[$] Layers and abstractions

In software, we tend to build abstraction layers. But, at times, those
layers get in the way, so we squash them. In a talk at SCALE 17x in
Pasadena, CA, Kyle Anderson surveyed some of the layers that we have
built and squashed along the way. He also looked at some of the layers
that are being created today with an eye toward where, how, and why they might
get squashed moving forward.