Customer.io (Email Marketing) and Mailgun (Transactional Email) are commonly run side-by-side. When teams operate both, the question that follows is always how to keep the two in sync without re-entering data twice.
What people typically integrate
- Keep records in sync between the two systems so teams stop re-entering data
- Trigger downstream actions in one tool from events in the other
- Surface relevant context from one system inside the other so users don't switch tabs
- Aggregate data into shared reporting without manual exports
How the integration works
There are usually a few paths to choose from, depending on stack and budget:
- Native integration (one or both vendors offer first-party support)
- rest-api" class="glossary-link text-db-cyan hover:text-db-cyan-dark underline decoration-dotted underline-offset-2" title="Representational State Transfer - an architectural style for building web services....">REST API + scheduled sync (build once, run on cron)
- Webhook-driven sync (real-time, event-based)
- Zapier / Make / n8n (low-code, fast to ship, ongoing per-task fees)
- Custom Python / ORM, admin interface, authentication, and 'batter...">Django adapter (full control, no per-task fees, requires engineering)
What flows between the systems
Common records that move back and forth:
- primary records (customers / orders / contacts)
- events and state changes
- metadata and tags
- user actions and timestamps
Complexity
This integration is typically simple. Both tools have native or first-party support for each other, and a working integration is mostly configuration rather than custom development.
Need help building this?
Purcell Analytics builds custom integrations between Customer.io and Mailgun for businesses that want this running reliably without DIY headaches. Schedule a consultation to talk through your specific use case.