Do you use Laravel Shift or upgrade manually?

Both. Laravel Shift is an excellent automated tool that handles the mechanical parts of a Laravel upgrade (config file changes, namespace updates, deprecation fixes) and we use it as the starting point for most upgrades. Manual engineering work then handles the parts Shift cannot fully automate: third party package updates, custom code that uses deprecated APIs, business logic regressions, and integration testing. Shift reduces upgrade time significantly but does not replace senior engineering judgement on breaking changes.