kdb+ is written in C, but q is (largely) written in k. One of the first things kdb+ does on startup is load the file `q.k`, which is a k file which defines the

kdb+ is written in C, but q is (largely) written in k. One of the first things kdb+ does on startup is load the file `q.k`, which is a k file which defines the q language. The interpreter then switches from interpreting k to interpreting q. Interestingly enough you can fairly easily program your own language (written in q/k) on top of that, and set the interpreter to evaluate that language by default. Kx offers a Python integration layer called EmbedPy which (among other things) exposes a Python evaluator as the "p" language in kdb+.