We all try to write the best code we can, but sometimes things slip through the cracks. With a look at the data from scans of thousands of projects, we can tell what the most common issues are in the codebases of all TypeScript developers. In this talk we’ll take a look at those top issues that plague TypeScript projects around the world, we'll see why they are issues, and finally how to spot and avoid those common errors, issues or anti patterns. By the end of the talk you’ll feel more confident in your codebase and maybe have a few things to fix.