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:

Isidorus is licensed under L-LGPL (Lisp-LGPL).


For the time being, the only method to obtain Isidorus is to fetch it from our Subversion repository. If you are not familiar with subversion, then the probably best source of information is the Subversion book by Ben Collins-Sussman, Brian W. Fitzpatrick, and C. Michael Pilato.

The command for an initial anonymous checkout of the HEAD revision of Isidorus' trunk is:

svn checkout svn:// isidorus


Isidorus has quite a few dependencies, most of which can be easily installed via asdf. The file docs/install_isidorus.txt in the source tree gives detailed instructions where to get and how to install all the required libraries. Isidorus comes with an isidorus.asd file, too, so once all the prerequisites are in place, loading Isidorus is as simple as:

(asdf:operate 'asdf:load-op 'isidorus)

Last changed: 2008-12-12. Valid XHTML 1.0 Strict

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