diff --git a/nixos/modules/config/debug-info.nix b/nixos/modules/config/debug-info.nix
index 49991d22a93..2942ae5905d 100644
--- a/nixos/modules/config/debug-info.nix
+++ b/nixos/modules/config/debug-info.nix
@@ -30,14 +30,15 @@ with lib;
   };
 
 
-  config = {
+  config = mkIf config.environment.enableDebugInfo {
 
     # FIXME: currently disabled because /lib is already in
     # environment.pathsToLink, and we can't have both.
     #environment.pathsToLink = [ "/lib/debug/.build-id" ];
 
-    environment.extraOutputsToInstall =
-      optional config.environment.enableDebugInfo "debug";
+    environment.extraOutputsToInstall = [ "debug" ];
+
+    environment.variables.NIX_DEBUG_INFO_DIRS = [ "/run/current-system/sw/lib/debug" ];
 
   };