[Update: This post got some well-deserved pushback. Thanks to Patrick Durusau, Lars Marius Garshol and Jack Park for the feedback – and sorry for the controversial headline. I’ve added “(as a standard)” and did some editing to make clear that people still use Topic Maps.]
I’m a fan of Topic Maps – the very well-thought-out Topic Maps Data Model standard with an XML serialization called XTM (XML Topic Maps) dating back to the year 2000. (See also the Topic Maps Reference Model, TMRM).
Even as a fan, I must admit that the Topic Maps standards are dead. They have never been widely adopted, and the key contributors have long moved on. Measured by the value you expect to get out of a successful standard – good visibility, adoption, interoperability, tooling, ongoing development – Topic Maps haven’t been the success we were hoping for.
I remain convinced that Topic Maps are one of the best ways to model information. As with other things, “out of fashion” doesn’t mean “wrong”. Since Topic Maps are a way of thinking about data structures, not a technology stack, they are rather timeless. Luckily, there’s still users and advocates of Topic Maps. Here are some of them:
Steve Pepper’s former company, Ontopia, still offers open source Topic Maps software.
The Wandora people who continue to work on a free Java desktop Topic Maps application.
Kamala is a commercial Topic Maps cloud app.
Jack Park makes Topic Map software in node.js and Java.
See also the Topic Maps Community on LinkedIn.
I’ll keep using Topic Maps (and building a TM engine), but for interoperability with the rest of the world, I’ll use RDF (as XML or JSON-LD) instead.
Please let me know if I’m wrong, or if anyone’s missing from this list of people who still actively support Topic Maps!
Update (2017-06-27): Brett Kromkamp develops TopicDB, “a Python topic map-based graph library”.
Update (2017-06-27): Michel Biezunski – Topic Maps Now: “The notions of topic mapping are still useful, even if they need to be adapted to new methods and systems. Furthermore, this flexibility in itself is a guarantee that they are still going to be relevant in the long term. […] The success was somewhat limited, and use of Topic Maps seems to be declining, which seems surprising given the fact that many web sites are organized around topics. Most of these tools are no longer maintained, and the activity in the ISO standard working group has decreased accordingly.”