Gjs

GJS, short for GNOME JavaScript, is the GNOME project that provides a JavaScript runtime and bindings for GNOME libraries. It uses Mozilla's SpiderMonkey as the JavaScript engine and offers GObject introspection-based bindings to GNOME APIs, enabling developers to write GNOME applications and extensions in JavaScript. It is widely used by GNOME Shell and various GNOME applications.

GJS exposes GNOME libraries to JavaScript through a module system, allowing code to import modules such as GLib, Gio, and GObject. JavaScript can create and manipulate GObject-based objects, connect to signals, and use GNOME asynchronous APIs. The bindings expose the rich GNOME platform in a way familiar to JavaScript developers, supporting typical scripting workflows within the GNOME environment.

Historically, GJS emerged to support JavaScript-based user interfaces and extensions within the GNOME platform. Over time it has evolved with new bindings and engine updates to keep pace with GNOME releases, maintaining its role as the primary scripting layer for GNOME components and extensions.

Architecture-wise, the core is a C library that embeds the JavaScript engine and bridges it to GNOME libraries via GObject Introspection. It integrates with GLib’s main loop, enabling asynchronous operations and event-driven programming common in GNOME applications. The design emphasizes dynamic bindings to GNOME APIs, with careful management of object lifetimes, signals, and type conversions between JavaScript and C.

GJS is free and open-source software released under the GNU Lesser General Public License. It is distributed with GNOME and available in major Linux distributions as part of the GNOME technology stack.