# Modifying Linked System-Level Files

For most use cases, there is no need to modify the linked system-level files. However, if such modification is necessary, it can be done in either of two ways:

1. Modify the files directly in the RSL15 CMSIS-Pack. Be aware that any other project linking to the modified files is affected by your changes as well.
2. Copy the file to the workspace, and break the link to the CMSIS-Pack.

IMPORTANT: Any modification to the CMSIS-Pack structure will require manual maintenance when you update to a new CMSIS-Pack version. Consider this before modifying the linked system-level files.