diff --git a/src/nix/ls.cc b/src/nix/ls.cc
index 8566b8b06..5408c0929 100644
--- a/src/nix/ls.cc
+++ b/src/nix/ls.cc
@@ -76,7 +76,7 @@ struct MixLs : virtual Args, MixJSON
         if (path == "/") path = "";
 
         if (json) {
-            JSONPlaceholder jsonRoot(std::cout, true);
+            JSONPlaceholder jsonRoot(std::cout);
             listNar(jsonRoot, accessor, path);
         } else
             listText(accessor);
diff --git a/src/nix/path-info.cc b/src/nix/path-info.cc
index ca02a4c92..47caa401d 100644
--- a/src/nix/path-info.cc
+++ b/src/nix/path-info.cc
@@ -65,7 +65,7 @@ struct CmdPathInfo : StorePathsCommand, MixJSON
             pathLen = std::max(pathLen, storePath.size());
 
         if (json) {
-            JSONPlaceholder jsonRoot(std::cout, true);
+            JSONPlaceholder jsonRoot(std::cout);
             store->pathInfoToJSON(jsonRoot,
                 // FIXME: preserve order?
                 PathSet(storePaths.begin(), storePaths.end()),
diff --git a/src/nix/search.cc b/src/nix/search.cc
index f458367dc..a9dc2d6b9 100644
--- a/src/nix/search.cc
+++ b/src/nix/search.cc
@@ -84,7 +84,7 @@ struct CmdSearch : SourceExprCommand, MixJSON
 
         bool first = true;
 
-        auto jsonOut = json ? std::make_unique<JSONObject>(std::cout, true) : nullptr;
+        auto jsonOut = json ? std::make_unique<JSONObject>(std::cout) : nullptr;
 
         auto sToplevel = state->symbols.create("_toplevel");
         auto sRecurse = state->symbols.create("recurseForDerivations");
diff --git a/src/nix/show-config.cc b/src/nix/show-config.cc
index c628c2898..c64b12c8d 100644
--- a/src/nix/show-config.cc
+++ b/src/nix/show-config.cc
@@ -26,7 +26,7 @@ struct CmdShowConfig : Command, MixJSON
     {
         if (json) {
             // FIXME: use appropriate JSON types (bool, ints, etc).
-            JSONObject jsonObj(std::cout, true);
+            JSONObject jsonObj(std::cout);
             settings.toJSON(jsonObj);
         } else {
             for (auto & s : settings.getSettings())