diff --git a/pkgs/build-support/rust/hooks/default.nix b/pkgs/build-support/rust/hooks/default.nix
index 0814f78edfef..1cfb56f785c0 100644
--- a/pkgs/build-support/rust/hooks/default.nix
+++ b/pkgs/build-support/rust/hooks/default.nix
@@ -26,9 +26,8 @@
     };
     passthru.tests = {
       test = tests.rust-hooks.cargoBuildHook;
-    }
-    // lib.optionalAttrs (stdenv.hostPlatform.isLinux) {
-      testCross = pkgsCross.riscv64.tests.rust-hooks.cargoBuildHook;
+      ${if stdenv.hostPlatform.isLinux then "testCross" else null} =
+        pkgsCross.riscv64.tests.rust-hooks.cargoBuildHook;
     };
   } ./cargo-build-hook.sh;
 
@@ -40,9 +39,8 @@
     };
     passthru.tests = {
       test = tests.rust-hooks.cargoCheckHook;
-    }
-    // lib.optionalAttrs (stdenv.hostPlatform.isLinux) {
-      testCross = pkgsCross.riscv64.tests.rust-hooks.cargoCheckHook;
+      ${if stdenv.hostPlatform.isLinux then "testCross" else null} =
+        pkgsCross.riscv64.tests.rust-hooks.cargoCheckHook;
     };
   } ./cargo-check-hook.sh;
 
@@ -53,9 +51,8 @@
     };
     passthru.tests = {
       test = tests.rust-hooks.cargoInstallHook;
-    }
-    // lib.optionalAttrs (stdenv.hostPlatform.isLinux) {
-      testCross = pkgsCross.riscv64.tests.rust-hooks.cargoInstallHook;
+      ${if stdenv.hostPlatform.isLinux then "testCross" else null} =
+        pkgsCross.riscv64.tests.rust-hooks.cargoInstallHook;
     };
   } ./cargo-install-hook.sh;
 
@@ -67,9 +64,8 @@
     };
     passthru.tests = {
       test = tests.rust-hooks.cargoNextestHook;
-    }
-    // lib.optionalAttrs (stdenv.hostPlatform.isLinux) {
-      testCross = pkgsCross.riscv64.tests.rust-hooks.cargoNextestHook;
+      ${if stdenv.hostPlatform.isLinux then "testCross" else null} =
+        pkgsCross.riscv64.tests.rust-hooks.cargoNextestHook;
     };
   } ./cargo-nextest-hook.sh;
 
@@ -106,9 +102,8 @@
 
     passthru.tests = {
       test = tests.rust-hooks.cargoSetupHook;
-    }
-    // lib.optionalAttrs (stdenv.hostPlatform.isLinux) {
-      testCross = pkgsCross.riscv64.tests.rust-hooks.cargoSetupHook;
+      ${if stdenv.hostPlatform.isLinux then "testCross" else null} =
+        pkgsCross.riscv64.tests.rust-hooks.cargoSetupHook;
     };
   } ./cargo-setup-hook.sh;