- Spring Boot – Messaging with JMS
Handing work to a queue so the request can return. JmsTemplate, @JmsListener, converting a message payload to JSON, and what to do with a message that keeps failing — because without a dead-letter destination it is redelivered forever.
- Python Advanced – functools, operator, and reduce
The functional toolkit that survives the comprehension argument: reduce where it is genuinely the right shape, partial for pre-filling arguments, cache and singledispatch, and the operator module that replaces most small lambdas.
- Python – User Input
`input()` always hands you a string, which is where most beginner bugs start. Validating and converting it, looping until the answer is usable, hidden input for passwords, and `argparse` when the input is command-line arguments instead.
- Frontend Dev – The JavaScript and TypeScript You Actually Need
The subset of the language that matters in a component app, which is not the subset a beginner course teaches. Immutable updates, the async model that makes a spinner possible, modules, and the handful of TypeScript ideas that catch real bugs — typing the API response, discriminated unions for loading state, and why `any` is a loss.
- Java 25 Flexible Constructor Bodies
Until Java 25, super() or this() had to be the very first statement in a constructor. Nothing could run before it. Flexible constructor bodies lift that restriction, which means you can finally validate an argument before handing it to the superclass. The restriction That rule existed for a good…