Storing Permanent Value in Flash? XIAO

Hello,

I’m using Arduino IDE, I’m trying to store a value in the seeeduino xiao that will be permanently written to the chip, so that even when new sketch is flashed it will still be there.

I have a calibration value that is unique to each Xiao I’m planning to deploy and what my code to be able to read this value in the sketch even if I need to update the program that is running on the Xiao later.

Hope that makes sense and I hope somebody can give me an idea how I can do this?

I know ESP32 has e-fuse you can write and burn, I want functionality like that.

Thanks