A QR code that grants nothing
Candidates pay at a counter, not online. The QR code that joins the two carries no authority — and the guard lives in one function, not four screens.
One seat, one candidate
Sixty-three exams, zero convocations. A seat is a physical resource that can be taken twice. The constraint, the race, and the report that names refusals.
Documentation that shows the holes
A workflow that lives in data has no readable form. A hand-drawn diagram is wrong in a month. Generate it — and make it report what has no path.
An import that tells you what it will do
A school's data arrives as spreadsheets nobody cleaned. The hard part is not parsing them: it is saying what will happen before it happens.
One hundred and sixty characters, none of them accented
One non-GSM character drops the limit from 160 to 70. Transliteration, a measured budget, and knowing what must never be truncated.
The third verdict — rules that check without deciding
Two verdicts force a system to call missing data a failure. The third one — to be checked — is what separates a decision aid from an automatic rejection.
A foreign key we deliberately did not create
Referencing by code instead of by FK buys real decoupling and costs a guarantee. An incident, its two faults, and why the second one was worse.