InBucket for local development in the Next.js Supabase Starter Kit

When developing locally, Supabase uses InBucket and Mailpit (depending on which version you're running) to capture emails sent during development. This allows you to test email functionality without actually sending emails to real addresses.

Makerkit also uses InBucket/Mailpit for sending non-authentication emails, such as team invitations and account deletion confirmations.

What is Mailpit?

Mailpit is a disposable email service that captures all emails sent during local development. It's particularly useful for testing:

• Email verification flows
• Password reset emails
• Team invitations
• Notification emails
• Any other transactional emails

Accessing Mailpit

When running Supabase locally, Mailpit is automatically available at:

http://localhost:54324

You can view any captured emails by:

1. Going to http://localhost:54324
2. Finding your test email in the list of received messages

Common Use Cases

1. Email Verification

When testing user signup:

1. Create a new account using any email address
2. Go to InBucket/Mailpit at http://localhost:54324
3. Find the verification email
4. Click the verification link or copy the verification code

2. Password Reset

To test password reset flows:

1. Request a password reset using any email
2. Check InBucket/Mailpit for the reset email
3. Use the reset link or code to complete the process

3. Team Invitations

When testing team invites:

1. Send an invitation to any email address
2. Check Mailpit for the invitation email
3. Use the invitation link to accept

Mailpit vs Production Emails

Remember that Mailpit is for development only. In production:

1. Configure a proper email service provider (Resend, SendGrid, etc.)
2. Set up proper email authentication (SPF, DKIM)
3. Use production-grade SMTP settings
4. Monitor email deliverability

Using a different email provider during local development

If you want to use a different email provider, switch the environment variables at apps/web/.env.development:

EMAIL_SENDER=test@makerkit.dev
EMAIL_PORT=
EMAIL_HOST=
EMAIL_TLS=
EMAIL_USER=
EMAIL_PASSWORD=

NB: Supabase authentication emails will still be sent using InBucket/Mailpit.

Conclusion

InBucket/Mailpit are valuable tools for local development, allowing you to:

• Test email flows without sending real emails
• Iterate quickly on email templates
• Debug email-related issues
• Develop with confidence

Remember to switch to a proper email provider when deploying to production!