09 · Company operations · Sep 2026
Financial OS
The company's books as one ledger that reconciles exactly to the bank, with a P&L per client built on top.
What I built
- A statement parser and a single transaction ledger: 561 transactions across 4 bank accounts, reconciled to the cent.[58] SourceRevolut statement parse, Financial OSAs of2026-09-14StatusVerifiedAll sources →
- A P&L per client and a software register, all formulas over the one ledger, with a backtest that recalculates the workbook offline.
What was hard
Money that nobody had attributed
Costs had been split evenly across clients for months. The ledger now shows untagged rows as a gap instead of hiding them in an average.
What I learned
- A gap you can see is better than an average that hides it.
Results
- One source of truth for every client's margin.