Monitor your carriers and logistics providers APIs.
Package tracking and label generation depend on carrier APIs. An outage can block your shipments and frustrate your customers.
Monitor your carrier APIs to anticipate logistics problems.
Some do (UPS, FedEx), but not all. External monitoring is more reliable.
Implement a fallback to an alternative carrier if possible.
Monitor at least your main carriers and those without fallback.
Use test environments provided by carriers.
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