APIs are the connective tissue of modern software. Whether you're integrating a payment gateway, a CRM, or a logistics provider, the patterns for doing it well are consistent.
Authentication Patterns
Most modern APIs use OAuth 2.0 or API keys. For server-to-server integrations, use API keys stored in environment variables - never hardcoded. For user-facing integrations, OAuth 2.0 with proper token refresh handling is the standard.
Error Handling
APIs fail. Networks are unreliable. Build your integration to handle failures gracefully. Implement exponential backoff for retries, circuit breakers to prevent cascade failures, and dead letter queues for messages that cannot be processed.
Rate Limiting
Every API has rate limits. Respect them. Implement a token bucket or sliding window algorithm on your side to stay within limits. Cache API responses aggressively.
Webhooks vs Polling
Webhooks are almost always better than polling. Instead of asking "did anything change?" every 30 seconds, webhooks let the API tell you when something changes. Always validate webhook signatures to prevent spoofing.
Conclusion
A well-built API integration is invisible - it just works. Invest the time upfront to do it properly and you will save yourself significant pain down the road.
