Introduction

An overview of the Klyx extension system and its APIs

Klyx is a mobile code editor for Android with a plugin system that lets you extend its capabilities. Plugins can add custom screens, toolbar actions, file openers, terminal sessions, language servers, and more.

This documentation covers everything you need to build, bundle, and distribute plugins for Klyx.

How plugins work

Plugins are Android APKs packaged into .klyx bundles. Klyx loads them at runtime. Each extension declares metadata in a plugin.json file and implements the KlyxPlugin interface. The app manages the full lifecycle: loading, starting, stopping, and unloading.

Architecture overview

Every plugin starts with a plugin.json manifest and a class that implements KlyxPlugin. At runtime, Klyx injects services into your plugin through property delegates. You register screens, toolbar actions, file openers, and event subscribers during the lifecycle hooks.

Concept	Description
KlyxPlugin	Interface your entry class implements. Defines onLoad, onStart, onStop, onUnload
PluginDescriptor	Metadata: id, name, version, entry class, author, permissions
PluginService	Global services available to all plugins (screens, toolbar, settings, etc.)
PluginContext	Per-plugin runtime context with access to app, event bus, and coroutine scope
.klyx bundle	The distribution format: an archive containing APK + metadata

What you can build

• Custom screens and UI panels
• Toolbar actions with icons
• Custom file openers for new file types
• Terminal session management
• Language server integrations
• Background process execution
• Event-driven features responding to file opens, terminal events, and more
• Theme-aware UI using Klyx’s color system and typography
• And more

Prerequisites

Before you begin, make sure you are comfortable with the following technologies and concepts:

• Kotlin - for implementing core plugins logic
• Android Fundamentals - e.g. Activities, Services, Context, …

Next steps

Quickstart

Build your first plugin in minutes

Creating an Extension

Step-by-step guide to creating a Klyx extension

API Reference

Complete API reference for all Klyx extension APIs