Directory

The definitive reference for HTTP methods, status codes, and semantics.

Standard format for machine-readable error responses.

Official SOAP 1.2 specification for understanding envelope, header, and fault structure.

Web Services Description Language specification for reading carrier service contracts.

API development and testing platform. Essential for exploring carrier APIs manually.

Dedicated SOAP and REST testing tool. Import WSDLs to auto-generate test requests.

Network protocol analyzer for inspecting raw HTTP/SOAP traffic during debugging.

HTTP request/response testing service. Great for testing retry logic and error handling.

FedEx REST and SOAP API documentation, sandbox, and integration guides.

UPS API documentation including SOAP and REST endpoints for shipping and tracking.

DHL Express, eCommerce, and Parcel API documentation and sandbox.

USPS XML-based APIs for address validation, shipping, and tracking.

Foundational article on the circuit breaker resilience pattern.

Deep dive into retry strategies with exponential backoff and jitter algorithms.

Best-in-class example of idempotency key implementation in a production API.