diff --git a/artiq/windows/run-test.nix b/artiq/windows/run-test.nix
index f775d95..063b23a 100644
--- a/artiq/windows/run-test.nix
+++ b/artiq/windows/run-test.nix
@@ -61,7 +61,7 @@ stdenv.mkDerivation {
     ${ssh "shutdown -s -t ${toString testTimeout}"}
 
     FAIL=n
-    ${ssh "anaconda\\scripts\\activate ${condaEnv} && ${testCommand}"} || FAIL=y
+    ( ${ssh "anaconda\\scripts\\activate ${condaEnv} && ${testCommand}"} ) || FAIL=y
 
     # Abort timeouted shutdown
     ${ssh "shutdown -a"}