Implementations of the present disclosure provide an input method editor (IME) extension framework for extending the functionality of (IMEs). In some implementations, a user input into a user interface of an (IME) is received and is provided to a script engine. A script is selected from a plurality of scripts electronically stored in a script repository. The user input is processed through the script using the script engine to generate one or more candidates, and the one or more candidates are provided to an (IME) engine. In some implementations, a script file is received, the script file being executable by an (IME) system to generate one or more candidates based on a user input into the (IME) system. The script file is electronically stored in a central registry, the central registry including a plurality of scripts, and the plurality of scripts are published for download to and installation on a user device, the user device including the (IME) system.