diff --git a/libqpdf/NNTree.cc b/libqpdf/NNTree.cc
index 78098d6..f9ed69c 100644
--- a/libqpdf/NNTree.cc
+++ b/libqpdf/NNTree.cc
@@ -662,16 +662,15 @@ NNTreeImpl::compareKeyKid(QPDFObjectHandle const& key, Array const& kids, int id
 void
 NNTreeImpl::repair()
 {
-    auto new_node = QPDFObjectHandle::newDictionary();
-    new_node.replaceKey(itemsKey(), Array::empty());
+    auto new_node = Dictionary({{itemsKey(), Array::empty()}});
     NNTreeImpl repl(qpdf, new_node, key_type, value_valid, false);
     for (auto const& [key, value]: *this) {
         if (key && value) {
             repl.insert(key, value);
         }
     }
-    oh.replaceKey("/Kids", new_node.getKey("/Kids"));
-    oh.replaceKey(itemsKey(), new_node.getKey(itemsKey()));
+    oh.replaceKey("/Kids", new_node["/Kids"]);
+    oh.replaceKey(itemsKey(), new_node[itemsKey()]);
 }
 
 NNTreeImpl::iterator
@@ -757,10 +756,7 @@ NNTreeImpl::iterator
 NNTreeImpl::insertFirst(QPDFObjectHandle const& key, QPDFObjectHandle const& value)
 {
     auto iter = begin();
-    Array items;
-    if (iter.node.isDictionary()) {
-        items = iter.node.getKey(itemsKey());
-    }
+    Array items = iter.node[items_key];
     if (!items) {
         error(oh, "unable to find a valid items node");
     }
@@ -785,7 +781,7 @@ NNTreeImpl::insert(QPDFObjectHandle const& key, QPDFObjectHandle const& value)
     if (!iter.valid()) {
         return insertFirst(key, value);
     } else if (compareKeys(key, iter->first) == 0) {
-        Array items = iter.node.getKey(itemsKey());
+        Array items = iter.node[itemsKey()];
         items.set(iter.item_number + 1, value);
         iter.updateIValue();
     } else {
diff --git a/libqpdf/qpdf/NNTree.hh b/libqpdf/qpdf/NNTree.hh
index f3633ad..a967624 100644
--- a/libqpdf/qpdf/NNTree.hh
+++ b/libqpdf/qpdf/NNTree.hh
@@ -128,12 +128,12 @@ class NNTreeImpl final
 
     NNTreeImpl(
         QPDF& qpdf,
-        QPDFObjectHandle& oh,
+        QPDFObjectHandle oh,
         qpdf_object_type_e key_type,
         std::function<bool(QPDFObjectHandle const&)> value_validator,
         bool auto_repair) :
         qpdf(qpdf),
-        oh(oh),
+        oh(std::move(oh)),
         key_type(key_type),
         items_key(key_type == ::ot_string ? "/Names" : "/Nums"),
         value_valid(value_validator),