the core of didgmo is an executable, including a dozen functions. but the executable itself is not useful. the actual routines are programed into plugins, that are either invoked by the core executable or by another plugin.
from the point of view of the developer, this is the most simple approach for a massively extensible program.
the core executable and the plugins are by default written in C, because of compatibility and speed. but there is the possibility to develop plugins, which add scripting support. look at rank_lua as an example for partial scripting support.
the whole framework is by default console driven, but there is the possibility to develop plugins, which add a graphical user interface. look at the gtk plugin as an example.
the plugin system was inspired by the GIMP.