ShipMargin
Rule intelligence

Carrier rules with provenance

A carrier formula cannot reach a production calculator until its source, effective date, version, and verification status pass review.

Immutable versions

New rules create new versions; historical rules are not overwritten.

Verified-only runtime

Unverified rules stay visible for review but cannot power final carrier results.

Effective dates

Calculations resolve the rule that is effective for the applicable date and country.

usps

verified

USPS Priority Mail dimensional weight · Effective 2026-07-12

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ups

unverified

UPS dimensional-weight rule · Effective 2026-01-01

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fedex

unverified

FedEx dimensional-weight rule · Effective 2026-01-01

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