This directory contains code shared between frontend (browser) and backend (Deno).

• types.ts - TypeScript interfaces and types

  • Controller response format
  • Notion data structures
  • API request/response types

• utils.ts - Utility functions

  • Must work in both browser AND Deno
  • ❌ NEVER use Deno APIs (won't work in browser)
  • ✅ Only use standard JavaScript/TypeScript

• Define interfaces for data shared between layers
• Use clear, descriptive names (PascalCase)
• Document complex types with comments

• Test that functions work in both environments
• Avoid platform-specific APIs (Deno, Node, browser-only)
• Use pure functions when possible

// ✅ Good - works everywhere
export function formatDate(date: string): string {
  return new Date(date).toLocaleDateString();
}

// ❌ Bad - Deno-specific
export function readConfig() {
  return Deno.env.get('CONFIG'); // Won't work in browser!
}