All great points! For the type of work I'm thinking of (mostly offline data processing) I use caches in a much more limited way than you suggest. A short-lived

All great points! For the type of work I'm thinking of (mostly offline data processing) I use caches in a much more limited way than you suggest. A short-lived local LRU cache on an expensive pure function over immutable data can significantly reduce our resource costs without adding significant complexity to the code. In some cases, DP would be more efficient but would require a mode of thinking and abstraction that's very different from most of our code.