GT.M High end TP database engine (Sourceforge)
Description from the commercial version:
The GT.M data model is a hierarchical associative memory (i.e., multi-dimensional array) that imposes no restrictions on the data types of the indexes and the content – the application logic can impose any schema, dictionary or data organization suited to its problem domain.* GT.M’s compiler for the standard M (also known as MUMPS) scripting language implements full support for ACID (Atomic, Consistent, Isolated, Durable) transactions, using optimistic concurrency control and software transactional memory (STM) that resolves the common mismatch between databases and programming languages. Its unique ability to create and deploy logical multi-site configurations of applications provides unrivaled continuity of business in the face of not just unplanned events, but also planned events, including planned events that include changes to application logic and schema.
There are clients for node-js:
http://github.com/robtweed/node-mdbm
http://github.com/robtweed/node-mwire
Local topic map software is interesting and useful but for scaling to the enterprise level, something different is going to be required.
Reports of implementing the TMDM or other topic map legends with a GT.M based system are welcome.