If you are running Clojure on Java11 you can use the newly added HttpClient which has full support for HTTP/2. The API is a bit java-ish but works well enough from Clojure.
(ns foo.test
(:import [java.net.http HttpClient HttpRequest HttpClient$Version HttpResponse$BodyHandlers]
[java.net URI]))
(let [req
(-> (HttpRequest/newBuilder)
(.uri (URI/create "https://www.google.com"))
(.GET)
(.build))
client
(-> (HttpClient/newBuilder)
(.version HttpClient$Version/HTTP_2)
(.build))
res
(.send client req (HttpResponse$BodyHandlers/ofString))]
(println (.body res)))
The entire java.net.http
package is pretty powerful and supports everything you’ll ever need to do HTTP requests. Assuming of course you are running Java11 and Clojure.