jan/core/CONTRIBUTING.md

Contributing to Jan Core

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TypeScript SDK providing extension system, APIs, and type definitions for all Jan components.

Key Directories

• /src/browser - Core APIs (events, extensions, file system)
• /src/browser/extensions - Built-in extensions (assistant, inference, conversational)
• /src/types - TypeScript type definitions
• /src/test - Testing utilities

Development

Key Principles

1. Platform Agnostic - Works everywhere (browser, Node.js)
2. Extension-Based - New features = new extensions
3. Type Everything - TypeScript required
4. Event-Driven - Components communicate via events

Building & Testing

# Build the SDK
yarn build

# Run tests  
yarn test

# Watch mode
yarn test:watch

Event System

// Emit events
events.emit('model:loaded', { modelId: 'llama-3' })

// Listen for events
events.on('model:loaded', (data) => {
  console.log('Model loaded:', data.modelId)
})

Testing

describe('MyFeature', () => {
  it('should do something', () => {
    const result = doSomething()
    expect(result).toBe('expected')
  })
})

Best Practices

• Keep it simple
• Use TypeScript fully (no any)
• Write tests for critical features
• Follow existing patterns
• Export new modules in index files

Dependencies

• TypeScript - Type safety
• Rolldown - Bundling
• Vitest - Testing