When using this awesome piece of software, you probably want to give a miss to the "blue pill" board recommended in the README file, and go instead with ST-Link v.2 clone, which has identical hardware and pricetag, while being considerably more portable:
Absolutely agree about that, at least it has enclosure. I will check if i have one, i might port software to this hardware too, it should be trivial.
I might try to make 3d printed enclosure for blue pill as well.
https://blog.danman.eu/2-usb-crypto-token-for-use-with-gpg-a...