This is a very thick talk, one Rich's best ever IMHO.
The first point is how we talk about 'change' in software, to center around what things 'provide' and 'require'.
Breaking changes are changes that cause code to require more or provide less. Never do that, never need to do that. Good changes are in the realm of providing more or requiring less.
There is a detailed discussion about the different 'levels' - from functions, to packages, artifacts, and runtimes, which he views as multiple instances of the same problem. Even though we now have spec, theres a lot of work to leverage it across all those different layers to make specific statements about what is provided and required.
The first point is how we talk about 'change' in software, to center around what things 'provide' and 'require'.
Breaking changes are changes that cause code to require more or provide less. Never do that, never need to do that. Good changes are in the realm of providing more or requiring less.
There is a detailed discussion about the different 'levels' - from functions, to packages, artifacts, and runtimes, which he views as multiple instances of the same problem. Even though we now have spec, theres a lot of work to leverage it across all those different layers to make specific statements about what is provided and required.