Immutable loan ledgers explained
Trustworthy recovery starts with a balance nobody can quietly change.
Updated 2026-10-20
What it is
An append-only ledger never updates or deletes entries. Each charge, payment and correction is a new, dated, attributed row.
Design rules
- Store money as integers in minor units.
- Derive balances by summing entries; never store an editable balance.
- Use unique idempotency keys so retries and concurrent requests cannot double-post.
- Correct mistakes with reversals that reference the original.
- Enforce immutability in the database as well as the application.
Benefits
Disputes are easier to resolve, audits are faster, and reconciliation differences become visible rather than hidden.