Hi, I'm Wikiklaas (at least, that's my codename on Wikimedia). I was born in the Netherlands. When I first discovered Wikipedia and felt the urge to contribute to this project, I registered on the English language version. That was in december 2005. Little later, I also created an account on the Dutch Wikipedia. That's where I'm most active now.
I do however also contribute to commons, where I mainly correct filenames of incorrectly identified organisms, and occasionally provide correct license tags. And after the rollout of Wikidata, I have been busy merging duplicate items, shifting language links in items that hold unequal subjects, and providing English labels and descriptions to items there.
If you want to contact me and wish me to notice soon, best visit my Dutch talk page. It's okay if you leave a message in English, German or French there. I will understand and do my best to answer in the language you chose. Note that I will answer your question or remark where you left it.