Speaker: Ana Balica Mocking is a very powerful testing concept that has some dangerous pitfalls. There are obvious use cases where mocks are an absolute requirement to be able to test a part of the app. Nevertheless sometimes apparently useful mocks can yield erroneous test results. This talk goes into deeper detail on the trade-off of using mocks in testing. Slides can be found at: https://speakerdeck.com/pycon2016 and https://github.com/PyCon/2016-slides