I am using a Silicon labs CP2102 chip. I have configured a custom USB VID and PID on the chip, and want to create a MacOs driver (or rather map this custom VID/PID to an existing driver) to make it accessible as a USB serial device from my Mac. Preferably I'd like to map my device to the com.apple.DriverKit-AppleUSBSLCOM.dext driver, but I think the generic USB serial driver (com.apple.DriverKit-AppleUSBSerial.dext) should work too. Silabs also has their own driver (com.silabs.cp210x.dext, downloadable from their web page), if for some reason it is easier to map to that than to one of the native drivers that could also work. Based on https://developer.apple.com/documentation/kernel/implementing_drivers_system_extensions_and_kexts#3616855 and https://developer.apple.com/documentation/driverkit/creating_a_driver_using_the_driverkit_sdk it should be possible to create a codeless dext, which just inherits from e.g. IOUserUSBSerial. I've tried both creating just a DriverKit driver and putting it under /Library/DriverExtensions/ and creating a (default) app and adding a DriverKit driver to it, and putting the app in my /Applications/ folder, but neither works for me. My driver implementation is just this: #include <USBSerialDriverKit/IOUserUSBSerial.iig> class MyDriver: public IOUserUSBSerial { }; and my IOKitPersonalities looks like this: <key>IOKitPersonalities</key> <dict> <key>MyDriver</key> <dict> <key>CFBundleIdentifier</key> <string>com.mydriver.MyDriverApp.MyDriver</string> <key>IOClass</key> <string>IOUserUSBSerial</string> <key>IOMatchCategory</key> <string>com.mydriver.MyDriverApp.MyDriver</string> <key>IOProviderClass</key> <string>IOUSBHostInterface</string> <key>IOUserClass</key> <string>MyDriver</string> <key>IOUserServerName</key> <string>com.mydriver.MyDriverApp.MyDriver</string> <key>bConfigurationValue</key> <integer>1</integer> <key>bInterfaceNumber</key> <integer>0</integer> <key>idProduct</key> <integer>(my custom PID, decimal value)</integer> <key>idVendor</key> <integer>(my custom VID, decimal value)</integer> </dict> </dict> I've disabled SIP and enabled developer mode (systemextensionsctl developer on), though I'm not sure if it's needed. I've scanned through the system logs and looked at the ioreg output. When I connect a CP2102 chip with default VID and PID, I can see that it maps to the native com.apple.DriverKit-AppleUSBSLCOM.dext driver. When I connect the same chip with my custom VID and PID, I don't see any trace of my driver being used. I can see it in the System Information app, but it doesn't map to my driver. I'm currently suspecting it is an Entitlements issue. In my app I have an Entitlements file, where I've added DriverKit USB Transport and DriverKit Serial Family. Do I need something like this for the driver target? There is no default Entitlements file there, but maybe I should create one? Or is there something else I'm missing? I've also noted one odd thing: When I install my app I can see a system log entry, complaining that "package type not SYSX" (for my driver). But I don't think it should be a SYSX package? It's currently specified as a DEXT package.