- Spring Boot – Stateless API Authentication with JWT
Issuing a token at login, validating it in a OncePerRequestFilter, and putting the result in the SecurityContext. Where the signing key comes from, what does and does not belong in a claim, and the honest trade-off nobody mentions: a stateless token cannot be revoked.
- iOS – Navigation
NavigationStack with a path, so a route is a value you can push, log and restore rather than a view built eagerly for a row nobody tapped. Typed routes, tabs that each keep their own stack, programmatic navigation after a payment, and where deep links plug in.
- Python – Class
Writing a class: `__init__`, what `self` actually is, instance versus class attributes, methods, and `__repr__` — the dunder that pays for itself the first time you print a list of your objects.
- Java 17 Migration Guide (11→17)
Moving from Java 11 to 17 is a much smaller job than 8 to 11. Nothing large was removed from the JDK. The one change that breaks builds is strong encapsulation — reflective access into JDK internals stopped being a warning and became an error. The change that matters Java 9 hid the JDK's internal…
- Terraform – Data Sources and Reading Existing Infrastructure
Not everything you reference is something you created. Data sources read what is already there — the latest AMI, the availability zones in this region, an existing VPC, another stack's remote state. When a data source is the right answer, when importing the resource is, and the hard-coded AMI id that stopped existing.