diff --git a/nix/nixos-module/container/bird.nix b/nix/nixos-module/container/bird.nix
index 9cda861..5aeb76c 100644
--- a/nix/nixos-module/container/bird.nix
+++ b/nix/nixos-module/container/bird.nix
@@ -35,29 +35,31 @@ in
       protocol kernel K4 {
         learn;
         ipv4 {
-          ${lib.optionalString (!isUpstream) ''
-            export all;
-          ''}
-          ${lib.optionalString isUpstream ''
-            # Do not set another default route on upstreams
-            export where net != 0.0.0.0/0;
-            # Learn the upstream default route
-            import where net = 0.0.0.0/0;
-          ''}
+          ${if isUpstream
+            then ''
+              # Install all routes but the default route on upstreams
+              export where net != 0.0.0.0/0;
+              # Learn the upstream default route
+              import where net = 0.0.0.0/0;
+            ''
+            else ''
+              export all;
+            ''}
         };
       }
       protocol kernel K6 {
         learn;
         ipv6 {
-          ${lib.optionalString (!isUpstream) ''
-            export all;
-          ''}
-          ${lib.optionalString isUpstream ''
-            # Do not set another default route on upstreams
-            export where net != ::/0;
-            # Learn the upstream default route
-            import where net = ::/0;
-          ''}
+          ${if isUpstream
+            then ''
+              # Install all routes but the default route on upstreams
+              export where net != ::/0;
+              # Learn the upstream default route
+              import where net = ::/0;
+            ''
+            else ''
+              export all;
+            ''}
         };
       }
       protocol device {