diff --git a/gtk/.clang-tidy b/gtk/.clang-tidy
index 2ba6e103f..82148826f 100644
--- a/gtk/.clang-tidy
+++ b/gtk/.clang-tidy
@@ -7,6 +7,7 @@ Checks: >
   -cppcoreguidelines-narrowing-conversions,
   modernize-*,
   -modernize-use-trailing-return-type,
+  performance-*,
   readability-*,
   -readability-function-cognitive-complexity,
   -readability-identifier-length,
diff --git a/gtk/Actions.cc b/gtk/Actions.cc
index 33caaca7a..da3b1aff8 100644
--- a/gtk/Actions.cc
+++ b/gtk/Actions.cc
@@ -112,7 +112,7 @@ Glib::RefPtr<Gio::SimpleActionGroup> gtr_actions_init(Glib::RefPtr<Gtk::Builder>
 {
     myBuilder = builder.get();
 
-    auto const action_group = Gio::SimpleActionGroup::create();
+    auto action_group = Gio::SimpleActionGroup::create();
 
     auto const match = gtr_pref_string_get(TR_KEY_sort_mode);
 
diff --git a/gtk/FilterBar.cc b/gtk/FilterBar.cc
index b912bb2e4..daa7a9024 100644
--- a/gtk/FilterBar.cc
+++ b/gtk/FilterBar.cc
@@ -288,7 +288,7 @@ bool tracker_filter_model_update(Glib::RefPtr<Gtk::TreeStore> const& tracker_mod
 
 Glib::RefPtr<Gtk::TreeStore> tracker_filter_model_new(Glib::RefPtr<Gtk::TreeModel> const& tmodel)
 {
-    auto const store = Gtk::TreeStore::create(tracker_filter_cols);
+    auto store = Gtk::TreeStore::create(tracker_filter_cols);
 
     auto iter = store->append();
     iter->set_value(tracker_filter_cols.displayname, Glib::ustring(_("All")));
@@ -531,7 +531,7 @@ Glib::RefPtr<Gtk::ListStore> activity_filter_model_new(Glib::RefPtr<Gtk::TreeMod
         { ACTIVITY_FILTER_ERROR, nullptr, N_("Error"), "dialog-error" },
     } });
 
-    auto const store = Gtk::ListStore::create(activity_filter_cols);
+    auto store = Gtk::ListStore::create(activity_filter_cols);
 
     for (auto const& type : types)
     {
diff --git a/gtk/PrefsDialog.cc b/gtk/PrefsDialog.cc
index 5117f1d5c..679692d1d 100644
--- a/gtk/PrefsDialog.cc
+++ b/gtk/PrefsDialog.cc
@@ -686,7 +686,7 @@ RemotePage::WhitelistModelColumns const RemotePage::whitelist_cols;
 
 Glib::RefPtr<Gtk::ListStore> RemotePage::whitelist_tree_model_new(std::string const& whitelist)
 {
-    auto const store = Gtk::ListStore::create(whitelist_cols);
+    auto store = Gtk::ListStore::create(whitelist_cols);
 
     std::istringstream stream(whitelist);
     std::string s;
diff --git a/gtk/Session.cc b/gtk/Session.cc
index ad7ae9b38..3053cd76a 100644
--- a/gtk/Session.cc
+++ b/gtk/Session.cc
@@ -42,18 +42,21 @@ using namespace std::literals;
 namespace
 {
 
