I'm building a small SaaS. how do I avoid building email infrastructure?

If you want to avoid building email infrastructure, the short answer is: don’t run your own SMTP/sendmail stack—use a transactional email provider and only build the app logic around it.

Easiest path

Pick a provider like:

• Postmark – great for transactional email, very reliable
• SendGrid – broad feature set, common choice
• Amazon SES – cheaper, more manual setup
• Mailgun – developer-friendly
• Resend – modern API, good DX for startups

These handle the hard parts:

• SMTP delivery
• IP reputation / warmup
• DKIM, SPF, DMARC guidance
• bounce handling
• spam complaints
• retries / queueing
• deliverability monitoring

What you should build instead

In your SaaS, you usually only need:

1. A mail-sending service layer
   • sendWelcomeEmail(user)
   • sendPasswordReset(user)
   • sendInvoice(user)
2. Templates
   • HTML + text versions
   • variables for name, links, etc.
3. Webhook handler
   • process bounces, complaints, unsubscribes, delivery events
4. Audit/logging
   • record what was sent and when
5. Domain authentication
   • set up SPF, DKIM, DMARC for your domain

Recommended architecture

• Your app emits an event: user.registered
• A background job picks it up
• Your mail service calls the provider API
• Provider sends email and posts events back to your webhook
• You store delivery status in your DB

This keeps email out of your core app flow and avoids blocking requests.

Even less to build

If you want to minimize work further, use:

• A hosted template system if the provider offers it
• A job queue like Sidekiq, BullMQ, Celery, SQS, etc.
• A dedicated email package in your framework, but only as a thin wrapper

What not to do

Avoid:

• running your own Postfix/Exim server
• sending from your app server directly
• using a generic Gmail/SMTP account for production
• skipping domain authentication
• ignoring bounce/complaint events

Practical startup recommendation

For a small SaaS, I’d do:

• Resend or Postmark for simplicity
• Background jobs for sending
• Webhook endpoint for events
• SPF + DKIM + DMARC on your sending domain

If cost is the main concern, use Amazon SES.
If developer experience matters most, use Resend or Postmark.

If you want, I can also give you:

1. a minimal email architecture,
2. a provider comparison table, or
3. a code example in Node/Python/Rails.