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.