Does Janet have something like Clojure's threading (->, ->>)?
On a related note: it would be an interesting read if someone tried tracing the threading macros to some origin point(s) in the past. There seem to be two main variations, Lisp's ->/->> and |> in many functional languages (Elixir, OCaml, Raku). The construct seems to have gotten popularized by Clojure and F#, but I don't think it was invented in either (maybe rediscovered).
It had to start at some point, somewhere, but I wasn't able to locate that point.