-using TrVariantPtr = std::shared_ptr<tr_variant>;
-
-TrVariantPtr create_variant(tr_variant&& other)
+class TrVariantDeleter
 {
-    auto result = TrVariantPtr(
-        new tr_variant{},
-        [](tr_variant* ptr)
-        {
-            tr_variantClear(ptr);
-            std::default_delete<tr_variant>()(ptr);
-        });
-    *result = std::move(other);
+public:
+    void operator()(tr_variant* ptr) const
+    {
+        tr_variantClear(ptr);
+        std::default_delete<tr_variant>()(ptr);
+    }
+};
+
+using TrVariantPtr = std::unique_ptr<tr_variant, TrVariantDeleter>;
+
+TrVariantPtr create_variant(tr_variant& other)
+{
+    auto result = TrVariantPtr(new tr_variant(other));
     tr_variantInitBool(&other, false);
     return result;
 }
@@ -105,7 +108,7 @@ public:
     void add_torrent(tr_torrent* tor, bool do_notify);
     bool add_from_url(Glib::ustring const& url);
 
-    void send_rpc_request(tr_variant const* request, int64_t tag, std::function<void(tr_variant*)> const& response_func);
+    void send_rpc_request(tr_variant const* request, int64_t tag, std::function<void(tr_variant&)> const& response_func);
 
     void commit_prefs_change(tr_quark key);
 
@@ -1556,17 +1559,17 @@ namespace
 
 int64_t nextTag = 1;
 
-std::map<int64_t, std::function<void(tr_variant*)>> pendingRequests;
+std::map<int64_t, std::function<void(tr_variant&)>> pendingRequests;
 
-bool core_read_rpc_response_idle(TrVariantPtr const& response)
+bool core_read_rpc_response_idle(tr_variant& response)
 {
-    if (int64_t tag = 0; tr_variantDictFindInt(response.get(), TR_KEY_tag, &tag))
+    if (int64_t tag = 0; tr_variantDictFindInt(&response, TR_KEY_tag, &tag))
     {
         if (auto const data_it = pendingRequests.find(tag); data_it != pendingRequests.end())
         {
             if (auto const& response_func = data_it->second; response_func)
             {
-                response_func(response.get());
+                response_func(response);
             }
 
             pendingRequests.erase(data_it);
@@ -1582,8 +1585,8 @@ bool core_read_rpc_response_idle(TrVariantPtr const& response)
 
 void core_read_rpc_response(tr_session* /*session*/, tr_variant* response, gpointer /*user_data*/)
 {
-    Glib::signal_idle().connect([response_copy = create_variant(std::move(*response))]() mutable
-                                { return core_read_rpc_response_idle(response_copy); });
+    Glib::signal_idle().connect([owned_response = std::shared_ptr(create_variant(*response))]() mutable
+                                { return core_read_rpc_response_idle(*owned_response); });
 }
 
 } // namespace
@@ -1591,7 +1594,7 @@ void core_read_rpc_response(tr_session* /*session*/, tr_variant* response, gpoin
 void Session::Impl::send_rpc_request(
     tr_variant const* request,
     int64_t tag,
-    std::function<void(tr_variant*)> const& response_func)
+    std::function<void(tr_variant&)> const& response_func)
 {
     if (session_ == nullptr)
     {
@@ -1627,12 +1630,12 @@ void Session::port_test()
     impl_->send_rpc_request(
         &request,
         tag,
-        [this](auto* response)
+        [this](auto& response)
         {
             tr_variant* args = nullptr;
             bool is_open = false;
 
-            if (!tr_variantDictFindDict(response, TR_KEY_arguments, &args) ||
+            if (!tr_variantDictFindDict(&response, TR_KEY_arguments, &args) ||
                 !tr_variantDictFindBool(args, TR_KEY_port_is_open, &is_open))
             {
                 is_open = false;
@@ -1659,12 +1662,12 @@ void Session::blocklist_update()
     impl_->send_rpc_request(
         &request,
         tag,
-        [this](auto* response)
+        [this](auto& response)
         {
             tr_variant* args = nullptr;
             int64_t ruleCount = 0;
 
-            if (!tr_variantDictFindDict(response, TR_KEY_arguments, &args) ||
+            if (!tr_variantDictFindDict(&response, TR_KEY_arguments, &args) ||
                 !tr_variantDictFindInt(args, TR_KEY_blocklist_size, &ruleCount))
             {
                 ruleCount = -1;