Marko is a long term WordPress contributor from the Netherlands. He uses wordPress since 2006 and started contributing back to it in 2009.
After years of freelancing he now works for his own agency CodeKitchen B.V. Part of his job is improving WordPress by contributing back to the community. He is also a lead developer of GlotPress since early 2013 which is a open source tool for collabrative translating.
He can be found on Twitter @MarkoHeijnen or one of his blogs at markoheijnen.com and wpunknown.com.