Chain of custody, step by step

Record each hand-off of a sealed synthetic container, then check the chain. Everything runs in your browser; nothing is sent or saved.

SYNTHETIC DATA · Container SYN-BOX-0417 · non-tabulating · security posture: vulnerable (no independent review yet)

Seal the container

Custody log

No events yet. Choose “Record this event” to begin.

Technical details

Each record is serialised as JSON and fingerprinted with SHA-256 using the browser's Web Crypto API. Each record stores the previous record's fingerprint, forming a chain. Verification recomputes every fingerprint. A chain held entirely by one administrator could be rewritten end to end; real deployments need protected checkpoints outside any single party's control.

What this shows

A fingerprint detects when recorded bytes change after the fact.
Counts at each hand-off can be reconciled, and differences become exceptions for a person to review.

What it cannot show

A hash cannot sense touching, movement or theft of a physical container.
It does not prove the recorded facts were true when entered.
It is not an approved election system, and it holds no ballot choices or voter identities.

Next step: return to the ERC overview or try the verification walkthrough.