file_picker: one user intent across six platforms file_picker is useful because it focuses on filters, multiple selection, bytes, and platform-specific paths. The important engineering move is to place the package behind a clear boundary, so your Flutter UI depends on a stable capability rather than a vendor-shaped API. What the library should own Keep package calls inside a named adapter or feature boundary. Make lifecycle, errors, and loading state part of a testable contract. Expose only the capability the app needs; hide implementation details from the whole tree. A focused starting point final result = await FilePicker .platform. pickFiles ( allowMultiple : true , type : FileType .custom, allowedExtensions : [ 'pdf' , 'png' ], ); for ( final file in result ? .files ?? < PlatformFile > []) { upload (file.name, file.bytes, file.path); } Production checklist Read the README and changelog for the exact version you pin. Add ...