Webhook Retry Queue Architecture for the 2026 Carrier Migration Wave: Multi-Tenant Patterns That Survive API Reliability Crises
The major carrier API migrations completing in 2026 reveal a harsh truth: USPS Web Tools APIs shut down January 25, 2026, while FedEx's remaining SOAP-based endpoints will be fully retired in June 2026. Yet beneath these well-documented migrations lies a deeper problem threatening webhook retry queue architectures. Traditional