XAO Suite is a set of perl modules created primarily for building dynamic, database driven web sites. It includes object oriented database layer that completely hides SQL yet is still efficient enough; web templating language strongly separating code and templates; etc — see specific modules descriptions for details and self-source page for a syntax sample.
XAO Suite has been in active development since 2000 (and is actually based partially on even earlier code, as detailed on the credits page). Practically right from the beginning the suite was not only developed, but actually used to deploy web sites — the code is sufficiently battle-tested and stable.
The easiest way to try XAO Suite might by using a pre-packaged docker container. It includes basic dependencies and can run a XAO site from any operating system capable of running docker containers.
Run a sample site by executing the command below and then pointing your browser to http://localhost:8080/
docker run -p 8080:80 amaltsev/xao-web