title:: Using Extensions summary:: Using Extensions categories:: Internals related:: Guides/WritingUGens, Guides/UsingQuarks, Guides/WritingClasses SC supports extensions to its class library, documentation, and server UGen plugins. Extensions should be packaged as a single folder containing all three (for convenient addition or removal), or any combination, which can then be placed in platform-specific extension directories in order to be included. section:: Platform Specific Directories You can install extensions simply by copying the extensions to the following location. There are different directories for per-user and system-wide extensions that apply to all users.. The locations can be obtained by running code::Platform.userExtensionDir:: and code::Platform.systemExtensionDir::. Typical user-specific extensions directories: table:: ## macOS || ~/Library/Application Support/SuperCollider/Extensions/ ## Linux || ~/.local/share/SuperCollider/Extensions/ :: Typical system-wide extension directories: table:: ## macOS || /Library/Application Support/SuperCollider/Extensions/ ## Linux || /usr/share/SuperCollider/Extensions/ :: section:: How Extensions Folders Should be Organised Class files and UGen plugins are recognised by their file extensions. Anything placed within a folder named teletype::ignore/:: (case insensitive) will be ignored when compiling the class library or loading plugins. Here is an example folder layout: teletype::MyExtension:: tree:: ## teletype::classes:: tree:: ## teletype::myClass.sc:: ## teletype::myUGens.sc:: :: ## teletype::plugins:: tree:: ## teletype::myUGenPlugins.scx:: :: ## teletype::HelpSource:: tree:: ## teletype::Classes:: tree:: ## teletype::MyClass.schelp:: ## teletype::MyUGen1.schelp:: ## teletype::MyUGen2.schelp:: :: ## teletype::Guides:: tree:: ## teletype::MyExtensionGuide.schelp:: :: :: ::