There is one plausible solution to this inequality: the Unix philosophy. Small parts, loosely coupled. Individual parts can't be significantly changed or remove

There is one plausible solution to this inequality: the Unix philosophy. Small parts, loosely coupled. Individual parts can't be significantly changed or removed, but they can be deprecated and better alternatives added. Because the parts themselves are small, they're less likely to have errors and replacing them is cheap. Rich Hickey also has a talk on this. And there's also an overlap with CRDTs (basically you have a distributed system unless you can refactor everything atomically).