June 2026 monthly summary for elastic/elasticsearch focused on batch processing data integrity. Key bug fix delivered a robust validation to enforce uniform primary terms across all operations within a batch. Extended the existing validation in processSubBatch to check primaryTerm in addition to operation origin; if a batch contains differing primary terms, production will now throw an IllegalStateException to prevent data corruption. The change is tied to commit c9ba1a57fccb6bb643ccb951a8b931356da03787, underscoring a concrete, production-facing fix. Business value includes safer batch writes, improved data consistency for bulk workloads, and reduced risk of silent corruption. Technologies used include Java, batch processing patterns, validation logic, and standard exception handling.