Sending mass emails efficiently and reliably is a common challenge for developers and businesses. Through my recent project, I built a scalable mass email service leveraging AWS services like SES, SQS, Lambda, S3, and CloudWatch. This article will walk you through the project, from the architecture to the step-by-step implementation. The source code and resources can be found in the this GitHub repository https://github.com/Dandi-Pangestu/aws-mass-email-service.

Why This Project?

Email campaigns can be tricky to scale, especially when handling high volumes, ensuring deliverability, and maintaining reliability. This project aims to address those challenges by leveraging Amazon Web Services (AWS), enabling a robust and scalable solution for mass email campaigns.

Architecture Overview

The architecture for this project is designed to ensure scalability, fault tolerance, and monitoring. Below is the architecture diagram:

High Level Architecture

Components in the Architecture

  1. Amazon SES (Simple Email Service): Responsible for sending emails.
  2. Amazon SQS (Simple Queue Service): Adds a queue to handle email requests asynchronously.
  3. AWS Lambda: There are two lambda functions in this project. The first one is for receiving event notification from s3 and then extract the recipient email addresses which exists in the csv file. The second one is for sending each email address to Amazon SES.
  4. Amazon S3: Stores recipient email addresses in CSV form.
  5. Amazon CloudWatch: Amazon CloudWatch is utilized in this project for application logging, enabling the monitoring of both success and error events during the email processing pipeline. It ensures transparency and provides actionable insights by capturing logs for successfully executed processes as well as errors that might occur, making debugging and system optimization more efficient.

Real-World Use Cases

This scalable AWS mass email service can be applied in various real-world scenarios, such as:

  1. Marketing Campaigns: Businesses can use this service to send promotional emails to thousands, tens of thousands, or even millions of users. The architecture ensures that the emails are sent reliably without overwhelming the system.
  2. Transactional Emails: E-commerce platforms can use this setup to send order confirmations, shipping updates, and other transactional emails. The asynchronous processing ensures that alerts are sent promptly.
  3. Notifications System: Organizations can send alerts to their users, such as password reset emails, security notifications, or event reminders. The monitoring capabilities of CloudWatch make it easy to track the success and failure rates of such notifications (https://docs.aws.amazon.com/ses/latest/dg/monitor-using-event-publishing.html).
  4. Newsletter Distribution: Content creators and publishers can distribute newsletters to their subscribers efficiently, with the ability to customize email templates stored in S3.
  5. Community Announcements: Non-profits and community organizations can send announcements to their members, ensuring that the communication reaches everyone in the network.

Pricing Prediction for AWS Services

Before implementing any project, understanding the potential costs is crucial. Here's a breakdown of the pricing for the main AWS services used in this project.

  1. Amazon SES
    • Free Tier: 62,000 emails per month when sent from an Amazon EC2 instance.
    • Pricing Beyond Free Tier: $0.10 per 1,000 emails sent.
    • Additional Costs: $0.12 per GB of attachments.
  2. Amazon SQS
    • Free Tier: 1 million requests per month.
    • Pricing Beyond Free Tier: $0.40 per 1 million requests (for standard queues).
    • Data Transfer Costs: Additional charges apply for data transfer out beyond the free tier.
  3. AWS Lambda
    • Free Tier: 1 million free requests and 400,000 GB-seconds of compute time per month.
    • Pricing Beyond Free Tier:
      • $0.20 per 1 million requests.
      • $0.00001667 per GB-second of compute time.
  4. Amazon S3
    • Free Tier: 5 GB of standard storage.
    • Pricing Beyond Free Tier:
      • $0.023 per GB for the first 50 TB of standard storage.
      • $0.005 per 1,000 PUT, COPY, POST, or LIST requests.
      • $0.0004 per 1,000 GET and SELECT requests.

Cost Example
For a campaign sending 100,000 emails monthly with attachments:

  1. SES: $10 for emails + $1.20 for 10 GB of attachments.
  2. SQS: $0.40 for 1 million requests (assuming 1 email = 1 request).
  3. Lambda: $0.60 for 3 million requests (batch processing) and 2.5 GB-seconds of compute.
  4. S3: Approximately $0.50 for 20 GB of templates and logs.

Estimated Total Monthly Cost: ~$12.50 (excluding free tier).
Costs can vary depending on usage, so always use the AWS Pricing Calculator (https://calculator.aws/#/) for accurate predictions.

Step-by-Step Implementation

Instead of re-explaining the implementation process here, I've detailed each step in the tutorials section (https://github.com/Dandi-Pangestu/aws-mass-email-service/tree/main/tutorials) of the GitHub repository. The tutorials provide:

  • Detailed step-by-step instructions on setting up the AWS services.
  • Code snippets for configuration and deployment.
  • Examples of how to test the service.

Challenges and How They Were Solved

  1. Handling Large Email Volumes: By using SQS and Lambda, the system can process emails in batches, avoiding bottlenecks.
  2. Improving Email Deliverability: Optimizing SES settings, such as ensuring SPF, DKIM, and DMARC records, helped improve email deliverability rates.
  3. Monitoring and Debugging: CloudWatch provided actionable insights into system health and email delivery metrics, making it easier to identify and resolve issues.

What Makes This Solution Scalable?

The decoupled architecture allows each component to scale independently. For example:

  • SQS ensures reliable queuing of email requests.
  • Lambda scales out automatically to process messages in parallel.
  • SES handles high email volumes efficiently, adhering to AWS limits.

Conclusion

This project demonstrates how AWS services can be combined to build a powerful, scalable mass email service. Whether you're a developer or a business owner, this solution can help streamline your email campaigns while ensuring reliability and scalability. You can explore the project further in the GitHub repository https://github.com/Dandi-Pangestu/aws-mass-email-service. Feel free to adapt it to your needs and share your feedback!

Next Steps

Future improvements could include:

  • Adding a user-friendly interface for managing email campaigns.
  • Implementing analytics for campaign performance.
  • Add functionality to handle transactional emails, allowing the system to send emails triggered from any external source or application.

If this article inspired or helped you in any way, please leave a ❤️ and share it with your network. Happy coding!