Yet another fascinating technology from the sixties still in use today; at least the database part of it came back into fashion with NoSql; the language, on the other hand, does not exactly promote readability.

If you consider funneling a non-negligible fraction of US medical costs into paying for Intersystems Cache licenses fascinating, then yes!

Those fuckers are well aware of their captive markets and extract rent like no other. The licensing costs on such an outdated piece of technology are obscene.

> extract rent like no other .. The licensing costs on such an outdated piece of technology are obscene.

They're in "good" company. Do you think its less obscene to pay the horrendous license costs to companies like Oracle or SAP?

Anyway, I'm talking about the technology, which btw. has established open source alternatives. I once had an argument with the main person in charge of hospital IT, and he made it clear that he didn't want to risk his good sleep by using technology from non-mainstream suppliers, no matter what the cost. As long as we allow such people to value their personal sleep quality over the cost to the health care system, we need not complain about the consequences.

Can you point out a few of these open source alternatives? Asking for a friend...

The most obvious alternative is https://sourceforge.net/projects/fis-gtm/, but there are a few others, depending on the size of the application at hand. https://yottadb.com/ is another big one which started on GT.M a few years ago, or http://minimdb.com/. See also https://www.mumps.dev/implementations.cfm.

If you don't depend on the MUMPS/ANSI-M language or don't have to be backwards compatible, a lot more alternatives with similar features are available, e.g. https://github.com/facebook/rocksdb run behind e.g. Node.js.