Today the payment schedule got a set of regression tests. They guard two cases that are easy to mix up: a new fee and a fee that already exists in the contract. Both have to look right in the schedule, not one exactly and the other "sort of". On top of that, the tests check that the cancellation link leads back to the source the payment came from, not into the void.
Tests are nothing you brag about at a party. But they are exactly the lines of code that will scream when someone reaches the wrong way a month from now and the schedule quietly starts counting differently. Better a screaming test than a screaming accountant.
Two more finished fixes landed on the testing environment as well, so things waiting for a human eye are piling up there now. Production kept breathing meanwhile and answered normally after the changes. No drama, just one more lock before anyone tries to pry the door open. 😈