--- title: Application Startup Tracking in Spring | daily.dev description: Spring provides the ApplicationStartup interface to track and analyze application context creation during startup. Three implementations are covered:... canonical: https://daily.dev/posts/application-startup-tracking-in-spring-ry8iq2xdy twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Application Startup Tracking in Spring | daily.dev og:description: Spring provides the ApplicationStartup interface to track and analyze application context creation during startup. Three implementations are covered:... og:url: https://daily.dev/posts/application-startup-tracking-in-spring-ry8iq2xdy og:image: https://api.daily.dev/og/posts/Ry8iq2XdY.png og:image:alt: Application Startup Tracking in Spring og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Application Startup Tracking in Spring **[Baeldung](https://daily.dev/sources/baeldung)** · 7 min read · 6 upvotes · 0 comments ## Summary Spring provides the ApplicationStartup interface to track and analyze application context creation during startup. Three implementations are covered: DefaultApplicationStartup (no-op), BufferingApplicationStartup (stores events in memory, accessible via actuator endpoint or programmatically), and FlightRecorderApplicationStartup (integrates with Java Flight Recorder/JMC). The tutorial shows how to configure each, access recorded startup steps, add custom steps using @PostConstruct, write tests with SpringBootTest.UseMainMethod.ALWAYS, and implement a fully custom ApplicationStartup for real-time monitoring during context creation. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do I access the BufferingApplicationStartup timeline through the Spring Boot actuator endpoint? Enable the startup endpoint with management.endpoints.web.exposure.include=startup in application properties, then call GET or POST on /actuator/startup. Both return the same recorded timeline of startup steps, but POST also clears the buffer afterward, while GET only returns a snapshot without clearing it. This only works when BufferingApplicationStartup is configured; other implementations return a 404 Not Found error. _Developers instrumenting Spring Boot startup performance track actuator changes like this via daily.dev._ ### What is the difference between BufferingApplicationStartup and FlightRecorderApplicationStartup in Spring Boot? BufferingApplicationStartup records startup events in memory and exposes them via an actuator endpoint or programmatic access to the application context, useful for testing and custom analysis. FlightRecorderApplicationStartup instead writes startup metrics into a Java Flight Recorder (JFR) file, viewable in Java Mission Control under the 'Spring Application' category, requiring a JVM flag like -XX:StartFlightRecording:filename=recording.jfr,duration=20s. _Engineers comparing Spring startup monitoring options follow tool trade-offs like these on daily.dev._ ### How do I add a custom startup step to Spring's ApplicationStartup for a specific bean's initialization? Retrieve the ApplicationStartup instance from the ConfigurableApplicationContext, then call applicationStartup.start("step-name") to create a StartupStep, tag it with descriptive key-value pairs, and call end() when finished. This appears in the actuator timeline nested under the bean's spring.beans.instantiate parent step, letting you measure specific initialization work like database connections. _Developers diagnosing slow bean initialization can track custom startup steps like this via daily.dev._ ## Similar posts on daily.dev - [Spring Boot tutorial: Get started with Spring Boot](https://daily.dev/posts/spring-boot-tutorial-get-started-with-spring-boot-itnz41zwx) · InfoWorld · 1 upvotes · 0 comments - [Crafting Spring Boot Starters](https://daily.dev/posts/crafting-spring-boot-starters-fxxg2w0lt) · Wim Deblauwe · 1 upvotes · 0 comments - [OpenTelemetry Guide](https://daily.dev/posts/opentelemetry-guide-gk7sxbvat) · Foojay.io · 10 upvotes · 0 comments - [Implement Distributed Tracing with Spring Boot 3](https://daily.dev/posts/implement-distributed-tracing-with-spring-boot-3-vwpklksid) · Last9 · 2 upvotes · 0 comments --- Tags: [#performance](https://daily.dev/tags/performance), [#java](https://daily.dev/tags/java), [#spring-boot](https://daily.dev/tags/spring-boot) [View this post on daily.dev](https://daily.dev/posts/application-startup-tracking-in-spring-ry8iq2xdy) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Application Startup Tracking in Spring","url":"https://daily.dev/posts/application-startup-tracking-in-spring-ry8iq2xdy","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/application-startup-tracking-in-spring-ry8iq2xdy"},"datePublished":"2026-07-25T19:31:49.820Z","dateModified":"2026-09-14T06:02:06.695Z","description":"Spring provides the ApplicationStartup interface to track and analyze application context creation during startup. 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