Incident 14 September
Status: resolved · Severity: 2 · Lead: Kenji Mori
Invoices generated between 09:12 and 09:51 rounded VAT down instead of to the nearest cent.
Timeline
| Time | What happened |
|---|---|
| 09:12 | Deploy of the new tax engine |
| 09:40 | Support flags three tickets about totals off by one cent |
| 09:51 | Change reverted, see Deploy guide |
| 11:30 | Affected invoices reissued |
What we're changing
- Property-based tests for every rounding mode
- Tax engine changes ship behind Feature flags
- Alert when support tickets mention "invoice" more than five times an hour
Nobody did anything wrong here. The test suite only checked whole-number amounts.