Everything is Broken and I Don't Know Why

We all have someone on our team who writes code with bugs in it. Not us, of course, but someone else. This code somehow gets into production and this code just maybe sometimes crashes. How can we detect these issues and extract useful information at runtime so we can fix these bugs? What kind of stuff should we even be looking for? Sentry developer Matt Robenolt discusses these questions in this talk from JSConf. He's given versions of this presentation multiple times since.