We just build a JAR and deploy it using Terraform, our Lambdas are used only for infrastructure stuff so they don't change that often

have you looked at #nbb ? that can run on Lambda's. I haven't tried it myself though.

HL is excellent. we use it for many lambdas in prod

HL is quite minimal and ships with the great performance. It's faster than running Clojure on official Java runtime consume less memory.

The current pain points are the HL tasks that are planned to get rewritten in few weeks / months depending on my mood :D