diff --git a/default.nix b/default.nix
index a6117bc..bb5d609 100644
--- a/default.nix
+++ b/default.nix
@@ -70,10 +70,11 @@ let
       rm -f $out/opt/usda-vision/.env
       
       # Update docker-compose.yml to use /var/lib/usda-vision/.env
-      # Use temp file in /tmp to avoid permission issues
+      # Use temp file in /tmp and remove old file before moving
       if [ -f $out/opt/usda-vision/docker-compose.yml ]; then
         ${pkgs.gnused}/bin/sed 's|env_file:.*management-dashboard-web-app/\.env|env_file: /var/lib/usda-vision/.env|g; s|\./management-dashboard-web-app/\.env|/var/lib/usda-vision/.env|g' \
           $out/opt/usda-vision/docker-compose.yml > /tmp/docker-compose.yml.tmp
+        rm $out/opt/usda-vision/docker-compose.yml
         mv /tmp/docker-compose.yml.tmp $out/opt/usda-vision/docker-compose.yml
       fi