Using Wordpress Admin with CodeIgniter Application

[eluser]Unknown[/eluser]
Hey guys,

I've tried doing some research on this topic, but I haven't found an exact solution that suits my needs yet.

Basically I'm building a website in CodeIgniter, but using WordPress for the site's blog. Now what I would like to do is find a way to use the WordPress admin for administration of my CodeIgniter application, as opposed to writing a custom administration system from scratch directly in CodeIgniter.

All the other posts on this subject that I could find talked about implementing WordPress directly into CodeIgniter, so that you can use WordPress functions in your CodeIgniter application. This doesn't help me, because in my case, I want to keep my CodeIgniter application independent. The only function I may wish to share between the two applications is the user authentication system, but that can be implemented later.

Any ideas on how I would go about doing this? My first thought is to create some sort of custom API in my CodeIgniter application, that I can access through a WordPress plugin. I'm not too sure how I would do that though, and how secure it would be. Nonetheless I'm open to all suggestions.

Thanks,
Scott