Worked on the Rdatatable/data.table repository to enhance developer guidance for combining results from the j expression with the by argument. Focused on updating documentation to clarify that results are merged using rbindlist, which does not preserve names, ensuring more predictable and reproducible outputs for users. This documentation improvement addressed a common source of confusion, supporting better onboarding and reducing support queries. The work involved R programming and data manipulation, with an emphasis on clear technical communication. No major bug fixes were required during this period, as the primary contribution centered on improving usability and workflow reliability through targeted documentation updates.