From the website:
Isidorus is an Open Source Topic Map engine actively developed using sbcl and elephant. Isidorus supports import and export of XTM 1.0 and 2.0, full versioning, merge semantics, an Atom-based RESTful API and Topic Map querying — with more to come.
Current areas of development include:
- Enforcements of constraints (TMCL)
- Json-import / export and a AJAX front end for data curation
- Enhanced querying
A Virtual Box image of a pre-installed isidorus-environment on an Ubuntu-Linux system is available at: http://festus.textgrid.it.fh-worms.de/TMRA2009/isidorus-vbox-image.tar.gz.