Dave is a pillar of the IndieWeb community. Most notably, he's helped organize several of our largest in-person social events, including our yearly IndieWeb Summit conferences, and he's always willing to help run A/V or monitor the chat for attendee questions.
Perhaps even more important, however, is all the work Dave does to welcome new and curious members to our community. He sets a fine example for newcomers by using his website to showcase everything from photos, to vacation records (with maps automatically generated from his itineraries), to journal entries from bygone years. He also puts his archiving and librarianship training to use on behalf of IW members trying to orient themselves among the blog posts, wiki pages, chat logs, and technical specifications which this community has created over the last decade. I've lost count of the number of times when, after someone referred to a IndieWeb topic, Dave was able to recall precisely when it debuted, or summarize the history of its development.
Finally, Dave is the maintainer and programmer of Wordpress plugins which offer instant IndieWebification of any site built on that platform. As I understand it, hundreds of website owners who would not otherwise be part of the IndieWeb (except by the broadest definition which includes all personal websites) owe their ability to participate in our network directly to Dave.
Yom hu'ledet sameach, Dave, and may you have many more happy years!