Werner Altewischer, Developer in Arnhem, Netherlands

Werner Altewischer

Software Developer

Arnhem, Netherlands
Toptal Member Since
June 26, 2017

With an M.Sc. in physics and practical experience in robot soccer, Werner started his IT career as a Java back-end developer in 2002. He's contributed to startups in Silicon Valley and elsewhere, and has been freelancing for the better part of a decade—mainly on iOS apps but also maintaining his chops in Java on the side. He has experience in Scrum and Agile environments and on teams of all sizes.

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Swift, Objective-C
Behind Media
iOS, Objective-C, JPA, Hibernate, Spring, Java


Arnhem, Netherlands



Preferred Environment

Jira, Xcode, AppCode, IntelliJ, Git, MacOS

The most amazing...

...project I've worked on was within my startup company Layerstream, building a real-time scalable video codec extension based on FFmpeg.

Work Experience

2013 - 2017

Lead iOS Developer/Architect

  • Implemented a universal iPad/iPhone application for the biggest supermarket company in the Netherlands for browsing products and special offers, creating delivery/pickup orders, guidance within the supermarket, and much more.
  • Contributed to the mobile services back-end implemented in Java using Spring.
  • Contributed to the Allerhande Koken iPad app which won a design award in The Netherlands, an app for cooking recipes.
  • Extended my open source BMCommons framework for creating iOS applications (available on GitHub). Used by all Ahold apps.
  • Worked in a Scrum team as lead developer.
Technologies: Swift, Objective-C
2011 - 2016


Behind Media
  • Co-founded the startup Behind Media for the creation of an app platform called BehindTheFrontDoor, a leaderboard for talent.
  • Designed and developed BehindTheFrontDoor's server-side functions and iPhone app.
  • Developed several open source modules, including WEPopover and BMCommons, both of which are available on GitHub/Cocoapods.
  • Developed an iPhone app for JeromeFitness based on the same back-end and open source libraries.
  • Worked using Scrum methodology.
Technologies: iOS, Objective-C, JPA, Hibernate, Spring, Java
2012 - 2013

iOS Developer/Architect

  • Implemented a corporate iPad application for a root maintenance company to log and plan maintenance work.
  • Worked in a small Scrum team of two developers, a designer, and a project leader.
  • Implemented an asynchronous synchronization mechanism to avoid the app needing internet at every moment.
  • Contributed to the Python based REST back-end for the application.
Technologies: Objective-C
2012 - 2012

Technical Consultant

  • Advised on implementation for a Java text search engine based on Lucene.
Technologies: Apache Lucene, Java
2010 - 2012

iOS Developer/Architect

  • Implemented the KLM customer facing app for searching and booking flight tickets, electronic boarding, etc.
  • Developed several internal iPad applications for both the cabin crew and the flight crew and an internal Wiki for all personnel.
  • Worked in a team using Scrum methodology.
Technologies: Objective-C, iOS
2011 - 2011

iOS Developer

Coz Marketing
  • Implemented a contact management application for a company named VCP containing media and in-app purchasing functionality.
Technologies: Objective-C, iOS
2010 - 2011

iOS Developer/Architect

  • Implemented the Greetz iPhone app, an application to design greeting cards on the mobile phone, containing optional sound, stickers, photos, and custom drawings/writings with effects and transforms.
  • Implemented a payment system connecting to different payment providers, such as Ideal, different credit cards, and PayPal.
  • Handled technical implementation of all parts of the app.
  • Won the award Best Mobile Webshop with the Greetz app.
Technologies: Objective-C, iOS
2009 - 2010

iOS Developer

Global Motion
  • Implemented the 3.x an 4.x versions of the iPhone app for EveryTrail, a GPS tracking and trip sharing application, integrating with the EveryTrail website.
  • Contributed to the acquisition of the company Global Motion by TripAdvisor.
  • Worked mostly remotely in a small team of one other developer, a designer, and a project leader using video communication methods.
Technologies: Objective-C, iOS
2008 - 2009

iOS Developer, Platform Architect

Global Motion
  • Set up the development environment with issue tracking, source control, automatic deployment, and a documentation system.
  • Advised on architecture of the platform, technical choices, and development strategies.
  • Implemented the first version of the EveryTrail iPhone application for recording and sharing GPS track data using the EveryTrail web platform.
  • Implemented several side applications, such as Wherester, BikeComputer, SkiComputer, and GeoTagging. All applications relied on GPS tracking and sharing with EveryTrail.
Technologies: Objective-C, iOS
2008 - 2009

