Backend development with hot loading

I am new to clojure and lein, We meet some problem when develop backend with hot loading. Since we found that "lein ring server" is not available any more, and accroding with this issue, we turn to use "lein repl". But unfortunately, still see the problem of "metabase.async.streaming_response.StreamingResponse".
So, "lein run" is the only options, or there're any good way to achive hot loading. If anyone know that, I will very appreciate.

Our version is 0.38
and the error log is

 "No implementation of method: :render of protocol: #'compojure.response/Renderable found for class: metabase.async.streaming_response.StreamingResponse",
 "No implementation of method: :render of protocol: #'compojure.response/Renderable found for class: metabase.async.streaming_response.StreamingResponse"}

There's no workaround. But Leining has been removed in upcoming 0.41 and there has been a lot of other changes and fixes to the build process.

Get it, is there any way to make lein run startup faster? It took a few minutes to do that after I edit some file. Or go with unit test first is the best practices?

@KEN-LJQ If you upgrade to 0.41 or master, then it's much faster.

Thanks, it helps a lot.