diff --git a/config/services.yaml b/config/services.yaml
index 79b8ce2..83cd351 100644
--- a/config/services.yaml
+++ b/config/services.yaml
@@ -7,12 +7,15 @@
 # Put parameters here that don't need to change on each machine where the app is deployed
 # https://symfony.com/doc/current/best_practices.html#use-parameters-for-application-configuration
 parameters:
+    app.data_dir: '%kernel.project_dir%/var/data'
 
 services:
     # default configuration for services in *this* file
     _defaults:
         autowire: true      # Automatically injects dependencies in your services.
         autoconfigure: true # Automatically registers your services as commands, event subscribers, etc.
+        bind:
+            string $dataDir: '%app.data_dir%'
 
     # makes classes in src/ available to be used as services
     # this creates a service per class whose id is the fully-qualified class name