I've been using IkiWiki for my personal site since 2008, as well as a number of private instances.
contributions
I've worked on a few different issues and bugs over the years (they are probably linked in "Backlinks", below) but these days my main effort is the Opinionated Ikiwiki container.
historic
I gave a talk at the UK UNIX User's Group annual Linux conference in 2008 about organising system administrator documentation. Roughly a third of this talk was discussing IkiWiki in some technical detail and suggesting it as a good piece of software for this task.