An API-first platform lets a store, CRM, support tool, or custom application manage contacts, campaigns, and automations without opening the dashboard. Production integration, however, is more than a successful HTTP request. Secret storage, tenant scope, validation, idempotency, bounded retries, and signed webhook verification belong in the same design. Use the Bartago Swagger contract for request and response shapes, and keep a stable external reference so a retry cannot create a duplicate campaign or message.
Keep a server-to-server boundary
Do not ship API keys in a browser or mobile bundle
Store secrets only in a trusted backend or secret manager. Use least-privilege keys, separate environments, and a rotation date. Mask authorization headers, provider secrets, and contact PII in logs.
Design idempotent requests
A timeout does not prove failure
The server may complete an operation after the client times out. Retry with a stable order, lead, or campaign reference and return the existing result. Use exponential backoff and a maximum attempt count for network errors.
- HTTPS
- Scoped API key
- Stable idempotency ID
- Timeout and bounded retry
- Structured error handling
Verify webhooks and acknowledge quickly
Authenticate first; process asynchronously
Verify the raw payload and provider signature, deduplicate the event ID, return 2xx quickly, and place business work on a durable queue. Design for out-of-order events. Reject a mismatched secret or stale signed timestamp.
Practical checklist
- Swagger contract
- Backend-only key
- Idempotency reference
- Retry ceiling
- Webhook signature
- Replay test
Key takeaway
A reliable integration is a contract for duplicates, timeouts, replays, and out-of-order events—not only the happy path.
Final thoughts
In a test workspace, create one contact, enqueue one message, and replay one webhook. Confirm logs contain no secret and the same request or event still creates only one business action before issuing a production key.
Verify consent, provider or carrier policy, and current applicable requirements before launching a campaign.
Start with 100 free automation credits →Common questions
Should an API key be stored in the Flutter app?
No. Keep a long-lived workspace key on a backend and use a scoped, short-lived mechanism for app pairing or sessions.
What if a webhook arrives twice?
Provider retries are normal. A stable event ID and idempotent handler prevent duplicate business actions.
Sources and editorial note
Last editorial review: August 1, 2026. Product behavior may change with releases; check current documentation.