HelpBuilding and changing

"Looks good — harden it": proving your app works

Builds are fast and untested at first. Hardening writes the tests and an independent tester proves every promise in the plan.

While you are still shaping your app, changes are built quickly without tests so you can see them straight away.

When you are happy, hardening adds tests and a separate tester checks each promise the plan made ("a customer can pay an invoice"). Nothing goes to your test site or live until those promises are proven.