Feature / REST API
One API call. Segments update everywhere.
Push an event from your app, watch segments and workflows react. Clean REST API with simple API-key auth, documented in the kind of prose you actually want to read.
- API-key auth per workspace
- CRUD on contacts + attribute updates
- Event ingestion for behavioral triggers
- Webhooks for outbound events (open, click, bounce, unsubscribe)
- Bulk endpoints for batch imports / syncs
How it works
A closer look at what makes it tick.
One endpoint for the 90% case
POST /api/v2/contacts is idempotent on the email field, send the same payload twice and you update the same contact. Send it with new attributes, the contact's segments re-evaluate in real time. This is the entire integration for most SaaS: call this endpoint whenever your backend state changes.
Events for behavior
If you want to trigger workflows from product events (user_upgraded, feature_X_used) without mutating attributes, POST /v1/events. Events can carry structured data and can target workflows directly.
Webhooks back to your app
Subscribe to outbound events: email opened, clicked, bounced, marked as spam, unsubscribed. Use these to update your own analytics, CRM, or product state. HMAC-signed for verification.
Example use cases
Who this is actually for.
User signup
Create contact with email, plan, signup_date. Trigger onboarding workflow.
Plan upgrade
Update plan attribute. User exits Free segment, enters Pro segment, relevant workflows fire.
Feature activation
POST /v1/events with feature_name. Triggers feature-specific nurture.
Account deletion
DELETE /api/v2/contacts/{id}. GDPR-clean, contact removed from all segments.
await fetch('https://api.segmailer.com/api/v2/contacts', {
method: 'POST',
headers: { 'Authorization': `Bearer ${API_KEY}` },
body: JSON.stringify({
identifier: {
email: 'user@example.com'
},
attributes: {
firstName: 'Jane',
lastName: 'Doe',
plan: 'premium',
signupDate: '2024-01-15'
}
})
})
// → segments re-evaluate within 1s
// → active workflows targeting this contact reconcileFAQ
REST API, answered.
Plain HTTP is the primary interface, you don't need an SDK. We also publish a minimal TypeScript client for convenience. Any language that can make an HTTPS request works.
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