Email infrastructure, handled

Transactional and marketing email via REST API, SMTP, or MCP. Built for developers and AI agents. Up to 75% cheaper than Resend, SendGrid, and Postmark.

EU Data Residency— Data centers in Germany and Finland. GDPR compliant.

$ curl -X POST https://api.poststack.dev/api/emails \
  -H "Authorization: Bearer sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "from": "hello@yourdomain.com",
    "to": "user@example.com",
    "subject": "Welcome aboard!",
    "html": "<h1>Welcome!</h1>"
  }'

Everything you need for email

REST API, SMTP relay, templates, contacts, broadcasts, analytics, and built-in mailboxes. One platform.

Developer First

One POST request to send an email. TypeScript, Python, and Go SDKs. MCP server for Claude, Cursor, and other AI assistants. Webhooks for every event.

Deliverability Built In

SPF, DKIM, and DMARC set up automatically when you add a domain. Bounce and complaint handling runs in the background.

Real-Time Analytics

Opens, clicks, deliveries, bounces, and complaints — tracked in real time. Live dashboard and webhook events.

Templates

Handlebars variables and React Email support. Preview, version, and ship without redeploying.

Contacts & Broadcasts

Import contacts, build audiences, and send broadcasts. Segment by tags or custom fields. Scheduling and one-click unsubscribe included.

Mailboxes & Webmail

Full email hosting with built-in webmail. Create mailboxes on your domain, read and send from the dashboard, or connect any email client via IMAP or POP3.