Problem
Month-end close ran on a spreadsheet that had grown for years past anyone's ability to reason about it. Reconciliation took the finance team the better part of a week, every formula change risked silently breaking another, and no one could say with confidence that the numbers were right — only that they usually were.
Approach
We rebuilt the reconciliation as a typed pipeline: each source system maps into a single validated schema, mismatches surface as explicit exceptions rather than quiet drift, and every run is reproducible. On top of it we put a small review UI so the team could approve, annotate, and override line items without ever touching a formula.
- Validation at the boundary — bad inputs fail loudly, not at quarter-end.
- A full audit trail: who changed what, when, and why.
- The whole thing runs in minutes and can be re-run on demand.
Result
The close went from days to minutes, the bulk of manual review disappeared, and the team trusts the output enough to act on it the moment it lands.