Worked on the apache/ignite repository to enhance cluster stability by addressing a critical issue in the cluster join process. Focused on backend development and distributed systems using Java, the work involved implementing a robust solution to handle SecurityException scenarios during node joins, ensuring that missing permissions no longer cause node crashes. Instead, the system now returns a failed future with the original exception, improving error propagation and observability. To validate this behavior, a dedicated regression test was added to cover activation with persistence under restricted permissions. This targeted fix improved reliability and expanded test coverage for production deployments in secure environments.