🔗 150,000 lines of Vibe coded Elixir: the good, the bad, and the ugly

TL;DR:

• Good: AI is great at Elixir. It gets better as your codebase grows.
• Bad: It defaults to defensive, imperative code. You need to be strict about what good Elixir looks like.
• Ugly: It can’t debug concurrent test failures. It doesn’t understand that each test runs in an isolated transaction, or that processes have independent lifecycles. It spirals until you step in.
• Bottom Line: Even with the drawbacks, the productivity gains are off the charts. I expect it will only get better.

BoothIQ is a universal badge scanner for trade shows. AI writes 100% of our code. We have 150,000 lines of vibe coded Elixir running in production. Here’s what worked and what didn’t.