Explore running JavaScript on the server with Node, managing npm packages, and using async/await with fetch to access APIs, plus object and array techniques and Moment basics.

Explore customizations in the pet hotel app by tailoring user roles, permissions, and dashboards, and configuring settings, themes, and client access to bookings and pets.

Change the user rules to manager, employee, and pet owner across backend and frontend, adjust permissions and labels, and implement role checks with database resets when needed.

Validate pet deletion by counting related bookings in the bookings repository and blocking delete when a booking exists, with internationalized error messaging and unit tests.

Pet owners can only edit bookings when the status is booked, and managers can edit to any status, with validations ensuring bookings move from booked to canceled only.

Apply conditional rendering in the booking form to show notes and photos in progress, and cancellation notes and receipts only when completed; group with a React fragment for clarity.

Implement role-based access control so only managers can register employees and other managers, with backend and frontend permission checks, validations, and UI changes to enforce secure role management.