As mentioned earlier the nREPL protocol is language-agnostic and can be leveraged for many languages that have the ability to evaluate code at runtime.
Alternative Server Implementations
Those server implementations are developed and maintained by third-parties (as opposed to nREPL’s team), and their maturity might vary.
Certain nREPL clients may make Clojure-specific assumptions which will cause bugs when used with other servers, while other clients are designed with language-agnosticism in mind. Usually the nREPL servers would mention in their documentation which clients are known to work well with them.