Diazo, previously named xdv, is a general-purpose, open source website theming tool.
Diazo creates a separation between theme pages (static HTML) and transformation rules (Diazo's own domain specific language based in XML), allowing web designers to work on templates in plain HTML, without knowledge of XSLT or special template-related codes.
Nginx has an XSLT processor,[3] but, as of March 2012, it requires the unthemed website (the content) to use strict XHTML.
A major motivation for the name change was to reduce ambiguity, as the XDV name was used by both collective.xdv (a Plone-specific theming package, now called plone.app.theming) and by the stand-alone XDV tools (now called Diazo).
Advanced features include: conditions based on content nodes or paths, with grouping and nesting; multiple, conditional themes; modifying the theme or content on the fly; inline XSL directives; Doctype changes; XInclude protocol.