How finzu repairs order

A lot of “the numbers don’t add up” turns out to be transactions landing in the wrong order — two purchases on the same day imported in reverse, say. Nothing about the transactions themselves is wrong; they’re just out of sequence. Finzu can fix that on its own.

Take that earlier Chain Break example:

Date	Description	Amount	Reported Balance
Jan 5	Paycheck	+$2,000	$2,495
Jan 8	Rent	−$1,800	$695

Finzu tries different orderings of nearby transactions and checks which one makes the whole chain reconcile. If moving Paycheck a day later resolves the break and nothing else about the chain regresses, finzu applies that reorder — it changes where a transaction sits, never its date, amount, or balance.

The safety net

Reordering is only worth doing if it actually helps. Before finzu keeps a reorder, it re-checks the whole account: did Chain Breaks and Balance Drift both get better, or did fixing one spot just move the problem somewhere else? If a repair would leave the ledger worse off by either measure, finzu throws it away and leaves the account as it was — flagged, but honestly flagged, rather than “fixed” in a way that hides a different problem.

What it can’t fix

Reordering only helps when the real transactions are all there, just misfiled. A genuinely missing or duplicated transaction — the kind that causes Balance Drift — isn’t something reordering can repair, because there’s no ordering of the existing rows that makes the math come out right. That needs a human to find the missing piece.

Next: pinning down where an account’s history truly begins.