Maryam Shahid focused on enhancing SQL query input validation and error handling in the apache/druid repository during February 2026. She addressed a key bug by refining how user errors are classified, ensuring that invalid SQL inputs now return a 400 (USER/INVALID_INPUT) code instead of a generic 500, which streamlines diagnostics and reduces support overhead. Her technical approach involved adding instanceof checks for RexLiteral.value() to prevent incorrect casting in SQL aggregators, thereby reducing runtime errors. Working primarily with Java and SQL, Maryam’s contributions improved the reliability of error reporting and accelerated the triage process for invalid user queries.