Here are some talks I've given at usergroups and conferences:

Title Venue Year
Java 9 Modularity in Action JavaLand (Germany) & Luminis DevCon (The Netherlands) & GeeCON (Poland) & Devoxx UK (UK) & DevNation (San Francisco) 2016 slides, video (English), video (Dutch)
Java Modularity: Life After Java 9 JavaZone (Norway) & J-Fall (The Netherlands) 2016 slides, video
Provisioning the IoT Jfokus (Sweden) & IoT Techday (The Netherlands) & JavaOne (USA) & Luminis DevCon (The Netherlands) & DevNation (USA) 2015 slides, video (English), video (Dutch)
Event-sourced Architectures with Akka JavaOne (USA), J-Fall (Holland), Jfokus (Sweden) 2014, 2015 slides, slides+audio
TypeScript: Coding JavaScript without the Pain JavaOne (USA), DevNation (USA), GeeCON (Poland) 2014, 2015 slides, slides+audio, video
The Ultimate Dependency Manager Shootout QCon New York (USA) 2014 slides
Modular JavaScript JavaOne (USA) & J-Fall (Holland) & JavaLand (Germany) & GeeCON (Poland) & QCon New York (USA) 2013, 2014 slides, video (English), video (Dutch)
Data Science with R for Java developers
JavaOne (USA) & J-Fall (Holland) 2013 slides, slides+audio
Modularity in the cloud: a case study JEEConf (Ukraine) 2013 slides, video
Cross-Build Injection attacks: how safe is your Java build? JavaOne (USA) & J-Fall (Holland) 2012 slides, slides+audio, video (Dutch)
Hibernate Performance Tuning JEEConf (Ukraine) 2012 slides, video
Elevate your webapps with Scala and Lift JEEConf (Ukraine) 2012 slides, video
Fork/Join and Akka BeJUG (Belgium) 2012 Part 1: slides, slides+audio
Part 2: slides, slides+audio
Fork/Join for Fun and Profit! J-Fall (Holland) 2011 slides, video (Dutch)
Elevate your webapps with Scala and Lift J-Fall (Holland) 2010 slides
JDK7: Improved support for dynamic languages J-Fall (Holland) 2009 slides
Scala: functional programming for the imperative mind Info Support (internal) 2009 slides