01
Balance drift
Stored balances that don't match transaction history because of race conditions and destructive updates.
Balance mismatches, race conditions and audit gaps in a financial ledger
Double-entry ledger and event sourcing architecture
Build an append-only, double-entry ledger with idempotent writes and ordered events, so every balance can be explained and rebuilt from its history.
Symptoms
Signs your platform has this problem
If several of these sound familiar, the plan below is where we would start.
02
Audit gaps
No way to reconstruct an account's balance on a past date for auditors or regulators.
03
Duplicate charges on retries
No idempotency keys, so a retried request charges the customer twice.
Remediation plan
How we fix it, step by step
Each phase ends with a measurement, so you can see what changed before the next one starts.
01
Double-entry schema
Append-only ledger entries where debits equal credits for every journal entry.
02
Idempotency and locking
Unique idempotency keys, with PostgreSQL row-level locks on balance updates.
03
Event sourcing on Kafka
Publishing ordered transaction events to account-partitioned Kafka topics.
04
Balance projections
Materializing current balances into Redis for fast reads in the customer UI.
Technical checklist
Remediation checklist
What we check before a change goes to production:
- Remove destructive UPDATE and DELETE statements on financial transaction tables
- Enforce debit-equals-credit constraints in SQL
- Add UNIQUE idempotency key constraints on payment requests
- Serve dashboard balances from projections, rebuilt from the ledger
What we measure
We take a baseline first and report the same measurements after each change, from your own monitoring — evidence, not promised results.
- Reconciliation
- Accounts whose balance matches the sum of entries, checked nightly
- Duplicates
- Duplicate requests caught by idempotency keys
- Commit latency
- Transaction commit time at p95
Related service
Custom software
Custom software for Indian SMEs and startups, built around your workflow with an agreed scope, review milestones, clear ownership and documented handover.
Explore Custom softwareQuestions
Questions about this remediation
Event sourcing keeps the complete history of every money movement, so you can reconstruct any account's state at any point in time for an audit.
Because the ledger is append-only, errors are corrected by posting a new compensating journal entry rather than editing history.
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Want an engineer to look at this with you?
Send us the symptoms and any metrics you have. We'll reply within one business day, set up a call and agree what to measure before anything changes.