Modules in a backend project

📘What it really is

• Everything from Module 29 applies: ES modules, import/export, one subject per file, dependencies pointing one way.

• A typical structure for an API (Module 43 explains each layer):

enquiries-api/
  src/
    server.ts        starts the server
    app.ts           sets up the app and routes
    routes/          addresses and methods
    services/        business rules
    data/            storage
    config.ts        settings
  tests/
  package.json
  tsconfig.json
  .env.example

• Running TypeScript in development: Node.js can run .ts files directly (Module 27); node --watch src/server.ts restarts on every save. Run tsc --noEmit to check types.

• For production, many teams compile to JavaScript with tsc (into dist/) and run that, or use a bundler. Either way, check types in CI (Level 6).

• Scripts:

"scripts": {
  "dev": "node --watch src/server.ts",
  "check": "tsc --noEmit",
  "test": "node --test \"tests/**/*.test.ts\""
}