{ pkgs, ... }: { # Create the plugdev group (required for user-space USB access to YubiKey) users.groups.plugdev = {}; # Enable PC/SC daemon — required for GPG smartcard (gpg --card-status) and YubiKey services.pcscd.enable = true; # udev rules so the YubiKey gets plugdev group ownership and correct permissions services.udev.packages = with pkgs; [ yubikey-personalization libu2f-host ]; # CCID driver for smartcard access (required for YubiKey CCID functionality) services.pcscd.plugins = [ pkgs.ccid ]; # YubiKey management tools environment.systemPackages = with pkgs; [ yubikey-manager # ykman CLI yubikey-personalization # ykpers / ykchalresp yubico-piv-tool # PIV applet management ]; }