My coding agent stored prices as floats. 3 invoices came out a cent off.

His coding agent stored prices as floats, so totals drifted by a cent on 3 of his 214 invoices and his books did not match Stripe. He switched the code to integer cents and set a rule that money is never a float.

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How it works

Coding agent stores prices as floats
Summing line items drifts totals by a cent on 3 of 214 invoices
His books no longer match Stripe
He finds it and switches to integer cents, with a rule that money is never a float

Why it’s worth knowing

The agent code ran fine and still quietly broke his books, by one cent on 3 invoices, until Stripe did not match.

Where it’s from

Summarized from a public post on bsky.app. See the original ↗

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