ember-simple-auth

Version 7.0 introduced breaking changes, such as requiring explicit imports for session service and store, which adds migration overhead and potential confusion for upgraders, as noted in the upgrade guides.

Tightly coupled with Ember.js, making it unusable outside the Ember ecosystem and requiring deep familiarity with Ember's conventions and tooling.

Focuses solely on backend logic, leaving all UI implementation (e.g., login forms, error messages) to the developer, which increases initial setup effort compared to more opinionated solutions.

Requires creating multiple files (authenticators, session stores) and configuring route protection, which can be overkill for simple authentication needs and adds boilerplate.