Spring: Lazy initialisation trades startup time for late failures

spring.main.lazy-initialization=true speeds up boot but moves configuration errors to the first request.

Code

// application.yml
spring:
  main:
    lazy-initialization: true

// Keep one bean eager despite the global setting:
@Component
@Lazy(false)
class MustExistAtStartup { }

Output

Startup: 1.2s instead of 3.8s
But a typo'd datasource URL now fails on the first request, in production.

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Published 2026-08-11