Is this directory hierarchy within your app’s container? Or have you got access to it otherwise, for example, using one of the document access APIs? No - the tree is question is users Documents / Mobile Documents (.../mobile/Library/Mobile%20Documents/comappleCloudDocs/Documents), the access is gained via security scoped urls (I guess it is document api). I wonder if I can just add the relevant entitlements to the app / skip the sandboxing altogether - it will be distributed in-house only. The main problem however is still the open-file limit (if no other API can be used for the task)