Passes on path

Let's say I have this online at `http://example.com/proxy` and I'm using this to forward to `http://api.com/api`. When I make a JavaScript fetch request to `http://example.com/proxy`, the proxy ultimately requests `http://api.com/api/proxy`, resulting in a 404. Is there some sort of filtering that I should be doing to prevent this path from being appended?

I'm not doing much beyond the example in the readme.