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interview

7 articles

·6 min read

Spring Boot Interview Questions for Experienced Developers, Settled by Running Them

Seven Spring Boot questions senior interviews ask, answered with real output — starting with the @Transactional method that threw and still committed.

Backend & APIs
·7 min read

Java 8 Stream API Interview Questions, With the Output to Prove It

Java 8 stream interview questions answered with output from JDK 8, 21 and 25, including a sorted() that did no work and a parallel reduce wrong every time.

Java
·7 min read

Git Interview Questions and Answers, Proved in a Terminal

Ten git interview questions answered with terminal output on git 2.50.1, from what a commit holds to why following git's own push hint undid a fix.

Cloud & DevOps
·9 min read

Microservices Interview Questions, Answered by Running Them

Seven microservices interview questions answered with counts from running Spring Boot services — starting with why three retries at three hops made 64 calls.

Distributed Systems
·7 min read

SQL Interview Questions for Experienced Engineers, Settled on Two Real Databases

The SQL questions experienced engineers get, run on PostgreSQL 17 and MySQL 8.4 — including a REPEATABLE READ that silently lost an update on one of them.

Databases
·7 min read

Java Multithreading Interview Questions, Answered by Running Them

Six questions from every Java concurrency interview, answered with a program's output rather than a definition — starting with how much a race really loses.

Java
·9 min read

Difference Between JDK, JRE and JVM: What Each One Actually Does

JDK, JRE and JVM explained by following one file from javac to output: what each layer holds, why Oracle stopped shipping a JRE, and which one to install.

Java