Every floor · The machinery
Builds and runs the systems the bank's money, records and customers move through.
BY MICHAEL SHANG · SIXTEEN YEARS IN COMMERCIAL BANKING · UPDATED
The engineering is engineering — but the systems are ledgers, payment rails, limit checks and customer channels, where a duplicated message is a duplicated payment and an outage is somebody's payroll. Correctness, idempotency, reconciliation and an audit trail carry weight here that they do not carry everywhere.
Hired on the discipline rather than on banking: computer science graduates, bootcamp leavers and experienced engineers from other industries.
These are the shapes the round takes, not a question bank — banks phrase them differently and the wording is never the point.
What the panel is listening for. Correctness before cleverness, and whether you can name who is hurt when your component fails.
Practise the round in the finance, technology and operations quiz: one of its five questions is this seat's own, and every answer has the senior interviewer's read.
Take the quiz →A strong answer makes the change reversible before making it clever: behind a switch, to a small slice first, with the old path running beside the new so the two can be compared on real traffic. It says what is watched before the slice widens — reconciliations that still balance, no rise in exceptions — and who can turn it off at three in the morning without a meeting. And it names the one kind of change that cannot be staged, a migration of the data itself, and rehearses that on a copy first.
A weak one trusts the test suite and a careful review, then ships to everyone at once, which is how a change that passed every test meets the one case nobody wrote down.
Correctness before cleverness is the whole test, and the follow-up is always who is hurt when your component fails. Nobody expects an engineer to read a balance sheet, but the bank's engineers know what the ledger is for; the ones who move into risk, data and platform leadership tend to be the ones who learned what the lending systems carry, and How Banks Work is the shortest route to that.
START HERE · How banks work
THE IN-TRAY · ONE MINUTE
A short file on the ground this page covers. Every option opens with how far it sits from a senior banker’s read.
Two US$3m requests land the same morning. One borrower's cash flow covers the debt comfortably, but the only security is stock. The other offers a first mortgage over land worth twice the loan, with cash flow that barely covers the interest.
1 FILES · PICK A CALL ON ANY OF THEM
5 MORE ON CHAPTER 1 · THE THREE QUESTIONS →WHERE DO YOU READ FROM? THE PLACEMENT →
The whole board, and how the four blocks fit together, is on what jobs banks hire for.
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