Clean Code, scaled up.

If you liked what clean code did mostly on a file by file basis and want the same kind of advice for designing applications, this is the book for you.

Like clean code, it is a very easy read without a lot of surprises. If you've designed applications before, this is mostly an experience of "oh, I'm not alone in encountering this problem" and "that's a succinct way of expressing it".

An example is his definition of an architectural boundary: "A line in the architecture diagram that is only crossed by dependencies in one direction". Stable abstractions principle et. al. provide good tools to think about software design and architecture. There are also some (albeit very few) tips on how to apply the principles in practice.

My main takeaway is some added structure to my existing opinions around application design and additional mental models for reasoning about architecture.

The book is however a little abstract in sections, and the last chapter is more autobiography than architecture book. Uncle Bob is very well aware of how well known and respected he is and that is obvious from the tone of the book, which would benefit from a little more humbleness.

I still recommend this book as I think it builds a good foundation of software architecture knowledge, with clear, well defined terms, and is an easy read.