Good job, you convinced me to give docker a real try this time ;-)
Very nice talk.
I just think that a little time was lost while your where repeating 3 times the same thing. When you explained the process of making the behavior tests, having them fail, then making the unit test making them fail, then having the unit tests pass and finally the behavior test pass.
Maybe you could use one of those repetition to actually show the unit tests too.
To really see the relation between the behat and unit tests.
Great talk overall.
Great job for a first time speaker and on topic while maintaining a good tempo. Even with live demo's that actually worked (which is - to say the least - not always the case).
Nice and clear overview. Thanks!