be convincing in terms of UI/UX. I could learn a lot from him and I would like to work with him again at any time.

• Development of a general navigation logic for mobile appli­ca­tions and prepa­ration of patent appli­ca­tions for the created solutions.
• Basic work for integrating Unify into native appli­ca­tions using PhoneGap, QtWebkit and Adobe AIR.
• Intro­duction of the framework to internal and external events.
• Coope­ration with T-Labs, T-Mobile and other mobile phone providers and manufac­turers to integrate Unify into BONDI-Initiative or WAC.

Sebastian is a smart Web 2.0 guy, I worked together the last year. He is deeply involved in Browser, JavaS­cript, CSS, HTML techno­logies and always knows about the latest development and trends. I can recommend working together with him and enjoy common time and work.

• Development of a RIA appli­cation based on qooxdoo framework for reading books and managing subscrip­tions.
• Parsing and editing ePub based books including decryption and rendering within the appli­ca­tion.
• Imple­men­tation of a complex animation mechanism for qooxdoo-based appli­ca­tions and a custom theme based on the internal style guide.

Mentor, team leader and an excellent devel­oper.

Working with Sebastian was a big pleasure. He has brilliant ideas all the time based on his experience and huge development knowledge. He put to our work great dose of organi­zation and he has immense influence on code quality in our appli­ca­tion. I'm still impressed by his knowledge about frame­works, JavaS­cript and Python develop­ment.

• Head of four front-end specia­lists to develop innovative inter­faces and dialogues in one of the largest European social networks for pupils, students and adults.
• Redeve­lopment and impro­vement of existing interface components. Among other things, a photo viewer with the possi­bility to mark people.

Sebastian has extensive knowledge in his field, and is always able to adapt newest technical develop­ments to the benefit of the product he is working on. Using those skills to the fullest, he helped improve our product signi­fi­cantly.

• Development of a widget system taking into account many ideas of native UI toolkits such as Qt: Layout queues, child / shadow widgets, invali­dation and queuing of changes, styling of the new generation with shadows, dynamic decora­tors, color gradi­ents, etc.
• Python-based and cross-system version of the tooling solution has been developed. This makes it now possible to merge, optimize and inter­na­tio­nalize even the most complex appli­ca­tions for delivery.
• Inter­na­tio­na­li­zation and trans­lation of appli­ca­tions based on CLDR database and Gettext-inspired methods and data formats (PO files).
• Imple­men­tation of object-oriented patterns for classes and inter­faces like in Java and mixins like in Ruby.

I have been using qooxdoo for external and internal projects for a while. Sebastian has always been extremely helpful and accomo­dating when answering questions about qooxdoo and accepting contri­bu­tions. His direct, to-the-point and pragmatic style is an excellent asset.

I know Sebastian through his work on the qooxdoo library which is the coolest thing I have seen in a long time.

I worked with Sebastian during development of an open source software project which relies on the qooxdoo JavaS­cript GUI toolkit developed at Sebastian's company. His fast, competent and friendly support on every aspect of the toolkit was crucial for the successful development of my appli­ca­tion. I can recommend him as colla­bo­rator in open source and other projects, and his leading role in the qooxdoo project was clearly visible.

Sebastian is a visionary who has the unique ability to put his extra­or­dinary vision into practice. Sebastian's work on the qooxdoo toolkit provided capabi­lities and insight that no other toolkit has matched. His ability to combine perfor­mance, power, and ease of use is truly a welcome sight. There is no doubt that he will continue to be a driving force in the industry.

Sebastian ranks among the most influ­ential people in the Web 2.0 space. Sebastian's ingenious work on the archi­tecture of the qooxdoo framework has resulted in a fully functional and easy-to-deploy open source JavaS­cript UI. The Open Source Ajax community is indebted to Sebastian for his awesome work on qooxdoo.

• Design of the online presence, the order process and newsletter campaigns. Imple­men­tation of HTML markup and CSS layouts.
• Coope­ration with backend devel­opers to dynamize the content. XSLT templates for displaying product compa­ri­sons, product pages, etc. using Pustefix framework (Recursive XSLT engine)
• Imple­men­tation of JavaS­cript components for Control-Center: Toolbars, menus, toggle switches, etc. which can be controlled via simple HTML attri­butes.

Long story short: Sebastian is a highly skilled JavaScript/DOM Scripting Magician with whom it always was/is a pleasure to work.

• Imple­men­tation of a database interface using Combit Address Manager. Development of suitable VBA macros for Word to create labels and mail merge letters.
• Creation of the self-help newspaper using Adobe InDesign 1.5.. Coordi­nation with the print shop regarding the embedding of fonts and the reali­zation of colour fidelity. Intro­duction of an employee into the use of the software and creation of a first issue of the magazine.
• Creation of the homepage. Content could be easily custo­mized by employees as XML files. Imple­men­tation of a dynamic menu system based on Flash. Training of the team and creation of documen­tation for the mainte­nance of homepage contents.