# vSMTP rule engine

vSMTP server is built with a runtime also called `rule engine`.
This runtime can execute code provided in our superset of the
<https://rhai.rs> language.

The viridIT scripting language (vsl) is a simple language that allow
you to define `rules` and `object` to control the traffic on your MTA.

Further details on the official book of vSMTP: <https://vsmtp.rs/reference/vSL/vsl.html>