What’s new in Next.js 12

Next.js 12 introduces several innovative features aimed at enhancing performance and developer experience within the React ecosystem. The update replaces the Babel compiler with the Rust-based SWC, significantly speeding up compilation and build times, thus improving both local development and production processes. Next.js 12 also integrates middleware capabilities, allowing developers to execute code before requests are completed, enabling dynamic modifications and improving code efficiency by sharing logic across pages. Additionally, it supports experimental features from React 18, such as server-side Suspense and React Server Components, which enhance server-side rendering and data fetching. The framework now defaults to ES module support, and introduces URL imports, offering more flexibility in handling dependencies. Incremental Static Regeneration (ISR) has been improved to automatically server-render pages for web crawlers, preventing the indexing of loading states, while AVIF image support ensures smaller image sizes for optimized performance. Finally, the update includes enhancements like output file tracing, leveraging Vercel's tools to improve the management of dependencies and assets. These updates position Next.js 12 as a transformative release, poised to redefine how React applications are developed.