Runtimes

Next.js has two server runtimes you can use in your application:

• The Node.js Runtime (default), which has access to all Node.js APIs and compatible packages from the ecosystem.
• The Edge Runtime which contains a more limited set of APIs.

Use Cases

• The Node.js Runtime is used for rendering your application.
• The Edge Runtime is used for Middleware (routing rules like redirects, rewrites, and setting headers).

Caveats

• The Edge Runtime does not support all Node.js APIs. Some packages may not work as expected. Learn more about the unsupported APIs in the Edge Runtime.
• The Edge Runtime does not support Incremental Static Regeneration (ISR).
• Both runtimes can support streaming depending on your deployment infrastructure.