nextjs-upgrade
Next.js Upgrade
Resolve the requested target from the current Next.js release and upgrade guides, then compare it with the installed project. The bundled upgrade-path script is specifically tested for Next.js 15 to 16. Use its detection and measurement scripts for other targets, but derive migration steps from the matching official guide instead of presenting the v16 plan as current.
Why Scripts Handle Detection and Measurement
Scanning package.json, checking lock files, parsing build output — that's pure mechanics, not reasoning. These scripts handle it so you don't have to reconstruct the project state from scratch every time.
Quick Start
For a Next.js 15 to 16 migration, run the bundled scripts in this order. For any other target, run detection and measurement, then use the matching live upgrade guide and codemod documentation.