Wikipedia
WackoWiki is a lightweight, expandable, multilingual wiki engine based on WakkaWiki. The software is written in PHP, and uses MySQL to store pages. WackoWiki has an advanced editor with support for multiple languages, easy installer, many localizations, email notification on changes/comments, several cache levels, design themes (skins) support, XHTML compliance, page rights ( ACLs), and page comments. WackoWiki is licensed under BSD.
WackoWiki is developed mainly by Russian programmers, but it is not a Russian-only engine. At the moment it supports Bulgarian, Danish, Dutch, English, Estonian, French, German, Greek, Italian, Spanish, Polish, Portuguese, and Russian languages. WackoWiki was forked from the WakkaWiki engine in 2003 when Hendrik Mans and Carlo Zottmann, the original developers, abandoned it.
WackoWiki allows the use of full HTML capabilities, and uses the SafeHTML parser (written by the same developers) to strip out potentially dangerous content ( JavaScript, etc.) which may cause cross-site scripting vulnerabilities.
Developers of WackoWiki also created WikiEdit, a JavaScript multi-language editor that generates wiki markup using keyboard shortcuts and toolbar buttons. WikiEdit also supports autoindenting (and increments in ordered lists).
WackoWiki is widely used in Russia as a wiki-engine, and by many IT companies as a lightweight CMS and a knowledge management system. It shares several modules, developers, and a bugtracker with the NPJ engine.
The latest version is R5.4.0, released on 18 April 2014.