Nitrokey is open source (hardware and software). They claim the "installed firmware can be exported and verified, preventing attackers from inserting backdoors

Nitrokey is open source (hardware and software). They claim the "installed firmware can be exported and verified, preventing attackers from inserting backdoors into products during shipping". (https://www.nitrokey.com/ https://www.nitrokey.com/) They list Google as one of their customers. Also if you're a Linux kernel developer you get one for free: https://www.nitrokey.com/news/2018/nitrokey-partners-linux-foundation-equip-all-linux-kernel-developers-nitrokey-usb-keys https://www.nitrokey.com/news/2018/nitrokey-partners-linux-f...