Merge pull request supabase#15949 from supabase/j0/add_doc_on_smtp

feat: add doc on setting up custom smtp provider

Author: J0

apps/docs/components/Navigation/NavigationMenu/NavigationMenu.constants.ts

@@ -477,6 +477,7 @@ export const auth = {
       url: undefined,
       items: [
         { name: 'Enable Captcha Protection', url: '/guides/auth/auth-captcha' },
+        { name: 'Configuring Custom SMTP', url: '/guides/auth/auth-smtp' },
         { name: 'Managing User Data', url: '/guides/auth/managing-user-data' },
         { name: 'Multi-Factor Authentication', url: '/guides/auth/auth-mfa' },
         { name: 'Row Level Security', url: '/guides/auth/row-level-security' },

apps/docs/pages/guides/auth/auth-smtp.mdx

@@ -0,0 +1,39 @@
+import Layout from '~/layouts/DefaultGuideLayout'
+
+export const meta = {
+  id: 'auth-smtp',
+  title: 'Configure a Custom SMTP',
+  description: 'Moving towards production: Configuring a custom SMTP provider',
+}
+
+# Auth SMTP
+
+At present, you can trial the Supabase platform by sending up to **4** emails per hour via the built-in service. The default email service as a whole is offered on a best effort basis: we will do our best to maintain it and will review usage of the service on a regular basis to see if the email service should be continued.
+
+As you progress toward production, you may find yourself wanting for a custom SMTP service in order to increase your limits. A custom SMTP server will allow you to set your own cap on the number of emails sent per hour.
+
+Beyond rate limits, an SMTP server might also help with:
+
+- Deliverability and Reputation Management
+- Scalability
+- Analytics and Tracking
+- Compliance and Anti Spam measures
+
+## How to Set up SMTP
+
+Head over to the [Auth Settings Page](https://supabase.com/dashboard/project/_/settings/auth) and hit "Enable Custom SMTP" under the SMTP Provider section.
+
+Fill in fields below with the relevant details obtained from your custom SMTP provider:
+
+![SMTP settings](/docs/img/guides/auth-smtp/smtp.png)
+
+### SMTP Providers
+
+You can use Supabase Auth with any major SMTP provider of your choosing. Some SMTP providers you could consider using are:
+
+- [Twilio SendGrid](https://docs.sendgrid.com/for-developers/sending-email/integrating-with-the-smtp-api)
+- [AWS SES](https://docs.aws.amazon.com/ses/latest/dg/send-email-smtp.html)
+- [Resend](https://resend.com/docs/dashboard/emails/introduction)
+
+export const Page = ({ children }) => <Layout meta={meta} children={children} />
+export default Page

apps/docs/pages/guides/platform/going-into-prod.mdx

@@ -40,8 +40,8 @@ After developing your project and deciding it's Production Ready, you should run
 ## Availability
 
 - Use your own SMTP credentials so that you have full control over the deliverability of your transactional auth emails (see Settings > Auth)
-  - you can grab SMTP credentials from any major email provider such as SendGrid, AWS SES, etc.
-  - The default rate limit for auth emails provided by Supabase is 30 new users per hour, if doing a major public announcement you will likely require more than this.
+  - you can grab SMTP credentials from any major email provider such as SendGrid, AWS SES, etc. You can refer to our [SMTP guide](/docs/guides/auth/auth-smtp) for more details.
+  - The default rate limit for auth emails when using a custom SMTP provider is 30 new users per hour, if doing a major public announcement you will likely require more than this.
 - If your application is on the free plan and is **not** expected to be queried at least once every 7 days, then it may be paused by Supabase to save on server resources.
   - You can restore paused projects from the Supabase dashboard.
   - Upgrade to Pro to guarantee that your project will not be paused for inactivity.