Build and Deploy a Full-Stack AI App for Free (No Credit Card)

Step-by-step tutorial building Roomifi, an AI-powered architectural visualization SaaS that converts 2D floor plans into photorealistic 3D renders. Uses React, Vite, React Router v7, and Puter.js for serverless backend, AI models, and file hosting—all without credit cards or API keys. Covers authentication, drag-and-drop upload, progress tracking, routing, and AI code generation with JetBrains Juny and CodeRabbit for reviews. Implements user-pays model where infrastructure costs scale with users, not developers.