diff --git a/scripts/_common.sh b/scripts/_common.sh
index 09a83c3..281512f 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -3,7 +3,7 @@
 #=================================================
 
 systemd_match_start_line='Starting new Web server: tcp:127.0.0.1:'
-ssh_port=$(yunohost settings get security.ssh.ssh_port)
+ssh_port="$(yunohost settings get security.ssh.ssh_port)"
 
 #=================================================
 # DEFINE ALL COMMON FONCTIONS
@@ -15,10 +15,10 @@ _set_permissions() {
     chmod +x "$install_dir/gitea"
 
     chown -R "$app:$app" "$data_dir"
-    find $data_dir \(   \! -perm -o= \
-                     -o \! -user $app \
-                     -o \! -group $app \) \
-                   -exec chown $app:$app {} \; \
+    find "$data_dir" \(   \! -perm -o= \
+                     -o \! -user "$app" \
+                     -o \! -group "$app" \) \
+                   -exec chown "$app:$app" {} \; \
                    -exec chmod u=rwX,g=rX,o= {} \;
     chmod -R u=rwX,g=,o= "$data_dir/.ssh"
 
diff --git a/scripts/backup b/scripts/backup
index 27468e1..b413ff1 100644
--- a/scripts/backup
+++ b/scripts/backup
@@ -9,7 +9,7 @@ source ../settings/scripts/_common.sh
 source /usr/share/yunohost/helpers
 
 
-if systemctl is-active $app.service --quiet; then
+if systemctl is-active "$app".service --quiet; then
     ynh_print_warn --message="It's hightly recommended to make your backup when the service is stopped. Please stop $app service with this command before to run the backup 'systemctl stop $app.service'"
 fi
 
diff --git a/scripts/install b/scripts/install
index 41504b4..5ea75e6 100644
--- a/scripts/install
+++ b/scripts/install
@@ -17,10 +17,10 @@ source /usr/share/yunohost/helpers
 
 ynh_script_progression --message='Creating base directory...'
 
-if [ -n "$(ls -A $data_dir)" ]; then
+if [ -n "$(ls -A "$data_dir")" ]; then
     old_data_dir_path="${data_dir}_$(date '+%Y%m%d.%H%M%S')"
     ynh_print_warn "Data directory was not empty. Data was moved to $old_data_dir_path"
-    mkdir -p $old_data_dir_path
+    mkdir -p "$old_data_dir_path"
     mv -t "$old_data_dir_path" "$data_dir"/*
 fi
 
@@ -42,10 +42,10 @@ _set_permissions
 
 ynh_script_progression --message="Configuring application, step 1/2..."
 
-internal_token=$(ynh_exec_as "$app" "$install_dir/gitea" generate secret INTERNAL_TOKEN)
-secret_key=$(ynh_exec_as "$app" "$install_dir/gitea" generate secret SECRET_KEY)
-lfs_jwt_secret=$(ynh_exec_as "$app" "$install_dir/gitea" generate secret JWT_SECRET)
-jwt_secret=$(ynh_exec_as "$app" "$install_dir/gitea" generate secret JWT_SECRET)
+internal_token="$(ynh_exec_as "$app" "$install_dir/gitea" generate secret INTERNAL_TOKEN)"
+secret_key="$(ynh_exec_as "$app" "$install_dir/gitea" generate secret SECRET_KEY)"
+lfs_jwt_secret="$(ynh_exec_as "$app" "$install_dir/gitea" generate secret JWT_SECRET)"
+jwt_secret="$(ynh_exec_as "$app" "$install_dir/gitea" generate secret JWT_SECRET)"
 
 ynh_app_setting_set --app="$app" --key=internal_token --value="$internal_token"
 ynh_app_setting_set --app="$app" --key=secret_key --value="$secret_key"
diff --git a/scripts/upgrade b/scripts/upgrade
index 7f78e81..0d3cfa0 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -9,7 +9,7 @@
 source _common.sh
 source /usr/share/yunohost/helpers
 
-upgrade_type=$(ynh_check_app_version_changed)
+upgrade_type="$(ynh_check_app_version_changed)"
 
 #=================================================
 # STANDARD UPGRADE STEPS
@@ -69,12 +69,12 @@ chmod -R u=rwX,g=rX,o= "$install_dir"
 chmod +x "$install_dir/gitea"
 
 if [[ -z "${internal_token:-}" ]]; then
-    internal_token=$(ynh_exec_as "$app" "$install_dir/gitea" generate secret INTERNAL_TOKEN)
+    internal_token="$(ynh_exec_as "$app" "$install_dir/gitea" generate secret INTERNAL_TOKEN)"
     ynh_app_setting_set --app="$app" --key=internal_token --value="$internal_token"
 fi
 
 if [[ -z "${secret_key:-}" ]]; then
-    secret_key=$(ynh_exec_as "$app" "$install_dir/gitea" generate secret SECRET_KEY)
+    secret_key="$(ynh_exec_as "$app" "$install_dir/gitea" generate secret SECRET_KEY)"
     ynh_app_setting_set --app="$app" --key=secret_key --value="$secret_key"
 fi
 
@@ -85,12 +85,12 @@ if [[ -n "${lfs_key:-}" ]]; then
 fi
 
 if [[ -z "${lfs_jwt_secret:-}" ]]; then
-    lfs_jwt_secret=$(ynh_exec_as "$app" "$install_dir/gitea" generate secret JWT_SECRET)
+    lfs_jwt_secret="$(ynh_exec_as "$app" "$install_dir/gitea" generate secret JWT_SECRET)"
     ynh_app_setting_set --app="$app" --key=lfs_jwt_secret --value="$lfs_jwt_secret"
 fi
 
 if [[ -z "${jwt_secret:-}" ]]; then
-    jwt_secret=$(ynh_exec_as "$app" "$install_dir/gitea" generate secret JWT_SECRET)
+    jwt_secret="$(ynh_exec_as "$app" "$install_dir/gitea" generate secret JWT_SECRET)"
     ynh_app_setting_set --app="$app" --key=jwt_secret --value="$jwt_secret"
 fi
 
@@ -98,7 +98,7 @@ fi
 # MIGRATION STEP Fix regression linked to 77c3678 and #76
 #=================================================
 
-list_param_sql=$(yunohost user list --output-as json | jq -c '.users | keys' | sed 's|\[|\(|' | sed 's|\]|\)|')
+list_param_sql="$(yunohost user list --output-as json | jq -c '.users | keys' | sed 's|\[|\(|' | sed 's|\]|\)|')"
 ynh_replace_string --match_string=__APP__ --replace_string="$app" --target_file=./fix_user_db_for_local_users.sql
 ynh_replace_string --match_string=__USER_LIST__ --replace_string="$list_param_sql" --target_file=./fix_user_db_for_local_users.sql
 ynh_mysql_connect_as "$db_user" "$db_pwd" "$db_name" < ./fix_user_db_for_local_users.sql