Anastasia is a SGML/XML publication tool which allows the processing and searching of large documents using tcl scripting. See https://github.com/peterrobinson/Anastasia2 for updated code, etc, for running in Apache 2 environments.
e4Graph is a C++ library and a Tcl binding providing persistent, reliable, cross-platform storage for graph like structures. Please visit http://e4graph.sourceforge.net for more info.