Contact management and audiences
Import contacts, build audiences, and segment recipients for targeted email. Subscription topics and RFC 8058 one-click unsubscribe are handled for you.
Audience management
Group contacts into audiences. Import from CSV, sync from your app over the API, and export at any time. No lock-in, no per-contact fees.
Segmentation that actually ships
Filter by tags, custom fields, and engagement signals. Save segments, send broadcasts to them, and watch them update as contact data changes.
Compliant unsubscribe handling
Subscription topics let contacts opt out of one stream without losing others. RFC 8058 one-click unsubscribe is added to every marketing send for Gmail and Yahoo compliance.
Create a contact
typescript
await poststack.contacts.create({
email: 'alice@example.com',
firstName: 'Alice',
lastName: 'Smith',
tags: ['customer', 'pro-plan'],
customFields: {
company: 'Acme Inc',
signedUpAt: '2026-01-15',
},
});