Kimwitu (pronounced kee'mweetoo) is a system that supports the construction of programs that use trees or terms as their main data structure. it is a meta-tool in the development process of tools.

it can easily be interfaced with yacc and lex - the idea is that yacc and lex are used to do the parsing, and kimwitu routines are used to built and manipulate the parse tree.

there is also kimwitu++ (also packaged for debian) which interfaces with c++ instead of c; its documentation is still a little shaky, so this document might be useful for it.