Next.js 16.1 released with Turbopack file system caching, Next.js bundle analyzer and more

Next.js 16.1 has launched as the latest update to the popular open source React framework, with a focus on faster development workflows and greater stability. Developers will benefit from notable improvements to Turbopack and project tooling. Turbopack file system caching for the development server is now stable and enabled by default, which stores compiler artifacts on disk for much faster compile times, especially when restarting servers in large projects.

Building on these enhancements, the update introduces a new experimental Bundle Analyzer for Turbopack. This tool enables easier optimization of both server and client bundle sizes, helping to improve Core Web Vitals, lower lambda cold start times, and reveal unnecessary dependency bloat. The Bundle Analyzer is still in early development and will be refined further.

For debugging, developers can now enable the Node.js debugger in next dev by simply passing the --inspect flag. This change applies the inspector only to the relevant process, eliminating the need for global NODE_OPTIONS=--inspect workarounds. On the dependency management side, Turbopack now properly resolves and externalizes transitive dependencies when using serverExternalPackages, reducing setup friction and avoiding version conflicts.

Additional improvements include 20 MB smaller installs, a new next upgrade command, and other enhancements.