UPS replaced its entire existing API infrastructure, deprecating access key-based authorization in favor of OAuth 2.0 security models, with post-June 3, 2024, any transaction with UPS mandating this new OAuth security model. FedEx announced on August 18, 2022 that previous FedEx Web Services WSDLs are heading for retirement, giving
Carrier webhooks fail at rates that would bankrupt a traditional SaaS platform. The business costs of webhook failures can be substantial, including lost sales, customer dissatisfaction, regulatory penalties, and operational disruption costs, and in carrier integrations, these failures happen far more frequently than other domains. The numbers tell a harsh
Your carrier API monitoring setup decides whether you catch integration failures before your customers do. Over the past over 4 years, we have collected data on on more than 332 outages that affected ShipEngine API users. You're left unable to calculate shipping rates and customers aren't
Your observability budget just tripled. Again. Those innocent-looking auto-instrumentation settings you rolled out six months ago are now generating data volumes 4-5x higher than expected, creating unsustainable costs for your carrier integration middleware. Sound familiar? If you're architecting or operating carrier integration software that handles multi-carrier API routing,
Carrier APIs change without warning. You know this if you've ever woken up to broken rate requests or mysteriously failed label generation. Integration bugs discovered in production cost organizations an average of $8.2 million annually, while contract testing catches these issues early, reducing debugging time by up
Static rate limits are failing everywhere. Financial services, telecoms, and travel sectors faced 40,000 API incidents in the first half of 2025, with attacks projected to hit 80,000+ by year end. The API management market reached $6.89 billion in 2025, yet most middleware still relies on fixed
Major carriers are actively migrating away from SOAP-based APIs, with FedEx retiring their legacy Web Services in May 2024 and moving to RESTful APIs, while UPS transitioned from XML protocols to OAuth 2.0-secured REST endpoints. AsyncAPI has emerged as the industry standard for defining asynchronous APIs, creating a unique
When your multi-carrier platform reaches serious scale, traditional single-node rate limiting starts to break down. You can't just multiply limits by server count and hope requests distribute evenly. One busy integration server gets all the DHL traffic while another sits idle handling UPS requests. Your rate limits become
Carrier integration middleware for multi-tenancy needs more than shared database patterns and token-based routing. When tenant service APIs become overloaded, they impact other APIs and dashboards because Tenant Service is part of API request authorization logic, as Cloudflare discovered during their September 2025 outage. If tenant isolation is not properly
Every shipping systems architect has faced this conundrum: your carrier integration platform needs real-time webhook delivery, but your stakeholders insist that tracking updates must arrive "in order". You know intuitively that shipment events follow a natural sequence—label created, picked up, in transit, delivered—so ordering seems obvious.
When FedEx's API went down at 2 AM and took out shipping for 40% of your tenants, you learned something important about circuit breakers. Traditional circuit breaker patterns don't handle multi-tenant carrier integration gracefully—when one carrier fails, the blast radius shouldn't encompass every
Your carrier experiences an outage. You're left unable to calculate shipping rates and customers aren't impressed. Label generation duplicates when your retry logic fires twice. Rate shopping fails when your cache logic stores partial responses. Welcome to the carrier integration reliability challenge. Standard idempotency patterns weren&