Introduction

What is uSketch?

uSketch is a real-time collaborative whiteboard application built for the browser. Version 2 is a ground-up rewrite that adopts a plugin-first architecture — every drawing feature is implemented as a plugin.

What is the Plugin SDK?

The Plugin SDK is the public surface of @edv4h/usketch-shared and @edv4h/usketch-core. It provides:

• UsketchPlugin — the interface every plugin implements.
• PluginContext — the registries and services available inside setup().
• Type definitions for shapes, tools, layers, commands, events, and transient objects.

Architecture at a Glance

createApp({ store, plugins })
  │
  ├─ Register each plugin in PluginRegistry
  ├─ Call plugin.setup(ctx) sequentially
  │   ├─ Register shapes  → ShapeRegistry
  │   ├─ Register tools   → ToolRegistry
  │   ├─ Register layers  → LayerManager
  │   ├─ Register commands → CommandRegistry
  │   └─ Subscribe events → EventBus
  │
  └─ Mount React tree
      ├─ Canvas (renders layers by order)
      ├─ Toolbar (shows registered tools)
      └─ PropertyPanel (shape-specific UI)

A plugin is a plain object with an id, a name, and a setup function. That’s it.

Next Steps

• Quick Start — build a minimal plugin in 5 minutes.
• Dev Setup — clone the monorepo and run locally.