Recompute is a lightweight selector library for Redux (and similar state‑management systems) that lets you define **observers**—simple functions that read pieces of state—and **selectors**—memoized, composable functions that compute derived data only when their observed inputs change. It’s aimed at React/Redux developers who need performant, reusable selectors that can be shared across component instances, accept any number of arguments, and have an unbounded cache.