Why a Developer-First API Matters
Most email platforms treat developers as an afterthought. Their APIs are clunky, documentation is sparse, and you spend hours figuring out basic functionality.
Sequenzy was built by developers, for developers. Every API endpoint was designed with DX in mind:
- Intuitive endpoints — Resource-based URLs that make sense
- Type-safe SDK — Full TypeScript support with autocomplete
- Helpful errors — Clear messages that tell you what went wrong
- Real documentation — Interactive examples, not just reference pages
Unified Transactional + Marketing
Stop juggling multiple email providers. With Sequenzy, one API handles:
Transactional emails — Password resets, order confirmations, notifications Marketing automation — Trigger sequences based on user events Subscriber management — Tags, attributes, list membership Analytics — Opens, clicks, conversions, revenue attribution
All in one integration. One set of templates. One dashboard.
| API job | Endpoint pattern | Product outcome |
|---|---|---|
| Send transactional email | Send template with variables | Reliable user notifications |
| Trigger custom event | Record event with properties | Behavior-based automation |
| Upsert subscriber | Sync user attributes | Accurate segmentation |
| Apply tag | Mark lifecycle status | Trigger tag-based flows |
| Receive webhook | Process delivery event | Keep internal systems synced |
Built for Production Scale
The API is designed for real-world usage:
- A fast transactional send path for emails like password resets
- Generous rate limits that won't block you
- Idempotent requests to prevent duplicates
- Retry-safe webhooks with exponential backoff
- 99.9% uptime SLA on Enterprise
| Production concern | API feature | Why developers care |
|---|---|---|
| Duplicate sends | Idempotent requests | Safe retries |
| Debugging failures | Typed errors and logs | Faster incident resolution |
| High-volume events | Generous rate limits | Fewer queue bottlenecks |
| Real-time sync | Webhooks | Accurate downstream state |
| Type safety | TypeScript SDK | Catch mistakes before deploy |
Webhooks for Real-Time Sync
Keep your systems in sync with webhook events:
// Your webhook endpoint receives signed events like:
{
"id": "evt_123",
"type": "email.sent",
"object": "event",
"metric": "sent",
"created_at": "2026-05-05T12:00:00.000Z",
"data": {
"email_send_id": "send_123",
"subscriber_id": "sub_123",
"external_id": "customer_123",
"recipient": "user@example.com",
"subject": "Welcome",
"email_type": "campaign"
}
}
Use webhooks to update your CRM, trigger follow-up actions, or sync analytics.