diff --git a/demos/gtk-demo/main.c b/demos/gtk-demo/main.c
index 4bfe34b..fb4d6bb 100644
--- a/demos/gtk-demo/main.c
+++ b/demos/gtk-demo/main.c
@@ -1,3 +1,21 @@
+/**************************************************      R E M E M B E R   !     *****************************************************/
+/*                                                                                                                                   */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk$ guix shell -m manifest.scm --check                 */
+/*   guix shell: vérification des variables d'environnement visibles depuis le shell « /gnu/store/ --- (a commit) --- /bin/bash »…   */
+/*   guix shell: Tout va bien ! Le shell a les bonnes variables d'environnement.                                                     */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk [env] $ cd builddir/                                */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk/builddir [env] $                                    */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk/builddir [env] $                                    */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree...way/gtk/builddir [env] $ clear && meson compile && demos/gtk-demo/gtk4-demo    */
+/*                                                                                                                                   */
+/*     -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --    A  Session   -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --      */
+/*                                                                                                                                   */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk/builddir [env] $ ctrl D  (avant de fermer builder)  */
+/*                                                                                                                                   */
+/*************************************************************************************************************************************/
+
+
+
 /* GTK Demo
  *
  * GTK Demo is a collection of useful examples to demonstrate
diff --git a/demos/gtk-demo/tree_store.c b/demos/gtk-demo/tree_store.c
index 2e48bb5..d37389a 100644
--- a/demos/gtk-demo/tree_store.c
+++ b/demos/gtk-demo/tree_store.c
@@ -1,3 +1,20 @@
+/**************************************************      R E M E M B E R   !     *****************************************************/
+/*                                                                                                                                   */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk$ guix shell -m manifest.scm --check                 */
+/*   guix shell: vérification des variables d'environnement visibles depuis le shell « /gnu/store/ --- (a commit) --- /bin/bash »…   */
+/*   guix shell: Tout va bien ! Le shell a les bonnes variables d'environnement.                                                     */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk [env] $ cd builddir/                                */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk/builddir [env] $                                    */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree...way/gtk/builddir [env] $ clear && meson compile && demos/gtk-demo/gtk4-demo    */
+/*                                                                                                                                   */
+/*     -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --    A  Session   -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --      */
+/*                                                                                                                                   */
+/*   jean@Project:~/Gem-Graph/gem-graph-client/tree (learning)/The_Gnome_way/gtk/builddir [env] $ ctrl D  (avant de fermer builder)  */
+/*                                                                                                                                   */
+/*************************************************************************************************************************************/
+
+
+
 /* Tree View/Tree Store
  *
  * The GtkTreeStore is used to store data in tree form, to be