The language lock-in issue seems to be mostly an issue with Lambda at the moment, and I suspect it will resolve itself over time. As it, even on Lambda you have

The language lock-in issue seems to be mostly an issue with Lambda at the moment, and I suspect it will resolve itself over time. As it, even on Lambda you have the choice of JS, Python, and Java, which is a lot of flexibility. I expect we will see "official" Go, Ruby, JVM languages like Clojure and Scala, etc. If you can't use some obscure hipster language, that might be a problem. But my biggest gripe at the moment is lack of Ruby, and I'm sure Amazon will fix that.