> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lettr.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

> Connect Lettr to platforms like Stripe, Supabase, WordPress, and Zapier for email delivery via SMTP, the HTTP API, or Edge Functions.

Integrate Lettr into third-party platforms and services. Each guide walks you through connecting Lettr for email delivery — whether through SMTP configuration, the HTTP API, or Edge Functions.

## Available Integrations

<CardGroup cols={2}>
  <Card title="Stripe" icon="stripe" href="/integrations/stripe">
    Send payment receipts, invoice emails, and subscription notifications
  </Card>

  <Card title="Supabase" icon="bolt" href="/integrations/supabase">
    Send auth emails and transactional messages from Supabase using Lettr
  </Card>

  <Card title="WordPress" icon="wordpress" href="/integrations/wordpress">
    Replace wp\_mail with Lettr for reliable email delivery from WordPress
  </Card>

  <Card title="Zapier" icon="bolt" href="/integrations/zapier">
    Automate email sending with 8,000+ apps — no code required
  </Card>
</CardGroup>

## Don't See Your Platform?

You can integrate Lettr with any platform that supports SMTP or HTTP APIs.

<CardGroup cols={2}>
  <Card title="SMTP Relay" icon="server" href="/quickstart/smtp/introduction">
    Connect any platform that supports SMTP credentials
  </Card>

  <Card title="HTTP API" icon="code" href="/api-reference/introduction">
    Send emails from any language or platform via REST API
  </Card>
</CardGroup>

<Info>
  Need help integrating with a specific platform? [Contact support](mailto:support@lettr.com) and we'll help you get set up.
</Info>