How does stable Turbopack change builds in Next.js 16?

Turbopack becomes the default bundler in Next.js 16, providing 2-5x faster production builds, 10x faster Fast Refresh, and full compatibility with all Next.js features like App Router and Turbopack rules for custom optimization, eliminating Webpack entirely for most projects.

Example:

Code

// next.config.ts
const nextConfig = {
  experimental: {
    turbo: {
      fileSystemCache: true,  // Persists cache between builds
      rules: {
        '*.css': { loaders: ['css'] },  // Custom rules
      },
    },
  },
};

export default nextConfig;