Not technically not a bug because the doc says ... 2.6.2 X11 Fonts
The ‘fontconfig’ package in Guix looks for fonts in ‘$HOME/.guix-profile’ by default. Thus, to allow graphical applications installed with Guix to display fonts, you have to install fonts with Guix as well. But it does seem counter-intuitive that emacs 'M-x list-fontsets' gives ... Fontset: -*-*-*-*-*-*-*-*-*-*-*-*-fontset-default Fontset: -*-fixed-medium-r-normal-*-16-*-*-*-*-*-fontset-standard Fontset: -urw-Nimbus Mono L-normal-normal-normal-*-13-*-*-*-m-0-fontset-startup ... when the system package list is ... % *Guix Package L... 5437 Guix-Output-List [...] emacs 24.5 out Yes The extensible, customizable, self-documenting text editor [...] font-dejavu 2.34 out Yes Vera font family derivate with additional characters [...]