<rekado>dijong: you’d have to install them in the same transaction, but even then I think that “guix package -i” prevents that due to the potential for conflicts.
<rekado>“guix environment --ad-hoc” would allow it, though.
<dijong>rekado: thank you, installing them via "guix environment --ad-hoc gtk+@2:out gtk+@3:bin gtk+@3:out" seemed to work -- but only for that shell, how can i do it for my user's global (default) environment?
<rekado>dijong: this is not possible at the moment. It’s a missing feature. See bug #30830.