diff --git a/sinara-systems.nix b/sinara-systems.nix
index 6eb90d6..70eca86 100644
--- a/sinara-systems.nix
+++ b/sinara-systems.nix
@@ -44,7 +44,7 @@ let
           target = "sayma";
           variant = "satellite";
           buildCommand = "python -m artiq.gateware.targets.sayma_rtm && python -m artiq.gateware.targets.sayma_amc -V satellite";
-          extraInstallCommands = "cp artiq_sayma/rtm_gateware/rtm.bit $TARGET_DIR";
+          extraInstallCommands = "cp artiq_sayma/rtm_gateware/rtm.bit \$TARGET_DIR";
         };
       }
     EOF