Cronflower Brings Distributed Cron Scheduling to Multi-Instance Spring Boot Apps

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Cronflower is a new open-source distributed scheduler designed to solve the limitations of Spring Boot's built-in @Scheduled annotation, which only runs within a single JVM. When scaling to multiple instances, @Scheduled can trigger duplicate job executions, a problem Cronflower addresses by separating infrastructure into dedicated scheduler nodes and executor applications. Scheduler nodes form a leader-elected cluster that manages task state and dispatch, while executors declare tasks using a custom @Task annotation with support for cron expressions, fixed intervals, and ISO-8601 durations. The framework also includes production-ready features such as configurable retry with back-off, per-run timeouts, misfire policies, and bounded repeat counts. Task execution history, run counts, and next fire times are visible through a built-in console, making it easier to monitor distributed job activity.

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