WordPress, a Cron job and Plugins

Greetings

I know of wp_schedule_event, and I’m actually using it for the plugin I’m coding.

The problem I’m having is that I’d like a function in my plugin to run, even if no one visits the site. The reason is that I want to make it run during the night, so it’s all up and ready to go after that.

My function runs for some time, and post new posts into the website, refreshing older ones… and while that occurs, the website seems down and acts weirdly (images not showing because the script hasn’t finished loading, etc).

Any ways I can call my function through a cron job that would run during the night, and still be able to use WP built-in function?

Regards,