Looking for TFM on OS X module building

[Tim Bray]

I'm sketching in a module for 2.2.4 and having trouble with compiling  
it on OS X.  Neither google nor a survey of this group's archive turn  
up any ideas.  Suppose I have mod_foo.c; I assume the goal is to  
produce a mod_foo.so or mod_foo.dylib in $INSTALL/modules/

Is this written up anywhere, or alternatively does anyone have any  
experience to share?

 -Tim (who previously wrote two big Apache 1.* modules and is  
feeling a little lost in 2.2-land)