Worked on the citusdata/citus repository to address a critical server crash in distributed transaction handling. Focused on backend development and distributed systems, the solution involved adding a pre-check for backend data availability before assigning distributed transactions. By ensuring that an ERROR is returned when backend data is not ready, rather than allowing a crash, the fix improved error handling and system robustness. Implemented in C, this change resolved Bug 3697586 and enhanced fault tolerance across clustered nodes. The update also improved observability and troubleshooting for distributed transaction assignment, reducing production downtime and supporting more reliable distributed operations.