This idea + Domain modeling go together like peanut butter and chocolate. The idea that an invalid state in your Domain is unrepresentable takes so much work of

This idea + Domain modeling go together like peanut butter and chocolate. The idea that an invalid state in your Domain is unrepresentable takes so much work off the database and API, and makes programs so easy to test-- since an invalid Domain representation simply will not parse, and can never make it to your API or DB, taking so much logic out of the parts of a software stack that are hardest to test.