diff --git a/manifest.toml b/manifest.toml
index a3fe07d..c08ac6f 100644
--- a/manifest.toml
+++ b/manifest.toml
@@ -65,6 +65,7 @@ ram.runtime = "50M" # FIXME: replace with an **estimate** minimum ram requiremen
     [resources.install_dir]
 
     [resources.data_dir]
+    subdirs = ["media_cache"]
 
     [resources.permissions]
     main.url = "/"
diff --git a/scripts/_common.sh b/scripts/_common.sh
index 8430406..38a7aed 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -29,18 +29,6 @@ function set_node_vars {
     node_path=$nodejs_path:$(sudo -u $app sh -c 'echo $PATH')
 }
 
-function set_permissions {
-    mkdir -p "$install_dir/output/"{data,ui}
-    chown -R "root:$app" "$install_dir"
-    chmod -R g=u,g-w,o-rwx "$install_dir"
-
-    mkdir -p "$data_dir/media_cache"
-    chown -R "$app:$app" "$data_dir"
-
-    mkdir -p "/var/log/$app"
-    chmod -R o-rwx "/var/log/$app"
-}
-
 function build_libheif {
     export GOPATH="$install_dir/build/go"
     export GOCACHE="$install_dir/build/.cache"
@@ -82,7 +70,6 @@ function build_api {
 
     cp -T "$install_dir/sources/api/photoview" "$install_dir/output/photoview"
     cp -rT "$install_dir/sources/api/data" "$install_dir/output/data"
-    set_permissions
 }
 
 function build_ui {
diff --git a/scripts/change_url b/scripts/change_url
index 131f5d3..a19371b 100644
--- a/scripts/change_url
+++ b/scripts/change_url
@@ -26,6 +26,7 @@ ynh_change_url_nginx_config
 #=================================================
 
 ynh_add_config --template=".env" --destination="$install_dir/output/.env"
+chown "$app:$app" "$install_dir/output/.env"
 
 #=================================================
 # START SYSTEMD SERVICE
diff --git a/scripts/install b/scripts/install
index c9a91cb..e84a404 100755
--- a/scripts/install
+++ b/scripts/install
@@ -29,7 +29,10 @@ ynh_script_progression --message="Setting up source files..." --weight=10
 ynh_setup_source --dest_dir="$install_dir/sources"
 ynh_setup_source --source_id=libheif --dest_dir="$install_dir/libheif"
 
+mkdir -p "$install_dir/output/"{data,ui}
+
 chown -R "$app:$app" "$install_dir"
+chown -R "$app:$app" "$data_dir"
 
 #=================================================
 # BUILD APP
@@ -43,8 +46,6 @@ build_api
 ynh_script_progression --message="Building static UI files..." --weight=10
 build_ui
 
-set_permissions
-
 #=================================================
 # ADD A CONFIGURATION
 #=================================================
diff --git a/scripts/upgrade b/scripts/upgrade
index acf1fdd..f077fb1 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -47,8 +47,10 @@ ynh_script_progression --message="Upgrading source files..." --weight=5
 
 ynh_setup_source --dest_dir="$install_dir/sources" --full_replace=1
 ynh_setup_source --source_id=libheif --dest_dir="$install_dir/libheif" --full_replace=1
+mkdir -p "$install_dir/output/"{data,ui}
 
 chown -R "$app:$app" "$install_dir"
+chown -R "$app:$app" "$data_dir"
 
 #=================================================
 # BUILD APP
@@ -68,13 +70,7 @@ build_ui
 ynh_script_progression --message="Updating a configuration file..."
 
 ynh_add_config --template=".env" --destination="$install_dir/output/.env"
-
-#=================================================
-# SECURE FILES AND DIRECTORIES
-#=================================================
-
-# Set permissions on app files
-set_permissions
+chown "$app:$app" "$install_dir/output/.env"
 
 #=================================================
 # REAPPLY SYSTEM CONFIGURATIONS