I'm spending a fair amount of time contributing to open source projects. Mainly around the area of Qt/KDE and C++ but not limited to them.
2012 - now | Contributing to the open source IDE KDevelop, focussing on the Clang integration, cross-platform support and general QA (http://kdevelop.org/)
2006 - now | Supporting member of the KDE community (http://kde.org), helping out in various areas of the project, not just limited to contributing code.
2017 | Google Summer of Code (GSoC) as mentor. Contributing to the OpenSource IDE KDevelop, focussing on the Clang integration, cross-platform support and general QA
2015-2017 | Via KDAB: New IPC module framework QtRemoteObjects for the automotive sector. Worked on the module en bloc. Helped upstreaming it to Qt proper.
2015-2016 | Via KDAB: Extra views written in Qt/QML for self-service terminals. Worked on server backend written in Qt processing XML data from external service and GUI bits.
2015-2016 | Preparing an initial version of KDevelop to other platforms such as OS X and Windows. KDevelop was a purely Linux-centric IDE before.
2015 | Released KDStateMachineEditor, a framework for creating & viewing state charts. Used inside KDAB's GammaRay (a introspection tool for Qt applications) for real-time tracking of state machines embedded in Qt applications.
2014 | Participated in GSoC 2014 (https://www.google-melange.com/gsoc/homepage/google/gsoc2014) for streamlining the C/C++ support in KDevelop by integrating libclang (from LLVM) as parser backend. See blog series.
2014 | Implemented a full CBOR (RFC 7049 Concise Binary Object Representation) encoder/decoder in C as part of the RIOT operating system for heavily constrained nodes as part of a university research project. Implementation is covered by extensive unit tests. Also listed on the spec page: http://cbor.io/impls.html
2013 | Joined the KDE eV. (http://ev.kde.org/)
2010 | Via KDAB: Participated in the Valgrind plugin development for Qt Creator driven by KDAB. Main focus: Callgrind visualization: http://doc.qt.digia.com/qtcreator-2.3/creator-cache-profiler.html)
2006 - 2009 | Amarok (https://amarok.kde.org/) bug triaging and minor feature development (KNotification backend)