Alter view and pager to display more items per page programmatically

I have 1 codebase for a multisite install. I needed to change the number of items per page on every page and didn't want to use the view ui and change every view. So I looked for a way to do this programmatically.

As it turns out this is quite simple.

I used hook_views_pre_build() to do this:

/**
 * Implements hook_views_pre_build ()
 */
function MODULENAME_views_pre_build(&$view) {
  if($view->name == "name_of_your_view") {
    $view->items_per_page = 30;
  }
}