Vertx uses Netty as the event loop handler for concurrent IO. Vertx adds a simplified asynchronous API on top of Netty (whose API can be pretty complicated), ma

Vertx uses Netty as the event loop handler for concurrent IO. Vertx adds a simplified asynchronous API on top of Netty (whose API can be pretty complicated), making backend services that need to handle large numbers of concurrent connections easy to implement. HTH