Scribunto

Scribunto is a MediaWiki extension that adds a Lua scripting engine and a module system to MediaWiki. It enables authors to implement template logic in Lua rather than in complex wikitext templates, improving maintainability and rendering performance for repetitive tasks. The extension provides a sandboxed Lua interpreter and a modular environment in which code is organized into modules stored in the Module: namespace. Template authors invoke module functions using the #invoke parser function, for example: {{#invoke:MyModule|MyFunction|arg1|arg2}}. Functions return strings, numbers, or tables that templates can render.

Modules can access a built-in mw library to interact with MediaWiki data and utilities, such as page titles, page content, and formatting helpers. This enables tasks such as data processing, generating complex outputs, and retrieving page metadata without embedding all logic directly in each template.

Installation requires adding the Scribunto extension to the MediaWiki server and enabling it in LocalSettings.php. After installation, contributors create Module:... pages containing Lua code. Submodules may be organized under Module:Foo/Bar and invoked accordingly.

Security controls enforce a sandbox with restricted I/O and resource usage to protect the wiki server from untrusted code. The extension provides APIs to access wiki data while isolating the Lua environment from direct server access.

Impact and usage: Scribunto has become widely adopted on Wikimedia projects for infoboxes, navigation templates, and data-driven rendering. While it can greatly simplify template logic, it requires careful module design and performance considerations.