Interesting, doesn’t look efficient but that’s not really a big thing for most of those simple automation usages. Looks like a simple variable reactive language though (most languages have libraries to do the same too).
EDIT1: I could definitely write a little repl that looks like their repl but in rust around polars or so, lol.
EDIT2: Actually the nushell in rust can already do everything that they are showing there for data handling, plus can call out to other things with structured data as well, so already exists. ^.^