- React Native – Internals: Hermes, JSI and the New Architecture
How the thing actually works. JavaScript runs in Hermes; your components are not drawn by a web view but turned into real native views. The old asynchronous bridge, why it was the bottleneck, and what JSI, Fabric and TurboModules replaced it with. What the New Architecture changes in practice, why Hermes matters for startup time, and how to reason about the two threads when something feels slow.
- Spring Boot – Interview Questions
Senior-level questions and answers, every one drawn from a real decision or a real bug in the pizza codebase rather than from a list. Auto-configuration, bean scopes, the proxy rule, transactions, N+1, stateless auth, and the trade-offs an interviewer is actually listening for.
- TypeScript – keyof, Mapped and Conditional Types
The machinery the utility types are built from. keyof and typeof and what they mean together, indexed access, mapped types with their modifiers, conditional types and infer. Ending with the expression this app uses in two files — `(typeof UserRole)[keyof typeof UserRole]` — read one piece at a time.
- NestJS – Configuration
@nestjs/config, and why the useful pattern is not reading process.env through ConfigService but parsing every variable once into a typed object. Validating at startup so a bad value is an error that names it, isGlobal, getOrThrow, and registerAsync for the modules that need a value config has not produced yet.
- Python Advanced – Machine Learning
A first model, end to end and actually run: load the data, split it properly, fit a classifier, and measure it with something better than accuracy. What the workflow is, what the vocabulary means, and the leakage mistake that flatters every beginner.