Java Back-end Lead Developer/Architect

  • Professionalized the working environment by setting up source control, issue tracking, and documentation systems, and set up automatic builds and deployments.
  • Architected and implemented the core product of Impressie, called Impressie Publisher: a content management system based on Spring/MySQL and Lucene for text search.
  • Created documentation and led junior developers.
Technologies: Apache Lucene, MySQL, Spring
2007 - 2008

Co-founder and Video Expert

  • Co-founded Layerstream, a startup company working on technology for optimized real-time video streaming over unreliable networks (such as the internet).
  • Worked on extensions to existing video codecs for scalable video coding (SVC), mostly based on FFmpeg.
  • Contributed to the Windows based demo video player based on C#.
  • Did some business development by talking to potential strategic partners, attending VC meetings and other events in the Silicon Valley region.
  • Contributed to the Java based router software components.
Technologies: H264, MPEG, Video Codecs, C, C#, Java
2004 - 2007

Java Developer

  • Implemented the Java-based UserXS application, an authentication and authorization application exposing a SOAP API over HTTPS.
  • Contributed to other parts of the MarketXS finance engine platform, an architecture to distribute real-time financial market data across the internet. MarketXS was acquired by Markit in 2006, after being the fastest growing technology company in the Benelux within the period 2000-2005.
Technologies: SOAP, Java Data Objects (JDO), Jakarta EE, Java
2002 - 2004

Java Back-end Developer

  • Contributed to the development of the Nuon service broker, an internal J2EE based SOAP architecture to connect different back-end and front-end systems within Nuon.
  • Contributed to the migration of Windows NT servers to Unix servers.
  • Worked on the implementation of a new Siebel/SAP-based CRM application for the Nuon energy company.
Technologies: SOAP, WebLogic, Jakarta EE, Java
1998 - 2002

Software Developer

  • Contributed to the automation of different types of text conversions for creating searchable text archives.
  • Performed hardware and software installations and configurations.
  • Developed in different programming languages and tools such as Java, Visual Basic (for applications), C++, Javascript, HTML, and XML.
Technologies: C++, Visual Basic for Applications (VBA)


BMCommons Framework for iOS Applications

An open source framework solving/simplifying many of the common problems in creating an iOS application.

It supplies many utility functions, a REST engine, UI extensions, base classes for view controllers, and much more.

WEPopover Component for iOS

An iPhone UI component mimicking the iPad UIPopoverController for pop-over views in a phone application.

Appie Universal iOS App for Shopping in the Biggest Supermarket in NL

An iOS app, built for both iPad and iPhone and incorporating a web shop to shop at the biggest supermarket in the Netherlands and to help during your offline shopping journey with many utilities, such as a bar code scanner, a wine selection utility, recipe search/browse, bargain search/browse, shopping list optimization for a given walking route, etc.



Java, Swift, Objective-C, C, Visual Basic for Applications (VBA), Bash Script, SQL, C#, C++, Ruby


iOS SDK, OAuth 2, Spring Security, Spring MVC, Spring, Hibernate, JPA


Spring REST, Hibernate Search, Apache Lucene, Java Data Objects (JDO)


IntelliJ IDEA, AppCode, Xcode, Calabash, Git, IntelliJ, Jira, RubyMine


REST, Agile, Scrum, Concurrent Programming


MacOS, iOS, Jakarta EE, Linux, Amazon Web Services (AWS)


Spring Data REST, Spring Data JPA, HSQL, MySQL


Data Structures, Jakarta EE Design Patterns, Linux Server Administration, SOAP, Algorithms, WebLogic, MPEG, H264, Video Compression, Video Codecs


2007 - 2007

Sun Certified Web Component Developer in Java Web Programming

Prometric - Amsterdam

2007 - 2007

Sun Certified Programmer in Java 5

Prometric - Amsterdam

2003 - 2003

Sun Certified Java Programmer in Java 1.4

Azlan - Amsterdam

2002 - 2002

Certificate WLS-D21-70 in Developing Enterprise Applications with BEA WebLogic

BEA - Amstelveen

1995 - 2002

Master's Degree in Applied Physics

University of Technology Delft - Delft