burn bootloader to atsamd21

dear fellow makers,

i have been using arduino for just under a year now and am familiar enough with the coding and sketch uploading but am looking into making my project smaller. i have chosen to use an atsamd21 fo the controller on my shrinked arduino. so here is my question:

how would i burn the arduino zero bootloader onto an atsamd21?

researching has not yielded much that i have seen. if i have missed an obvious tutorial or guid please redirect me.

all help is much appreciated,
vesper krate

You'll need an external JTAG programming device that support SWD. It would be easiest using an Atmel programmer like the "Atmel ICE" (current) or "JTAG ICE 3" (last generation.)

thank you, is there any guide or instructions for doing so?

https://github.com/femtoduino/femto-usb looks like useful instructions. There would also be the manuals and whatnot that come with the Atmel programmers; there's nothing magic about the bootloader; you burn it like you'd burn any other program using the tool...