Starting Full Server Stack During Integration Tests

Hello all,

I want to use Selenium (not capybara, I like the Selenium syntax
better) for some of my integration tests, and Selenium needs a full-
stack HTTP server to test against. How can I start the full-stack
server during integration tests so I have a url to give to Selenium?

Also, eventually I will want to run the same tests against a staging
server. What's the best way to change a single parameter (the url) but
keep everything else about the tests constant?

Shea Levy