> I'd say that Racket has the best one I've used. I love that you can specify a '_' for the hole which the result from the previous operation will fill.

Clojure also has a placeholder variant, the as-> form. Quoting the example the Clojure doc page (https://clojure.org/guides/threading_macros):

  (as-> [:foo :bar] v
     (map name v)
     (first v)
     (.substring v 1))
  
  ;; => "oo"