DIY Open-Source Yubikey for 30 RMB (Supports FIDO2 Hardware Security Key)

A DIY open-source Yubikey alternative has been created, supporting FIDO2 hardware security key functionality. This homemade version can be made for approximately 30 RMB. The project is detailed in a blog post, with a discussion also available on Hacker News. The blog post provides information on how to create the DIY FIDO key.