diff --git a/scripts/_common.sh b/scripts/_common.sh
index cfbfeec..344f5b1 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -38,12 +38,12 @@ rp_validate_assets_path() {
         try_files="try_files /dev/null @${app}--proxy;"
     else
         if [ ! -d "$assets_path" ]; then
-            ynh_die "Requested assets path "$assets_path" does not exist" 1
+            ynh_die "Requested assets path ${assets_path} does not exist" 1
         fi
 
         if [[ ! "$assets_path" =~ /$ ]]; then
             # Append missing trailing /
-            assets_path=""${assets_path}"/"
+            assets_path="${assets_path}/"
         fi
 
         assets_alias="alias $assets_path;"
@@ -58,7 +58,7 @@ rp_handle_webroot() {
         path_slash="/"
         redirect_block="# Not needed for webroot"
     else
-        path_slash=""$path"/"
-        redirect_block="location = "$path" { return 302 "$path_slash"; }"
+        path_slash="$path"/
+        redirect_block="location = ${path} { return 302 ${path_slash}; }"
     fi
 }
diff --git a/scripts/change_url b/scripts/change_url
index e73eb60..bc546d8 100644
--- a/scripts/change_url
+++ b/scripts/change_url
@@ -36,7 +36,7 @@ ynh_add_nginx_config
 if [[ "$old_domain" != "$new_domain" ]]; then
 	new_nginx_conf_path=/etc/nginx/conf.d/$new_domain.d/$app.conf
 	ynh_delete_file_checksum --file="$nginx_conf_path"
-	mv $nginx_conf_path $new_nginx_conf_path
+	mv "${nginx_conf_path}" "${new_nginx_conf_path}"
 	ynh_store_file_checksum --file="$new_nginx_conf_path"
 fi
 
diff --git a/scripts/remove b/scripts/remove
index 984660f..46c23e1 100644
--- a/scripts/remove
+++ b/scripts/remove
@@ -14,7 +14,7 @@ source /usr/share/yunohost/helpers
 #=================================================
 
 # Remove configuration files
-ynh_secure_remove /etc/nginx/conf.d/$domain.d/$app.conf
+ynh_secure_remove "/etc/nginx/conf.d/${domain}.d/${app}.conf"
 
 #=================================================
 # END OF SCRIPT
diff --git a/scripts/upgrade b/scripts/upgrade
index 3030cdc..1ed1493 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -1,4 +1,3 @@
-
 #!/bin/bash
 
 #=================================================