The Iceberg data source just uses the Spark Session's global Hadoop configuration when constructing File System objects in HadoopTableOperations, Reader, and Writer. We propose support for specifying additional reader and writer-specific options to the Hadoop configuration. The data source can parse out options with the prefix iceberg.spark.hadoop.* and apply those to the Hadoop configuration that is sent to all uses of the Hadoop FileSystem API throughout the Spark DataSource.