Last year I attended the awesome AWS Community Summit where I gave this talk on one of the fundamental questions of software architecture: how do we define the boundaries of things?
A lot of people I talk to are confused about how serverless applications change the way we design stuff, but my answer is that the basics are exactly the same, and even more important.
It's taken me ages to remember to post it up here, but here it is, presented without further comment. The source for the slides is available under Creative Commons 0 licence on github with a somewhat cack-handed attempt at publishing it as a long-form article.