State Mechanics, Batching, and Lifecycle Transitions

The difference between junior and senior React developers often reveals itself when explaining why state behaves as an immutable snapshot per render frame. Candidates must clearly articulate how React batches state updates across event handlers and microtasks.

Explore React 18 automatic batching, learn why mutating state objects in place breaks re-rendering, master functional state updaters to overcome stale closures, and understand how functional components map legacy lifecycle methods to effect dependencies.