The claim being made
TrackJet claims that no shipment history is silently rewritten — not even by TrackJet. That claim is mechanically checkable. This page is the auditor's path.
Layer 1: per-shipment hash chain (tjvt1)
Each tracked chain's events are sealed at ingest: h(n) = SHA256(h(n-1) ‖ canonical(event_n)), with a genesis derived from the shipment's identity. The public proof endpoint returns the seal list:
`` curl https://trackjet.world/api/v1/shipments/<uuid>/proof ``
Verifiable offline: genesis recomputation (from the tracking number you already hold), link continuity, head consistency.
Layer 2: public Merkle log (tjmt1)
All sealed heads anchor into an append-only Merkle tree; roots are published:
`` curl https://trackjet.world/api/v1/transparency/roots # root history curl https://trackjet.world/api/v1/shipments/<uuid>/inclusion # audit path ``
If any past timeline were rewritten, its head would change, the old inclusion proof would stop folding to the published root, and any holder of the old proof can demonstrate the rewrite.
The tool
tjverify is a single-file, dependency-free, open-source CLI:
`` tjverify chain proof.json --tracking <number> tjverify inclusion inclusion.json --root <pinned-root-hex> ``
Exit code 0 = valid, 1 = invalid. Pin a root you fetched yourself for a fully independent check.
Audit procedure (suggested)
1. Pick shipments at random; fetch proofs + inclusion proofs; verify offline. 2. Pin today's root; re-verify the same proofs next quarter against your pinned root. 3. The specs (tjvt1, tjmt1) are published under [/standards](/standards) — implement your own verifier if you prefer not to run ours.