ykpers (yubikey-personalization) is a library and command-line tool to perform
personalization of Yubico YubiKeys and is a reference implementation for
YubiKey configuration.

For challenge-response mode to work as a normal user, you will have to create
a 'yubikey' group and add your user to it. The recommended GID is 288. You can
create this by doing the following:
groupadd -g 288 yubikey

You can use the plugdev group (or another group) if you like, by passing a
group name to the script:
GROUPNAME=plugdev ./ykpers.SlackBuild

json-c is an optional dependency.