diff --git a/src/nix/show-derivation.cc b/src/nix/show-derivation.cc
index 8e1a58ac2..211e6a27a 100644
--- a/src/nix/show-derivation.cc
+++ b/src/nix/show-derivation.cc
@@ -103,7 +103,7 @@ struct CmdShowDerivation : InstallablesCommand
                 }
             }
 
-            drvObj.attr("platform", drv.platform);
+            drvObj.attr("system", drv.platform);
             drvObj.attr("builder", drv.builder);
 
             {