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.