A company runs a website, CRM, payment service, accounting and messengers, and data flows between them constantly: leads, payments, statuses, invoices. If the links are built in a hurry, staff sooner or later start double-checking everything by hand. Integration reliability is set by the choice of exchange method — that is where every API integrations project of ours starts.
In short: webhooks give speed, API polling gives control and simplicity, queues give reliability at volume and during failures. In practice a combination works best: a webhook as the signal, an API check for details and a queue for processing with retries.
Three ways to exchange data
| Method | How it works | Pros | Cons |
|---|---|---|---|
| Webhooks | The service pushes an event to your endpoint | Instant, no extra load | Events can be lost if the receiver fails |
| API polling | Your system regularly asks for changes | Simple, you control frequency | Latency, wasted requests, API limits |
| Queues | Events are queued and processed in order | Retries, resilience to spikes and failures | Needs infrastructure and monitoring |
Principles of a reliable integration
- Idempotency. Processing the same event twice creates no duplicates — each event has a unique key.
- Retries with backoff. On a temporary error the system retries with growing intervals.
- Signature verification. Webhooks are accepted only from the genuine sender.
- Reconciliation. Periodic checks that data matches across systems catch missed events.
- Logs and alerts. Every error is visible to the team rather than discovered by a customer.
Example: payment → CRM → accounting
- The payment service sends a webhook about a successful payment.
- The receiver verifies the signature, queues the event and immediately replies "accepted".
- A worker fetches payment details via the API, updates the CRM deal and creates a document in the accounting system.
- A nightly reconciliation compares the day's payments and reports mismatches.
Frequently asked questions
Can no-code automation tools do the job?
For simple, non-critical scenarios, yes. For payments, high volumes and complex logic, your own integration layer with logs and retries is more reliable.
What if a service has no API?
Look for alternatives: file exports, email notifications, official connectors. Scraping the interface is a last, fragile resort.
How do integrations relate to analytics?
Directly: sending sales from the CRM to ad platforms improves campaign learning. See marketing analytics. The CRM usually acts as the data hub.
Need to connect services without losing data? Send a request on the API integrations page and we will map sources, data schema and failure behaviour and build integrations with documentation and monitoring.