Webhook Signature Schemes Across 10 Shipping APIs

We checked webhook signature methods on 10 shipping/carrier platforms as of October 2026: algorithms, headers, replay windows, and what's undocumented.

Circuit Breakers in Carrier Integration, Explained

What the circuit breaker pattern is, how it differs from retries, and how carrier integration platforms apply it per carrier.

Migrating From GLS UniBox To The REST API

A step-by-step guide to migrating from GLS UniBox to the GLS ShipIT REST API, covering credentials, createParcels, idempotency and ConfirmLabel.

Batch Shipment Limits Across 9 Carrier APIs

Batch and bulk-request limits for FedEx, UPS, DHL, USPS, Shippo, EasyPost, Sendcloud and more — sourced from current docs, dated October 2026.

Dead Letter Queue vs Retry Queue: The Real Difference

Dead letter queue explained for carrier integration: how it differs from a retry queue, with a worked webhook example and FAQ.

Migrating to PostNL Shipment API v4, Step by Step

How to move a production PostNL integration to Shipment API v4: field mapping, barcode-to-reference tracking, key rotation, and rollback steps.

Carrier Integration Software Uptime: 12 SLAs Compared

Published uptime SLAs, marketing claims, and measured data for 12 carrier integration and shipping API platforms, as of September 2026.

The Transactional Outbox Pattern, Explained

How the transactional outbox pattern stops shipment records and carrier webhooks drifting out of sync, with a worked booking example.

Migrating UPS API from XML to OAuth 2.0 REST

A step-by-step guide to migrating multi-tenant UPS integrations from XML/Access Key to OAuth 2.0 REST, with token-caching to avoid rate limits.

Multi-Carrier Shipping Software Pricing: 9 Vendors

Per-label fees, subscription tiers, and free-plan limits across nine multi-carrier shipping platforms, sourced from vendor pricing pages, September 2026.

Rate Shopping, Explained

What rate shopping means in carrier integration software, how fan-out vs cached rate engines differ, and how to budget timeouts across carriers.

Generating SSCC-18 Labels in a Multi-Tenant Platform

Learn to generate GS1-128 SSCC-18 pallet labels in a multi-tenant carrier platform: AI structure, Mod-10 checks, ZPL output, and tenant-safe serials.

carrier count comparison

Carrier Count Claims: What 9 Vendors Publish

We checked carrier-count claims on 9 multi-carrier platforms' own pages. See the table, the contradictions, and what to verify before you build.

transportation spend management

Transportation Spend Management, Explained

What transportation spend management is, how it differs from freight audit and a TMS, and the data pipeline that makes it trustworthy.

FedEx REST API migration

FedEx SOAP to REST API Migration, Step by Step

A step-by-step FedEx REST API migration guide: OAuth2 setup, field mapping, idempotent cutover, and dual-run verification for multi-tenant middleware.

webhook timeout

Webhook Timeout Windows: 7 Platforms Measured

Published webhook ack timeouts, retry counts and uptime SLAs from 7 carrier/shipping platforms, with sources and the date each figure was collected.

bulkhead pattern

What Is the Bulkhead Pattern in Carrier Middleware?

The bulkhead pattern isolates each carrier connection into its own resource pool. Definition, worked example, and how it differs from a circuit breaker.

DHL Parcel DE Shipping API migration

DHL Paket API Migration: SOAP v3 to REST V2

A step-by-step runbook for migrating DHL Parcel DE Shipping integrations from retired SOAP v3 to REST V2, with OAuth2 setup and field mapping.

carrier API token expiry

Carrier API Token TTLs: 14 Vendors Measured

Access and refresh token lifetimes for 14 carrier and multi-carrier APIs, sourced from vendor docs, with token-cache design guidance.

carrier integration software

Carrier Integration Software vs TMS, Explained

What carrier integration software actually is, how it differs from a TMS in architecture, and a worked example with real vendor names.

carrier webhook dead-letter queue

Carrier Webhook DLQ Redrive Without Duplicate Shipments

A step-by-step guide to redriving an AWS SQS dead-letter queue of carrier webhooks without creating duplicate shipments.

carrier webhook retry policy

Carrier Webhook Retry Windows, By The Numbers

Published retry counts, backoff windows, and OAuth token TTLs for FedEx, DHL, Shippo, AfterShip and more, sourced and dated as of August 2026.

carrier integration software

Carrier Integration Software: What It Actually Is

Carrier integration software, defined and distinguished from TMS, TES and multi-carrier shipping software, with a worked example of where each layer sits.

EDIFACT IFTMIN

How to Send a DB Schenker Transport Order via EDIFACT

Step-by-step guide to building an EDIFACT IFTMIN transport order for DB Schenker, sending it via AS2, and parsing IFTMCS/IFTSTA replies.