Rekey - EntityId Migrator for Unity 6.5+
A Unity editor tool from Core Systems Asset Factory. Made with Unity. Paid.
Rekey - EntityId Migrator for Unity 6.5+ is a Unity editor tool for Unity, paid.
Its title or description names Unity 6.
Unity 6.5 says error CS0619: 'Object.GetInstanceID()' is obsolete: 'Use GetEntityId instead.' and your project stops compiling. Rekey gets it compiling again. Unity 6.5 turned the instance ID APIs into compile errors and made EntityId 64-bit, and Unity's own migration guide says its script updater does not migrate the main InstanceID APIs for you. Rekey does.
It renames each obsolete call to the replacement Unity names, then follows the value through your code: the int local that held it becomes EntityId, then the field, the parameter, the return type and the Dictionary<int,...> or HashSet<int> it keys. Where a change would quietly alter behaviour, it stops and tells you why.
Measured on Unity 6000.5.7f1 A test project with pre-6.5 caches, an object pool and editor lookups: Unity refused to compile it. rekey fix made 22 rewrites in 3 files over 4 rounds. Unity then compiled it with 0 errors, and a behaviour check on the migrated code passed (lookups, pool counts, editor resolves).
A second project full of shapes that must not be touched: serialized int fields, PlayerPrefs.SetInt, arithmetic on ids, GetHashCode.
AI disclosure, as the store page states it: AI Assisted, Code, Graphics
Paid · Get it on itch.io. Files, screenshots and the full description are on the store page.