Kotlin is great and we're using at in the backend at Datawire.io. Also we're hiring! Check us out if you're a backend JVM/Kotlin developer and are in the Boston, MA area!
Vert.x 3 currently. First class Kotlin support is dropping before the end of the year according to the Google Group for Vert.x but for right now the excellent Java/Kotlin interop hasn't prevented us from building.
I've built a couple Vert.x apps in Kotlin and honestly I can't even think what first class Kotlin support would add. Vert.x already feels like a perfect match to Kotlin.
Hard to say what's going on there. Vert.x itself is quite speedy. The DB access module they use (http://vertx.io/docs/vertx-mysql-postgresql-client/java/) is still in technical preview so there may be legitimate issue with the module or something wrong being done (I only glanced quickly and didn't see anything immediately obvious). Vert.x really isn't much more than a pleasant facade over Netty so it's hard to imagine what's actually wrong.
Personally, I don't really care about benchmarks. Getting stuff done is more important at this stage. Eventually this may become more important but I'm not going to worry about it until it becomes and issue for us specifically.
Hi! I am will join JetBrains in a week to work on new projects with kotlin and vert.x, but have only experience in Akka. Can you point any major issues that you have with vert.x + kotlin?
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