How do you make sure your vibe-coded apps are actually secure?

I’ve been building a lot of apps using AI coding tools lately, and one thing I’m still not fully confident about is security.

When you’re vibe coding and shipping fast, how do you make sure you’re not accidentally introducing vulnerabilities, exposing API keys, or messing up authentication?

What tools, checks, or practices do you guys use before putting a vibe-coded app into production?