The wonderful Metakit database is a very useful tool, and I use it for many of my projects, including Tigerbliss.
I would like to use mk (shortform for Metakit) in harmony with cgi.tcl, the rad dynamic web development library.
This page documents how to lock the mk db file, so that you don't get multiple processes writing to the same file at the same time -- which will inexorably corrupt your database.