I've had some bad days in my career — production outages, customer emergencies, escalations, you name it. But to be fair, I've never cost my employer $500 million because of poor UX or accidentally lost a $370 million piece of equipment because of an integer overflow.

While not all errors that we make are nearly this noticeable or catastrophic, we can learn from these notable mistakes how making human assumptions about the complex systems we create can lead to unintended consequences in the real world.

In this talk, we discuss both of these incidents - one highly technical and the other highly human and UX driven - to understand how a DevSecOps mentality is intended to overcome the biases we have for simplicity in our human model of complex systems. Lastly, we'll examine real-world solutions to automated testing and reasoning about how our modern, complex, distributed systems behave in the real world.