Interesting, I’ll check it out.

One intersection insight I had with stack languages is that they might lend themselves to an AST-like visual approach. The tree <-> postfix duality was an interesting aha for me that I’d long forgotten since that sophomore data structures class. :)

This looks very similar to RRDTool's query language. Is this a fork, or was it just inspired by RRDTool?

In that case, probably a fork, as Netflix used rrdtools extensively before Atlas.