Guides double-entry ledger design: journal entries, chart of accounts, sub-ledgers (AR, AP, GL), reconciliation between ledgers, immutable append-only audit trails, balance calculations (running vs computed), and ledger-as-event-log pattern. Use when designing accounting systems or financial record-keeping.
Guides double-entry ledger design: journal entries, chart of accounts, sub-ledgers (AR, AP, GL), reconciliation between ledgers, immutable append-only audit trails, balance calculations (running vs computed), and ledger-as-event-log pattern. Use when designing accounting systems or financial record-keeping.
Ledger Design
When to use
Designing a double-entry bookkeeping system from scratch
Choosing a chart of accounts numbering convention
Building AR, AP, or GL sub-ledgers with reconciliation
Implementing immutable audit trails with reversal patterns
Deciding between running balance vs computed balance strategies
Applying event sourcing to financial record-keeping
Core principles
Debits always equal credits — enforce with DB constraint; reject unbalanced entries at the boundary
Never UPDATE or DELETE journal entries — corrections via reversing entries only; history is sacred
Running balance is a cache — journal lines are the source of truth; reconcile daily
Hash chain for tamper detection — SHA-256 chained hashes make unauthorized edits detectable
Sub-ledger detail must reconcile to GL control account — any gap is a critical alert, not a warning
Reference Files
references/double-entry-journal.md — golden rule, debit/credit rules table, example entries, journal_entries and journal_lines SQL schema, entry validation rules
