It's interesting to compare that version from 2017 with the current version from 2025: https://github.com/KxSystems/javakdb/blob/9a94dc5af9288fe845... — the current one is over ten times as long in terms of number of lines, and has copious comments, but still has the short names and dense code.

People here might not notice - your link is the official client interface for talking to KDB+ processes from Java.

There's a decent chance your broker (or their dealers) are using stuff built on this.