diff --git a/Telegram/SourceFiles/base/lambda.h b/Telegram/SourceFiles/base/lambda.h
index 6bf720563..92955d0ca 100644
--- a/Telegram/SourceFiles/base/lambda.h
+++ b/Telegram/SourceFiles/base/lambda.h
@@ -576,49 +576,4 @@ inline lambda_internal::guard_t<PointersAndLambda...> lambda_guarded(PointersAnd
 	return lambda_internal::guard_t<PointersAndLambda...>(std::forward<PointersAndLambda>(qobjectsAndLambda)...);
 }
 
-// Pass lambda instead of a Qt void() slot.
-
-class lambda_slot_wrap : public QObject {
-	Q_OBJECT
-
-public:
-	lambda_slot_wrap(QObject *parent, lambda<void()> lambda) : QObject(parent), _lambda(std::move(lambda)) {
-	}
-
-public slots :
-	void action() {
-		_lambda();
-	}
-
-private:
-	lambda<void()> _lambda;
-
-};
-
-inline lambda_slot_wrap *lambda_slot(QObject *parent, lambda<void()> lambda) {
-	return new lambda_slot_wrap(parent, std::move(lambda));
-}
-
-class lambda_slot_once_wrap : public QObject {
-	Q_OBJECT
-
-public:
-	lambda_slot_once_wrap(QObject *parent, lambda_once<void()> lambda) : QObject(parent), _lambda(std::move(lambda)) {
-	}
-
-public slots :
-	void action() {
-		_lambda();
-		delete this;
-	}
-
-private:
-	lambda_once<void()> _lambda;
-
-};
-
-inline lambda_slot_once_wrap *lambda_slot_once(QObject *parent, lambda_once<void()> lambda) {
-	return new lambda_slot_once_wrap(parent, std::move(lambda));
-}
-
 } // namespace base
diff --git a/Telegram/SourceFiles/facades.cpp b/Telegram/SourceFiles/facades.cpp
index b470bba1d..8cc4df07a 100644
--- a/Telegram/SourceFiles/facades.cpp
+++ b/Telegram/SourceFiles/facades.cpp
@@ -41,7 +41,7 @@ namespace App {
 namespace internal {
 
 void CallDelayed(int duration, base::lambda_once<void()> &&lambda) {
-	QTimer::singleShot(duration, base::lambda_slot_once(App::app(), std::move(lambda)), SLOT(action()));
+	Messenger::Instance().callDelayed(duration, std::move(lambda));
 }
 
 } // namespace internal
diff --git a/Telegram/SourceFiles/messenger.h b/Telegram/SourceFiles/messenger.h
index 501c51231..de16d7e7a 100644
--- a/Telegram/SourceFiles/messenger.h
+++ b/Telegram/SourceFiles/messenger.h
@@ -22,6 +22,7 @@ Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
 
 #include "base/observer.h"
 #include "mtproto/auth_key.h"
+#include "base/timer.h"
 
 namespace App {
 void quit();
@@ -170,6 +171,10 @@ public:
 	void call_handleDelayedPeerUpdates();
 	void call_handleObservables();
 
+	void callDelayed(int duration, base::lambda_once<void()> &&lambda) {
+		_callDelayedTimer.call(duration, std::move(lambda));
+	}
+
 signals:
 	void peerPhotoDone(PeerId peer);
 	void peerPhotoFail(PeerId peer);
@@ -220,4 +225,6 @@ private:
 	QImage _logo;
 	QImage _logoNoMargin;
 
+	base::DelayedCallTimer _callDelayedTimer;
+
 };
diff --git a/Telegram/SourceFiles/platform/mac/main_window_mac.mm b/Telegram/SourceFiles/platform/mac/main_window_mac.mm
index fcf843b31..ea23b5557 100644
--- a/Telegram/SourceFiles/platform/mac/main_window_mac.mm
+++ b/Telegram/SourceFiles/platform/mac/main_window_mac.mm
@@ -407,10 +407,10 @@ void MainWindow::psFirstShow() {
 void MainWindow::createGlobalMenu() {
 	auto main = psMainMenu.addMenu(qsl("Telegram"));
 	auto about = main->addAction(lng_mac_menu_about_telegram(lt_telegram, qsl("Telegram")));
-	connect(about, SIGNAL(triggered()), base::lambda_slot(about, [] {
+	connect(about, &QAction::triggered, about, [] {
 		if (App::wnd() && App::wnd()->isHidden()) App::wnd()->showFromTray();
 		Ui::show(Box<AboutBox>());
-	}), SLOT(action()));
+	});
 	about->setMenuRole(QAction::AboutQtRole);
 
 	main->addSeparator();
@@ -433,12 +433,12 @@ void MainWindow::createGlobalMenu() {
 
 	QMenu *window = psMainMenu.addMenu(lang(lng_mac_menu_window));
 	psContacts = window->addAction(lang(lng_mac_menu_contacts));
-	connect(psContacts, SIGNAL(triggered()), base::lambda_slot(psContacts, [] {
+	connect(psContacts, &QAction::triggered, psContacts, [] {
 		if (App::wnd() && App::wnd()->isHidden()) App::wnd()->showFromTray();
 
 		if (!App::self()) return;
 		Ui::show(Box<ContactsBox>());
-	}), SLOT(action()));
+	});
 	psAddContact = window->addAction(lang(lng_mac_menu_add_contact), App::wnd(), SLOT(onShowAddContact()));
 	window->addSeparator();
 	psNewGroup = window->addAction(lang(lng_mac_menu_new_group), App::wnd(), SLOT(onShowNewGroup()));
diff --git a/Telegram/SourceFiles/ui/widgets/menu.cpp b/Telegram/SourceFiles/ui/widgets/menu.cpp
index 84e10b766..bf56cfc44 100644
--- a/Telegram/SourceFiles/ui/widgets/menu.cpp
+++ b/Telegram/SourceFiles/ui/widgets/menu.cpp
@@ -61,7 +61,7 @@ QAction *Menu::addAction(const QString &text, const QObject *receiver, const cha
 
 QAction *Menu::addAction(const QString &text, base::lambda<void()> callback, const style::icon *icon, const style::icon *iconOver) {
 	auto action = addAction(new QAction(text, this), icon, iconOver);
-	connect(action, SIGNAL(triggered(bool)), base::lambda_slot(action, std::move(callback)), SLOT(action()), Qt::QueuedConnection);
+	connect(action, &QAction::triggered, action, std::move(callback), Qt::QueuedConnection);
 	return action;
 }