Using Selenium without a standalone server

I'm currently trying to create test cases for a web page that I've been developing. I am using PHP to write test cases to interact with Selenium. My current goal is to make these tests work without having to create a server in the background and I was wondering how to do this if anyone could please walk me through a plausible method of realising this. I have looked through some composer packages like this one https://packagist.org/packages/facebook/webdriver but I haven't been able to find a solid way to run it without a standalone server. Any and all help would be appreciated!