bINT ledger (normative)

5.7 bINT ledger (normative)

The off-chain mirror of bINT credits. Append-only.

json

// BintLedgerEntry
{
  "ledger_entry_id": "01HXY...",
  "user_id": "01HXY...",
  "wallet_address": "5Hg2...8fpA",
  "source": "receipt",
  "source_id": "01HXY8K3F9A2QZ0M1B7N4PQR5W",
  "amount_minor": 12500,
  "currency_code": "bINT",
  "trust_score_at_credit": "0.XX",
  "level_at_credit": "<L>",
  "health_at_credit": "0.XX",
  "daily_cap_band": "<band>",
  "created_at": "2026-05-17T14:23:12Z",
  "settled_to_chain_at": null,
  "onchain_tx_signature": null,
  "previous_entry_hash": "sha256:9a01...",
  "entry_hash": "sha256:b3f8..."
}

Why a cryptographic chain

previous_entry_hash + entry_hash form a hash chain over the ledger. This gives Yumo Yumo a verifiable audit log: even though the ledger is operationally a Postgres table, the hash chain means a tampering attempt is detectable. The latest entry_hash is published on-chain periodically (a Merkle root commitment) so external parties can verify ledger integrity.

Settlement

The settlement worker batches BintLedgerEntry rows with settled_to_chain_at IS NULL and mints the aggregated bINT on Solana. After confirmation, settled_to_chain_at and onchain_tx_signature are populated. From that point on the on-chain state is the source of truth for that entry.