What I learned updating an existing iOS application to reflect changes that came from the latest iOS update: skeuomorphic components and iOS dark mode.
The one thing I recommend a developer do to level up their infrastructure skills. Also, a couple of stories illustrating how far infra and ops have come.
The Why of a story is more important than the What. To prioritize a story, people need to understand why they're supposed to build it in the first place.
Adding features and fixing bugs in an existing system doesn't generate much enthusiasm, but it still requires a great deal of creativity and ingenuity.