Emacs/Guix: Add system installation command.

.emacs.d/lisp/init-guix.el

@@ -193,7 +193,8 @@ If MANIFEST is nil, it is queried from the manifests found in `ambrevar/guix-man
   (require 'init-eshell)                ; For `ambrevar/prefer-eshell'.
   (let* ((guix (if channel
                    (let ((dest (expand-file-name
-                                manifest-name
+                                ;; TODO: What name should we use with multiple manifests?
+                                (first (first manifests))
                                 ambrevar/guix-extra-channels)))
                      (make-directory dest 'parents)
                      (format "guix pull --channels=%s --profile=%s/guix && %s/guix/bin/guix"
@@ -276,6 +277,27 @@ With a prefix argument, query for a channel specification file."
   (dolist (mode '(normal insert))
     (evil-global-set-key mode (kbd "C-x c G") #'ambrevar/guix-install-manifests)))
 
+(defun ambrevar/guix-install-system (&optional system)
+  "Install Guix system.
+
+System is queried from those found in `ambrevar/guix-system-directory'. "
+  (interactive)
+  (let* ((system-pair (ambrevar/guix-query-system system))
+         (system-name (first system-pair))
+         (system (second system-pair)))
+    (funcall (if ambrevar/prefer-eshell
+                 'ambrevar/run-in-eshell
+               'ambrevar/run-in-shell)
+             (string-join
+              (list "sudo" "-E"  "guix" "system" "-L" ambrevar/guix-system-directory
+                    "reconfigure" system)
+              " "))))
+(global-set-key (kbd "C-x c S") #'ambrevar/guix-install-system)
+(with-eval-after-load 'evil
+  ;; For some reason `global-set-key' does not work for Evil at this point.
+  (dolist (mode '(normal insert))
+    (evil-global-set-key mode (kbd "C-x c S") #'ambrevar/guix-install-system)))
+
 ;; TODO: See `guix-apply-manifest' and expand on it.
 ;; TODO: Use --max-jobs=N.