(Because "Cosmos" is the opposite of Chaos, you see)

The Book

There are lots of ways you can read the book. Some of them even involve us, the authors, receiving a small amount of money!

• Read it online on O'Reilly Learning (aka Safari) learning.oreilly.com
• Buy print books on Amazon.com or Amazon.co.uk.
• Buy a DRM-free ebook at ebooks.com
• Or read it for free on this site (license: CC-By-NC-ND).

Blog

Recent posts

• 2020-10-27 Making Enums (as always, arguably) more Pythonic
• 2020-08-13 So Many Layers! A Note of Caution.
• 2020-05-12 Book review: Designing Data-Intensive Applications, by Martin Kleppmann
• 2020-01-25 Writing tests for external API calls

Guest Posts By David

• 2019-08-03 Three Techniques for Inverting Control, in Python
• 2019-04-15 What is Inversion of Control and Why Does it Matter?

Classic 2017 Episodes on Ports & Adapters, by Bob

• 2017-09-19 Why use domain events?
• 2017-09-13 Commands, Handlers, Queries and Views
• 2017-09-08 Repository and Unit of Work Pattern
• 2017-09-07 Introducing Command Handler