Programming languages

There are many programming languages associated with MediaWiki, including:

PHP - the primary language that MediaWiki was originally written in, and which most new code in MediaWiki uses
JavaScript - language used for many important components of MediaWiki, notably VisualEditor, Parsoid, and all Gadgets, not to mention most code delivered to the browser via ResourceLoader for execution.
Lua - language of scripts executed via Scribunto.
Ruby - the base language for the browser test engine (Cucumber) and is used in Puppet deployment system.
Python - used in development of many tools such as Pywikibot.
Many client libraries available at API:Client code , including C++, C# (.NET), Java, OCaml, Objective-C, Perl, Python, R, and Ruby

Coding Conventions