How to Use New Next.js 15 Parallel Routes for Building Dashboard Layouts With React 19 Next.js 15 introduced Parallel Routes, a powerful feature that lets you render multiple page slots in the same layout simultaneously, with independent navigation and state. When paired with React 19’s latest concurrent features and Server Components optimizations, building modular, high-performance dashboard layouts becomes faster and more intuitive than ever. What Are Next.js 15 Parallel Routes? Parallel Routes allow you to define multiple "slots" in a layout that map to different URL segments, each rendering their own page component. Unlike traditional nested routes, parallel routes load independently: navigating to a URL that updates one slot doesn’t trigger a full reload of other slots, preserving state and improving performance. To define parallel routes, you use the @folder naming convention in your Next.js app directory.…