Cheat Sheet
| Question | Core Idea | Senior Signal |
|---|---|---|
| Q201 | Strict mode | Use strict checks as the baseline and migrate legacy code in controlled phases. |
| Q202 | Structural typing | Compatibility follows shape, so validate external data and brand important IDs. |
| Q203 | Inference | Let locals infer, but protect public contracts and important literal values. |
| Q204-Q205 | Unions and generics | Model valid states explicitly and use generics only when they preserve relationships. |