Casper Jonker //.nl

Fullstack Developer


Welcome to my
Website Portfolio Curriculum Vitae

Momentarily I'm working as a Fullstack Developer at the NOS. In this role I busy myself with developing/maintaining the NOS editorial system called iNOS.


I do
Interaction Design Usability Tests Front-End Development

As an Interaction Designer I do not limit myself to creating wireframes. HTML, CSS, Javascript and the Adobe CS are part of my main tools.


I work Iterative

My method is dependent on the assignment. At the start of each assignment I compose an action plan.

In general I use an iterative design process.

Diagram iteratief ontwerpproces


  • Fullstack Developer
  • NOS
  • 2016-11-11

Fullstack Development at NOS

Momentarily I'm working as a Fullstack Developer at the NOS. In this role I busy myself with developing/maintaining the NOS editorial system called iNOS. Techniques I'm using are Javascript (Backbone) and PHP (Laravel).

Laravel logo    Image result for backbone logo


While here, I'm not only developing complex web applications and software systems. I'm also working on broadcast processes like video editing and complete studios.

regie nos

  • Front-end developer
  • The Valley
  • 2016-07-10

Front-End Development bij The Valley

From Octobre 2015 till July 2016 I have worked for three to five days a week to assist the front-end development team of The Valley. The Valley develops apps, corporate websites, webportals, (ad) campaigns, activations, events, content, e-commerce platforms, interiors, corporate identities, loyalty programs, CRM and email marketing. They do this for a number of very different big and small clients.

valley klanten2

On their website they describe it as: "We want to create meaningful and intuitive experiences that will impact the consumer and as a result will lead to affection and transaction. With our ecosystem of brand, experience and data we are able to create the ultimate brand experience through out the whole customer journey."

responsive mail4

During my time at The Valley I have mostly focused on e-mail, which is how I became an e-mail specialist. While building these e-mails in HTML I had a close collaboration with the e-mail marketeers who collaborated with the the clients. Some of these clients I did most of my work for are the BankGiro Loterij, ABN AMRO, KLM, Rabobank and Essent.

Logo LitmusLogo Tripolis

For e-mail I worked with programmes such as Tripolis and Litmus. Apart from e-mail I also did a number of other activities, such as the responsive website for Essent, animations for the ONVZ app. There is a chance I will be doing more work for The Valley whenever they are short of manpower.

Front-end developer Randy Fitz-Jim on my work at The Valley:

“Casper is a good teamplayer, it's fun to work with him and will most likely fit in any team. Casper works very precise and is willing to learn new techniques. Most of all he is a reliable person.”

  • Website
  • De Lancey Foundation
  • 2016-06-15

Website from scratch

The Foundation aims to stimulate research and teaching in the fields of medicine and law and the area where both disciplines connect: medical law. For a long time the foundation couldn't be found on the internet. It was up to me to create their on-line business card from scratch.

lancey responsive2

Already at the first conversation with the client it became clear the there was need for two different segments. On the one side the user should be able to find general information about the foundation, while on the other side the user should be able to find information about the founder. This is why I chose to let the user choose from the beginning, as is to be seen on the image above.

The website is fully responsive with very smooth navigation on both iPhone and Android devices.

Client Antoinette van Ouwerkerk on the project:

"Casper has helped us in a very professional manner. Engaging a conversation on the style of a website is tricky, but with just a few keywords Casper knew how to give our ideas a creative body. He also exceeded our expectation by continuously helping us on making the website practical and user friendly."

  • Infographic
  • WEJonker
  • 2016-09-14

Infographic WEJonker

My brother, Wieger Jonker, is a freelance graphic designer. It can't surprise you that me and him often collaborate. Where I can build a website, he can shape that very same website.

For his own acquisition, Wieger has designed an infographic. Then I modified it, so that there is interaction between the user and the inforgraphic. Instead of offering all the information at once, the user is informed step by step. This way it is easier to keep the user attention. 

Because the modified infographic is built in HTML5, the entire graphic can now also be indexed by search engines like Google and Yahoo!.

The infographic


Click here to view the interactive infographic in a seperate tab (best view).

The static infographic

Infographic WEJonker

  • Multimedia officer
  • SIRE | Group
  • 2013-09-01

SIRE | Group

Before I started out as a freelancer, I was employed at the SIRE Group. The SIRE Group is a European employment solutions provider. In the role as media officer I was responsible for website maintanance, online marketing and internal marketing. In my time at the SIRE Group I also created a big part of the corporate identity. Now the SIRE Group is a regular client of mine, for which I do different assignments.



The SIRE Group controls two websites. SIRE Life Sciences (recruitment in the life sciences industry) and (jobboard in the life sciences industry). For both I am partly responsible for the design and the maintanance.

Brochure 3


I am also responsible for all the print matter of SIRE Life Sciences. For example, I did the entire layout of the so called Black Book. A book that is used in the educational programm of SIRE Life Sciences. Below you will find an image of the brochure I designed.

Other activities


  • - On-line marketing in the form of newsletters (mail, html)
  • - Internal werkprocesses (digital forms)
  • - Branding (internal and external)
  • KIJK!
  • HvA
  • 2015-09-01

KIJK! een gezonde wijk

Afbeelding 7 locatie centraal

Commissioned by the research group Environment and Health I created a web application that allows users to indicate what they like or don't like about their neighborhood. I have done this project completely on my own, from design sketches to developing the web application.

