This app was requested in the past (at least once, but not the topic is locked) and I was thinking to encourage this request because of the great advantages this app offers.
At this moment, PortableApps offers XAMPP, which is great, but mostly safe to use in a closed network that has enough protection from outside unauthorized access. Of course, it can be configured to offer more security, but as it's primary intended for development, the out-of-the-box experience offers little to no protection, which means that a public website ran from xampp (eg, you want to allow access to your client to see it, or whatever other reason), without having the proper settings made to xampp exposes you to considerable risk.
On the other hand, there is Uniform Server ( http://www.uniformserver.com/ ) which is a fairly small and easy to configure platform that offers all the benefits of XAMPP, but is ready for "production" to say so. I switched from xampp to uniform server few years ago and since then I had no reason to turn back. I found absolutely no restriction or issue that would convince me to return to xampp for no matter what reason.
So, for the reasons above, I believe that Uniform Server should find its way into PortableApps.
Please let me what you think about this request.