What factors impact integration complexity and reliability?

Integration complexity is determined by the quality and completeness of the third-party API documentation, the volume and frequency of data exchanged, the transformation logic required to align data models between systems, and whether the integration must support real-time bidirectional sync or periodic one-directional batch updates.

Reliability depends on the API provider’s uptime SLA and the robustness of the error handling implemented on the integration layer. Integrations without retry logic, dead letter queues for failed events, or monitoring alerts are fragile: a temporary API outage silently drops data that cannot be recovered. Webhooks (event-driven push notifications from the third-party system to the website) introduce additional reliability considerations since missed webhook deliveries must be reconciled through polling or replay mechanisms. Integration reliability should be treated as a first-class engineering concern, not an afterthought addressed only when failures are reported.