Also, how does it "know" which parts are the important parts? Example, from the React repo, we have this: The key components of React's implementation incl

Also, how does it "know" which parts are the important parts? Example, from the React repo, we have this: The key components of React's implementation include: The reconciler, implemented in …/react-reconciler, which contains the ReactFiberReconciler class and algorithms for recursively diffing virtual DOM trees and scheduling rendering work. The beginWork and completeWork phases drive the reconciliation process. But the reconciler seems to be an experimental, not core, recent package, not a key one.