Create separate directories for config, routes, and services to organize logging, API endpoints, and the core Sinch interaction logic respectively.

ESM (ECMAScript Modules) is the standard module system for JavaScript and is required by some modern libraries like node-fetch v3+. Use .mjs extensions or "type": "module" in package.json.

Implement robust input validation, sanitize user inputs, and use environment variables to manage sensitive credentials, ensuring the .env file is added to .gitignore.

Use the Sinch Batches API endpoint within a Node.js Express app. This allows you to send a single message to multiple recipients efficiently, perfect for notifications and marketing campaigns.

The Sinch Batches API endpoint is a RESTful endpoint designed for sending the same SMS message content to multiple recipients in a single API request, improving efficiency over individual messages.

Node-fetch brings the familiar browser fetch API to Node.js, providing a lightweight and standard way to make HTTP requests to REST APIs like Sinch.

Use the Batches API for scenarios like sending notifications, running marketing campaigns, or any situation needing mass SMS distribution to multiple recipients simultaneously.

Yes, you can use a provisioned phone number or an approved Alphanumeric Sender ID as the sender of your SMS messages with Sinch. Configure this in your Sinch dashboard.

Initialize a Node.js project with npm, enable ESM, install Express, dotenv, node-fetch, and winston, and create the necessary project file structure.

Dotenv loads environment variables from a .env file into process.env, allowing you to store sensitive credentials like API keys securely outside your source code.

Implement try/catch blocks in your service layer to handle API errors and retry mechanisms for transient errors, using Winston to log errors for debugging and monitoring.

Log in to your Sinch Dashboard, navigate to SMS > APIs, and find your Service plan ID and API token under 'Your API Credentials'. Ensure you select the correct region.

The correct SINCH_REGION_URL for the US region is https://us.sms.api.sinch.com. Ensure you use the correct URL based on your Sinch account region to avoid authentication errors.

You'll need Node.js and npm installed, a Sinch account with a Service Plan ID and API token, a provisioned phone number or Alphanumeric Sender ID, and basic knowledge of JavaScript, Node.js, and REST APIs.

Winston is a logging library used for structured logging, allowing you to categorize logs by levels (error, warn, info, etc.) and output to different transports like the console or files.