;; What follows is a "manifest" equivalent to the command line you gave.
;; You can store it in a file that you may then pass to any 'guix' command
;; that accepts a '--manifest' (or '-m') option.

(specifications->manifest (list "gcc-toolchain"
                                "libffi"
                                "chibi-scheme"
                                "chicken"
                                "guile-next"
                                "gambit-c"
                                "gerbil"
                                "racket"
                                "mosh"
                                "stklos"
                                "openjdk"))