Signals in React (I): Without Breaking the Render Model

Why Does the Framework Affect How You Use Signals? The short answer is lifecycle . On social platforms, you’ll often see a group of React developers pretending lifecycle doesn’t exist while selling courses. That honestly worries me a bit—but once you go deep enough, you’ll realize this is mostly marketing rhetoric. After implementing our signal system step by step in previous articles, you should already have a solid intuition for what lifecycle actually means. In this article, we’ll clarify three key points: 1. Two-phase mental model React has Render and Commit. Render can run multiple times and be interrupted; only Commit mutates the DOM. 2. Timing alignment Our signals merge side effects in microtasks via a scheduler. React uses event batching and Concurrent rendering . 3. Forbidden zones and correct placement What must not happen during React’s render phase (e.g. createEffect , signal.set )—and where these belong instead. TL;DR In React, render must be pure (the Function Component