Afbeelding 2 wijk naar kijk

All recorded observations are gathared in an overview. The users, municipalities, community organizations, police or other organizations involved can then use this information to improve the neighborhood.

Titel image

The indicators as shown in the current web application are placeholders. The final indicators are momentarily being assessed by the project organization. As soon as that's done, the web application can go live.

The application


  • Incident registration
  • UvA/HvA
  • 2015-08-18

Redesign incident registration

Incidents within the UvA and HvA are registrated through webforms. These forms are built by the professionals that process the incidents and therfor meet the content requirements.

By doing usability tests with the original forms I managed to find the biggest flaws in the design and the questions that are asked. After adjusting the design and questions I did another couple of usability tests with the endusers to verify that the adjustments have caused for improvements.

incidentenregistratie voor na

Clients Gijs Heukelom & Ronald Reiche on the project:

“The improvements Casper based on his research with the users made our forms for reporting safety incidents more user friendly. The questions are easier to understand: the jargon is replaced with the language of the users. Casper also adjusted the design so that it now looks more inviting. Because of this the forms will be filled in a lot faster. Very usefull imporvements that can also be applied to other forms.”

Examples of adjustments are:

  • - Adjusting the way questions were asked
  • - Automatically show or hide follow-up questions
  • - Relocating webelements
  • - Adjusting the visual design

The forms are not online yet, they will be in October 2015.

  • Samen slim met energie
  • Shifft
  • 2014-11-05

Samen slim met energie

Samen Slim met Energie is an innovation project from Enexis and energy coorperation DEH, in which they want to find out how energy consumption in Haaren can get smarter. Shifft offers the tools to get insight in the generation and use of energy. One of these tools is a smartphone application of which I was responsible for the interaction design.

deh app

In addition to the online energyplatform, the app offers the following functionalities.

  • - Realtime insicgt in the use of energy
  • - Insight in your personal use of energy and that of the community
  • - Energy usage advice to become smarter in your energy use
  • - Become friends with other users and become "samen slimmer!"

Client Stefan Versluis on the project:

“At Shifft Casper worked on the interaction design of an innovative smartphone-app to get real-time insight on energy usage in a social way. A challanging job which he executed on structual basis. With a keen eye and an interest in the end users opinion and without damaging the interest of the other stakeholders, he delivered an intuitive design which after development was succesfully implemented.”

This app can only be used by participants of the project.

  • LocalRoots
  • IJsfontein
  • 2013-02-04

Spreading tourists over Amsterdam

IJsfontein possesses a so called timeviewer. Now, it stands at the Westergasfabriek, but in the winter of 2013 it was gathering dust in a basement. IJsfontein has asked me and two colleagues to do something about that. Namely to find a way to better spread tourists over the city of Amsterdam.

To better spreak the tourists, they need to know about attractive alternative locations outside of the city center. From interviews with the tourists we know that these location are not known to the tourist. That's why we chose to show the tourists these location by using the timeviewer. Interest is aroused by giving the tourist the feeling he can look around live on the locations. Through observations in the city center we have decided where the timeviewer would stand, Dam square. Results from this research are summarized on the map below.

Toeristisch Centrum Amsterdam small

The timeviewer makes tourists curious and radiates that it should be used. This takes care of the first step: the tourists walks to the timeviewer. Then the tourists can take a look at the Dam square. In augmented reality the user will see different dots above the buildings circeling Dam square. The dots indicate attractive locations outside of the city center. With one click forwards on the timeviewer the user will see the location. By turning the timeviewer they can take a look at the location.

  • ONZO
  • Gemeente Amsterdam Zuidoost
  • 2013-01-18

Ontdek Ons Zuidoost 'ONZO'

This app was commissioned by district municipality Amsterdam Zuidoost and the Amsterdamse Federatie van Woningcorporaties. The assigment was to develop a multimedia product that would stimulate the students of Amsterdam to live in Amsterdam Zuidoost. My role in this project was that of Interaction Designer.

Check-ins (city guide)

The app offers the user a city guide with which he/she can discover the city district of Zuidoost by doing check-ins on several locations. These check-ins are devided into several categories: sports, nightlife, food, culture & education, fashion and electronics.

Social platform (community)

Users are also offered a social platform which can be shared with all the other users of ONZO. On the homescreen of the app there is a live feed, on which all events happening are displayed. This way the community can motivate each other to do more in district Zuidoost. Students that are active on ONZO can also get to know eachother.

Points (winning prices)

Check-ins, posting messages, making new friends and other activities within the app will give the user points. At the end of each month these points will give the user a reward. These rewards can vary from cinema discounts to free drinks at the local food store. First user to reach 10.000 points will get a room in district Zuidoost with the first months' rent for free.

  • Timesheets
  • Belastingdienst
  • 2016-09-10


As a freelancer, to make use of the different tax advantages, I need to comply to an hour quotum installed by the Dutch tax authorities. So it could happen that the tax authorities come to me for an overview of the hours I made working as a freelancer. This is one of the reasons I keep track of a timesheet. All the data of this timesheet I visualized in the graph below.

Feel free to change the dates and see what i was doing three, six or even nine months ago.

Last updated: 6-9-2016

Do you want to hire me? Please contact me. Together we will take a look at your project so I can create an action plan. Do you work in Amsterdam? Then I'll be happy to jump on bike to meet you.