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CASE STUDY / 08

Reconciling the numbers before release.

I found divergent invoice calculations, implemented a canonical correction, added regression coverage, and confirmed ambiguous accounting policy with stakeholders.

Production delivery

Rails · confidential client

Outcome Released correction with no known related recurrence or complaint.

The problem

Generated invoices and account-balance behavior needed reconciliation against real data. Duplicate calculation paths produced inconsistent totals.

My decision & contribution

I organized fixes by risk, corrected a CHF 1,778 discrepancy, and made affected views consume the same source of truth. Business-policy ambiguity was resolved with the appropriate stakeholder before implementation.

The result

The correction and regression coverage shipped. No related recurrence, reconciliation issue, or stakeholder complaint was known afterward; a quantified support reduction is unavailable.

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