How do you make sure developers in your team or in the company do not change the public API of the application when it is not planned? Yes you can write unit-tests, but they can also change/fix the unit-tests to have a green build.
In addition to normal unit tests, you can write tests whose job is a warning to a human being "you are about to do something dangerous, are you sure?" With a way to say "yes I meant to do that" when necessary.<p>Whereas unit tests test the product, these tests are oriented towards the development process.<p><a href="https://codewithoutrules.com/2016/03/01/process-reminders/" rel="nofollow">https://codewithoutrules.com/2016/03/01/process-reminders/</a> has an example.