Done means released. Everything else is inventory.

Part 3. Part 1 was trunk-based development. Part 2 was continuous integration. Trunk-based development and CI enable Continuous Delivery.

What it is

Continuous Delivery means the head of master/main is always kept in a deployable state. The functionality is releasable to users, on demand, whenever the business decides.

Release is a business decision. The code is always ready to go. The question is whether you want to release it now.

On "CD won't work here." Every organisation thinks it is special. There are special rules and regulations that mean CD is not possible at their particular company. Despite evidence to the contrary from the research output from DORA data across thousands of organisations, including regulated industries, government, and finance. The rules blocking CD may or may not really exist, but they are rarely examined closely enough to find out.