Freelancer profile Jonathan Weiß from Düsseldorf, Consultant Web Technologies | Profiles from freelancers and companies

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Jonathan Weiß, Consultant Web Technologies from Düsseldorf

Profileimage by Jonathan Weiss Consultant Web Technologies from Duesseldorf
Jonathan Weiß
Jonathan Weiß

Consultant Web Technologies

40591 Düsseldorf Freelancer in Germany

not available by 07/03/2017
Hourly-/Daily rates: Depending on the project requirements
Last update: 16.02.2017 07:34

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Language skills
German (first language)English (business fluent)

Abilities, knowledge, experiences of Jonathan Weiß

  • I am an expert in Web technologies: HTML5, CSS3, JavaScript.
  • I create the architecture for responsive, scalable and extendable front-ends that respect accessibility and perform great.
  • I believe that RWD is only the beginning and that every device soon will be able to display websites or run web apps.
  • I teach people how to use Web technologies and how to write beautiful code (by using methods like pair programming or code reviews).
  • I mediate between the special department and development by understanding and translating business requirements.

Web Frameworks
  • jQuery
  • qooxdoo (I have worked on qooxdoo as a core developer)
  • jQuery UI
  • Sencha Touch
  • Twitter Bootstrap
  • Knockout
  • Backbone.js
  • Rulus.Class

  • MySQL
  • MongoDB

Template languages
  • Smarty
  • Handlebars
  • JSP
  • Jade
  • Thymeleaf

Software Development Methods
  • Scrum
  • Kanban
  • Test Driven Development

References of Jonathan Weiß

My most recent projects are listed here. For a complete list, please have a look at my (German) freelancer profile document (PDF format).

Period: 03/2014 to 12/2014 - 9 months
Client: Etengo AG  – http://www.etengo.de
Customer: International Engineering Company
Role in project: Consultant, Developer

Development of frontend components
  • Creation of several new components
    • Implementation of Form Elements which reflect the CI of the customer
    • Creation of a module to validate forms
    • Building a module to display external content by respecting the content height
    • Realization of a module to display Google Maps
    • Implementation of a controller for interactive, dynamic forms
  • Refactoring of a complex component from using a jQuery plugin into a JavaScript package with a clean class hierarchy using Rulus.Class.
  • Refactoring of existing components while maintaining existing functionality
  • Reworking of components considering
    • Coding Guidelines (all languages)
    • Test coverage in JavaScript
    • Visual regression tests
  • Implementation of graphical drafts while considering
    • Requirements of the responsive Design
    • Constraints in legacy browsers
    • Accessibility 
Optimization and improvement of the frontend architecture and build process
  • Introduction of visual regression tests using PhantomCSS
  • Further development of the existing coding standards
Documentation and coaching
  • Coaching about how to do cross device testing and debugging
  • Workshop about how to do visual regression testing
  • Creation of class diagrams and activity diagrams that display the new component for dynamic forms
Technologies used: HTML5, CSS3, Sass, JavaScript, jQuery, CSSModal, pickadate.js, git, JSON, grunt, bower, requireJS, PhantomJS, PhantomCSS, istanbul, jshint, scsslint, Confluence, JIRA, git, Selenium, Thymeleaf

Period: 01/2014 to 2/2014 - 2 months
Client: Sapient GmbH, Köln – http://www.sapient.com/de-de/sapientnitro.html
Customer: Italian eyewear brand
Role in project: Developer, coach

Further development of a responsive e-commerce frontend
  • Refactoring of existing UI modules
  • Implementation of jQuery plugins and page controllers
  • Support and coaching of the off-shore developers
  • Adjusting and extension of automated UI regression tests
Technologies used: HTML5, CSS3, LESS, JavaScript, jQuery, jQuery UI, XML, SVN, JSON, PhantomJS, JSP

Period: 07/2012 to 12/2013 — 6 months
Client: Tourismussuite GmbH, Neuss – http://www.tourismussuite.com
Customer: International hotel chain
Role in project: Architect and developer

Optimization and refactoring of an existing frontend architecture
  • Definition of success factors for a successful refactoring with the stakeholders
  • Analysis of the frontend processes, project structure and data models
  • Measurement of the frontend performance using defined key figures
  • SWOT-Analysis of the existing architecture by code inspection and interviews with project stakeholders
  • Documentation of the outcome in the enterprise wiki
  • Building a draft for the new frontend architecture and creating a strategy for continuous improvement
  • Coaching of the developers who participate in the implementation
Implementation of sub-projects
  • Refactoring and extending a booking process
  • Initiation of JavaScript modules using AMD and transfer of all libraries into modules
  • Automation of the build and deployment jobs using Grunt
  • Modernization and update of a hybrid mobile app to use PhoneGap 3
Technologies used: HTML, CSS, JavaScript, PhoneGap, Sencha Touch, Knockout, RequireJS, jsDuck, jQuery, jQuery UI Grunt, JRIA, Graphviz, git, XML, REST webservices, JSP, JSON

Location flexibility of Jonathan Weiß

Preferred in the region Rhein-Ruhr - but generally I am able to work in every part of Germany and parts of Switzerland.