NIL**Update 2020**: This method may certainly not work anymore but I
don't have a Guix installation to try.
I'm new to Guix, it's a wonderful system but it's such different than
any other usual linux distribution that it's hard to achieve some
basics tasks. As Guix is 100% free/libre software, Firefox has been
removed and replaced by icecat. This is nearly the same software but
some "features" has been removed (like webRTC) for some reasons
(security, freedom). I don't blame Guix team for that, I understand
the choice.
But my problem is that I need Firefox. I finally achieve to get it
working from the official binary downloaded from mozilla website.
You need to install some packages to get the libraries, which will
become available under your profile directory. Then, tells firefox to
load libraries from there and it will start.
guix package -i glibc glib gcc gtk+ libxcomposite dbus-glib libxt
LD_LIBRARY_PATH=~/.guix-profile/lib/ ~/.guix-profile/lib/ld-linux-x86-64.so.2 ~/firefox_directory/firefox
Also, it seems that running icecat and firefox simultanously works,
they store data in ~/.mozilla/icecat and ~/.mozilla/firefox so they
are separated.