What is the difference between Notify and building my own email delivery stack?

If by Notify you mean a managed email notification service, the main difference is:

Notify

A service that handles email sending for you.

Pros

• Fast to set up
• Handles retries, deliverability basics, bounce handling, templates, logs, and tracking
• Less infrastructure to maintain
• Good for transactional emails like OTPs, alerts, and receipts

Cons

• Less control over low-level delivery behavior
• Can be more expensive at scale
• Vendor dependency
• Limited customization compared to owning the stack

Building your own email delivery stack

You manage the whole pipeline yourself.

This usually includes:

• SMTP relay or sending servers
• IP/domain reputation management
• DKIM, SPF, DMARC
• Bounce processing
• Retry logic
• Queueing
• Template rendering
• Monitoring and analytics
• Abuse prevention and compliance

Pros

• Full control
• Potentially lower cost at very high volume
• More flexibility in routing, branding, and delivery logic

Cons

• Much more engineering and operational work
• Deliverability is hard
• Requires ongoing maintenance, monitoring, and tuning
• You own failures, spam issues, blacklisting, and compliance

Rule of thumb

Use Notify if you want to send emails reliably without building and operating mail infrastructure.

Build your own stack if:

• you have very high scale,
• very specific deliverability needs,
• or email is a core product capability and you can invest in the ops burden.

If you want, I can also compare Notify vs SendGrid/Mailgun/AWS SES specifically.