And you can pick any language you'd like as it supports arbitrary containers now too: https://news.ycombinator.com/item?id=25267182
This is really, really exciting!
We use very little serverless at the moment, because the three clouds we need to deploy to have infuriating differences between their execution and deployment environments. Eg. How they manage dependancies, the runtimes, how you describe and deploy each function.
Compared at least to K8 where the containers you build run just fine wherever you put them.
Docker containers can be up to 10gb, traditional lambdas are still limited to 250mb.