I have been developing plugins and extensions for elgg since 2009 February. Currently I am acting in some plugins development, fixing/upgrading some elgg plugins that are not being continued and modifying or extending the Elgg Framework itself.
I'am R&D engineer in a standardisation organisation. We use Elgg as the internal Company directory. As i really love the nice modeling approach of this tool, i made several plugin both for my company and the community.