What happens when a handler function for a specific event fails

[creativefctr]

My actions before raising this issue

• [*] Followed the troubleshooting guide
• [*] Read/searched the docs
• [*] Searched past issues

I read all the docs but this was never mentioned. How are execution failures handled? What happens after the function that (for example) reacts to a Kafka message fails due to a runtime error? Will the message be lost? Do we have retries? What's the best practice for handling such situations?