Spring Boot applications running as GraalVM native images start in milliseconds, use a fraction of the memory, and fit in tiny containers. The tradeoff is a longer build time. In 2026, with Spring Boot 4 and GraalVM 24, native images are production-ready for most Spring applications. This guide covers everything: what Spring AOT does, how to build your first native image, how to fix the common issues, and how to add native builds to CI.

Caching reduces database load and response latency. Spring Boot’s cache abstraction lets you add caching with annotations, then swap the implementation (Caffeine, Redis, multi-level) without changing your business code. This guide covers Caffeine for in-JVM caching, Redis for distributed caching, and a multi-level cache that combines both. Spring Cache Abstraction Spring’s cache abstraction uses three annotations: Annotation Behaviour @Cacheable Cache the return value. On subsequent calls, return from cache without executing the method.

JPA makes database access simple. It also makes it dangerously easy to write code that fires 100 SQL queries to load 10 records. The N+1 problem alone has caused more production performance incidents than almost any other JPA issue. This guide covers how to find and fix the five most common JPA performance problems: N+1 queries, LazyInitializationException, over-fetching, poor connection pool sizing, and Hibernate 6 breaking changes. Enable SQL Logging First Before optimizing anything, see exactly what queries are firing:

Virtual Threads landed in Java 21 as a stable feature, and Spring Boot 3.2 added first-class support with a single property. The promise: write simple blocking code and get WebFlux-level throughput. The reality is mostly true — with some important exceptions. This article covers what Virtual Threads actually are, how to enable them in Spring Boot, real benchmark numbers, the three pitfalls that will silently destroy your performance, and a decision framework for when to use them (and when not to).

Every year, someone asks: “Should we use Spring Boot or Quarkus?” In 2026, both frameworks are mature, both run natively, and both work well on Kubernetes. The differences come down to developer experience, ecosystem size, and specific performance characteristics. This is an honest comparison with real numbers, not marketing claims. The Frameworks at a Glance Spring Boot 4 (November 2025): Built on Spring Framework 7. The de-facto standard for enterprise Java.