Top 3 tricky Senior Developer Interview Questions & Answers | Spring boot Microservice | Code Decode

In this episode of Code Decode, the speaker discusses frequently asked Spring Boot and microservice interview questions for senior Java developers in 2025, focusing on optimizing Spring Boot applications for cold startup time. The speaker explains what cold start is, why it's a problem, and provides real-world examples. The speaker then details methods to reduce startup time, including analyzing bottlenecks with Actuator, lazy initialization of beans, removing unused auto-configurations, tweaking database initialization, trimming starter dependencies, and using AOT plus native images with GraalVM. Additionally, the speaker covers common production issues faced in Spring Boot microservices, such as memory leaks, thread pool exhaustion, cold start delays, cascading failures, unbounded log files, misconfigured security, lack of observability, version mismatches, illogical retry options, and hardcoding properties, offering proactive solutions for each. Lastly, the speaker addresses handling backward-incompatible API changes through versioning, feature toggles, and gradual rollouts.