To use Cache::Static with XML::Comma documents and stores... 1) cache_static.macro must be installed in your defs directory (typically /usr/local/comma/defs or /usr/local/comma/defs/macros) (make install tries to do this automagically for you as of v 0.9901) 2) add cache_static to any def you want to be Cache::Static'able 3) start using it: Cache::Static::get_if_same($key, [ "file|/tmp/somefile", "_XML::Comma|Store|test3|main" ], "_XML::Comma|Doc|test2|main|000026" ] );