MVC in React: Why We Use It, Why It Breaks, and What Production Apps Do Instead

You start a React project. Everything goes into one component. Three months later, nobody wants to touch that file — not even you. This article is about how that happens, why MVC was supposed to fix it, why it still breaks, and what actually works in production. Table of Contents Why Do We Even Need Architecture? What is MVC? MVC in React (With Real Code) The Fat MVC Problem How Fat MVC Happens (Step by Step) MVC vs MVVM vs Flux (Redux) Feature-Based Architecture: The Production Solution Full Production Example (Todo App) Common Mistakes to Avoid Which Architecture Should You Choose? Key Takeaways Why Do We Even Need Architecture? Let's start with a story. You're building a Todo app. Day 1, you write this: function App () { const [ todos , setTodos ] = useState ([]); useEffect (() => { fetch ( ' /api/todos ' ). then ( r => r . json ()). then ( setTodos ); }, []); const deleteTodo = ( id ) => { fetch ( `/api/todos/ ${ id } ` , { method : ' DELETE ' }); setTodos ( todos . filter ( t => t