next-upgrade

The safest way to upgrade Next.js is applying official codemods to migrate APIs and configuration, handling major version jumps incrementally to preserve project behavior.

Next.js codemods work by automatically applying transformations to your codebase, updating APIs and configuration to match the target version. They handle incremental version steps, ensuring your project's behavior is preserved while updating dependencies like React and React DOM.

Yes, you can upgrade a Next.js project whether it uses the app directory or the pages router. The upgrade process applies official codemods and dependency updates to both routing architectures, preserving existing project behavior while moving to the latest version.

The best way to handle incremental Next.js version jumps is to move through major versions in safe, sequential steps, applying official codemods and updating dependencies at each stage before validating the build to ensure stability.

Yes, you need access to your project's package.json and next.config.js files to automate a Next.js upgrade. These files are required to update dependencies and configuration while applying official codemods to migrate the codebase.

Upgrading Next.js and React dependencies causes breaking changes when major version updates introduce API modifications or configuration requirements. Applying official codemods during the upgrade process automatically migrates these APIs and updates configuration to prevent build failures.