Recomendation for a proxy server with good security?

[Jose Luis Rodriguez Garcia <joseyluis%gmail.com@localhost>]

I am looking for  a proxy web server designed to be sure, with minimal
security bugs.

I don't need especial features as cache, performance, etc. I want to
be it simple

HTTP and HTTPS is enough, and it will be used mainly for download
patches (yum, etc)

I tried http-gw from the toolkit of TIS, but it seems that it isn't
available anymore and the license is restrictive. It is for give
service on a hosted server of a customer.

It would be nice that it is in pkgsrc, but other options are good.