API & Webhooks

A high-level overview of how you connect LeadStack to the rest of your stack.

LeadStack ships a REST API and signed webhooks so your workspace can talk to the tools you already use — sync contacts and deals, drive your own automations, and react to what happens in real time.

1. REST API

Versioned REST endpoints under /api/v1/ give you read/write access to your core records: contacts, deals, tasks, calendar events, and form submissions.

Requests authenticate with a workspace API key sent as a Bearer token. Each workspace mints its own keys in separate live and test modes, so you can build and verify against test data before switching anything on in production.

It’s built for real integrations, not just demos: idempotency keys make writes safe to retry, a versioned response envelope keeps your integration from breaking when we ship improvements, and every key has its own rate limit.

2. Webhooks

Subscribe an endpoint to the events you care about and LeadStack POSTs to it the moment they happen — no polling, no cron jobs on your side.

Every payload is signed with HMAC-SHA256 and carries Webhook-Signature and Webhook-Timestamp headers, so you can verify each request genuinely came from LeadStack and reject anything stale or replayed. Failed deliveries are retried automatically.

Events you can subscribe to include:

• contact.created — a new contact enters the workspace
• form.submission.created — a hosted form is submitted
• Deal stage changes — a deal moves along your pipeline
• event.booked — someone books through a booking page
• message.received — an inbound SMS, WhatsApp, or social DM lands
• call.missed — a call goes unanswered

3. Keys & security

API keys are scoped to a single workspace — a key only ever sees that workspace’s data. Secrets are shown once at creation and stored hashed, so treat them like passwords. You can revoke and rotate keys at any time without disrupting the rest of your setup.

4. Getting connected

Ready-made recipes for Zapier, Make, n8n, and plain cURL are built in, so the most common integrations are copy-paste rather than a project.

5. Requesting new endpoints or events

The API and webhook catalog keeps growing. If you need an endpoint or an event that isn’t listed yet, request it via the Feature Request link in the footer — it’s the fastest way to get it onto the roadmap and to see what others have already asked for.

6. Questions

Have a question about the API or webhooks before you build? Ask us via Chat — we’re happy to walk you through it.