IISpeed is a native c++ module which implements a port of ngx_pagespeed to Microsoft IIS. It ports the PageSpeed automatic libraries to Windows, and implements a fully asynchronous rewriting filter on top.

The project started in 2012 , as We-Amp set out to make a port to NGINX (ngx_pagespeed) happen in a partnership with Google. As of 2017 mod_pagespeed has been in the Apache incubator where We-Amp still tends to it.