Extensions are the primary way to add functionality to ComfyUI. They can be custom nodes, custom nodes that render widgets (UIs made with javascript), ComfyUI shell UI enhancements, and more. This documentation covers everything you need to know about understanding, using, and developing extensions.

Documentation Structure

Development Guide - How to develop extensions, including:
- Extension architecture and terminology
- How extensions load (backend vs frontend)
- Why extensions don't work in dev server
- Development workarounds and best practices
Core Extensions Reference - Detailed reference for core extensions:
- Complete list of all core extensions
- Extension architecture principles
- Hook execution sequence
- Best practices for extension development

Quick Links

Key Concepts

Extension: Umbrella term for any code that extends ComfyUI
Custom Nodes: Python backend nodes (a type of extension)
JavaScript Extensions: Frontend UI enhancements
Core Extensions: Built-in extensions bundled with ComfyUI

Common Tasks

External Resources

Need Help?

Check the Development Guide for common issues
Review Core Extensions for examples
Visit the ComfyUI Discord for community support