Authentication

The way I use auth libraries like ion_auth is to use my own library, say users_library, and all my controllers call the users library with things like check_user_login_status or do_login or do_logout, as well as non auth related like get_user_name or get_full_user_details etc. That library, and that one alone calls the auth library like ion_auth to take advantage of the already well written and well tested code. However, should I need or want to change auth libraries, I only have to alter that one file, the user_library, to deal with the different auth library.

Open source libraries are often abandoned as the original owners move on, or lose interest in maintaining it. Doing it the way above means that future changes are limited to just one file.