diff --git a/doc/api_break.dox b/doc/api_break.dox
index 1fb5b53c42b..3b709f16f23 100644
--- a/doc/api_break.dox
+++ b/doc/api_break.dox
@@ -603,13 +603,17 @@ QgsCptCityColorRampDialog        {#qgis_api_break_3_0_QgsCptCityColorRampDialog}
 and the new ramp can be retrieved after executing the dialog by calling ramp().
 - Some internal methods which were previously public or protected were made private.
 
+QgsCptCityDataItem        {#qgis_api_break_3_0_QgsCptCityDataItem}
+-----------------------
+
+- emitBeginInsertItems, emitEndInsertItems, emitBeginRemoveItems and emitEndRemoveItems were removed. There
+should be no need to call these slots manually.
 
 QgsCptCitySelectionItem        {#qgis_api_break_3_0_QgsCptCitySelectionItem}
 -----------------------
 
 - parseXML() has been renamed to parseXml()
 
-
 QgsCRSCache        {#qgis_api_break_3_0_QgsCRSCache}
 -----------
 
diff --git a/python/core/symbology-ng/qgscptcityarchive.sip b/python/core/symbology-ng/qgscptcityarchive.sip
index 9453acc425a..ab758d032ac 100644
--- a/python/core/symbology-ng/qgscptcityarchive.sip
+++ b/python/core/symbology-ng/qgscptcityarchive.sip
@@ -129,12 +129,6 @@ class QgsCptCityDataItem : QObject
 
     bool isValid();
 
-  public slots:
-    void emitBeginInsertItems( QgsCptCityDataItem* parent, int first, int last );
-    void emitEndInsertItems();
-    void emitBeginRemoveItems( QgsCptCityDataItem* parent, int first, int last );
-    void emitEndRemoveItems();
-
   signals:
     void beginInsertItems( QgsCptCityDataItem* parent, int first, int last );
     void endInsertItems();
diff --git a/src/app/qgisapp.cpp b/src/app/qgisapp.cpp
index f12eed934a7..e932c78e186 100644
--- a/src/app/qgisapp.cpp
+++ b/src/app/qgisapp.cpp
@@ -10249,7 +10249,7 @@ void QgisApp::layersWereAdded( const QList<QgsMapLayer *>& theLayers )
       connect( rlayer, SIGNAL( drawingProgress( int, int ) ), this, SLOT( showProgress( int, int ) ) );
 
       // connect up any request the raster may make to update the statusbar message
-      connect( rlayer, SIGNAL( statusChanged( QString ) ), this, SLOT( showStatusMessage( QString ) ) );
+      connect( rlayer, &QgsRasterLayer::statusChanged, this, &QgisApp::showStatusMessage );
 
       provider = rlayer->dataProvider();
     }
diff --git a/src/core/layertree/qgslayertreemodel.cpp b/src/core/layertree/qgslayertreemodel.cpp
index 2fc0cf86be0..27079883e65 100644
--- a/src/core/layertree/qgslayertreemodel.cpp
+++ b/src/core/layertree/qgslayertreemodel.cpp
@@ -837,7 +837,7 @@ void QgsLayerTreeModel::connectToLayer( QgsLayerTreeLayer* nodeLayer )
   }
 
   QgsMapLayer* layer = nodeLayer->layer();
-  connect( layer, SIGNAL( legendChanged() ), this, SLOT( layerLegendChanged() ), Qt::UniqueConnection );
+  connect( layer, &QgsMapLayer::legendChanged, this, &QgsLayerTreeModel::layerLegendChanged, Qt::UniqueConnection );
 
   if ( layer->type() == QgsMapLayer::VectorLayer )
   {
diff --git a/src/core/qgsmaplayer.cpp b/src/core/qgsmaplayer.cpp
index 31fde2814f9..00dee9bd355 100644
--- a/src/core/qgsmaplayer.cpp
+++ b/src/core/qgsmaplayer.cpp
@@ -1649,7 +1649,7 @@ void QgsMapLayer::setLegend( QgsMapLayerLegend* legend )
   mLegend = legend;
 
   if ( mLegend )
-    connect( mLegend, SIGNAL( itemsChanged() ), this, SIGNAL( legendChanged() ) );
+    connect( mLegend, &QgsMapLayerLegend::itemsChanged, this, &QgsMapLayer::legendChanged );
 
   emit legendChanged();
 }
diff --git a/src/core/qgstransactiongroup.cpp b/src/core/qgstransactiongroup.cpp
index 94ae4700f81..486c9fc8e01 100644
--- a/src/core/qgstransactiongroup.cpp
+++ b/src/core/qgstransactiongroup.cpp
@@ -53,8 +53,8 @@ bool QgsTransactionGroup::addLayer( QgsVectorLayer* layer )
 
   mLayers.insert( layer );
 
-  connect( layer, SIGNAL( beforeEditingStarted() ), this, SLOT( onEditingStarted() ) );
-  connect( layer, SIGNAL( destroyed() ), this, SLOT( onLayerDeleted() ) );
+  connect( layer, &QgsVectorLayer::beforeEditingStarted, this, &QgsTransactionGroup::onEditingStarted );
+  connect( layer, &QgsVectorLayer::destroyed, this, &QgsTransactionGroup::onLayerDeleted );
 
   return true;
 }
@@ -88,8 +88,8 @@ void QgsTransactionGroup::onEditingStarted()
   {
     mTransaction->addLayer( layer );
     layer->startEditing();
-    connect( layer, SIGNAL( beforeCommitChanges() ), this, SLOT( onCommitChanges() ) );
-    connect( layer, SIGNAL( beforeRollBack() ), this, SLOT( onRollback() ) );
+    connect( layer, &QgsVectorLayer::beforeCommitChanges, this, &QgsTransactionGroup::onCommitChanges );
+    connect( layer, &QgsVectorLayer::beforeRollBack, this, &QgsTransactionGroup::onRollback );
   }
 }
 
@@ -160,8 +160,8 @@ void QgsTransactionGroup::disableTransaction()
 
   Q_FOREACH ( QgsVectorLayer* layer, mLayers )
   {
-    disconnect( layer, SIGNAL( beforeCommitChanges() ), this, SLOT( onCommitChanges() ) );
-    disconnect( layer, SIGNAL( beforeRollBack() ), this, SLOT( onRollback() ) );
+    disconnect( layer, &QgsVectorLayer::beforeCommitChanges, this, &QgsTransactionGroup::onCommitChanges );
+    disconnect( layer, &QgsVectorLayer::beforeRollBack, this, &QgsTransactionGroup::onRollback );
   }
 }
 
diff --git a/src/core/qgsvectorlayer.cpp b/src/core/qgsvectorlayer.cpp
index 8c0782feb4d..a020a4409d3 100644
--- a/src/core/qgsvectorlayer.cpp
+++ b/src/core/qgsvectorlayer.cpp
@@ -157,7 +157,7 @@ QgsVectorLayer::QgsVectorLayer( const QString& vectorLayerPath,
 
   connect( this, SIGNAL( selectionChanged( QgsFeatureIds, QgsFeatureIds, bool ) ), this, SIGNAL( selectionChanged() ) );
   connect( this, SIGNAL( selectionChanged( QgsFeatureIds, QgsFeatureIds, bool ) ), this, SIGNAL( repaintRequested() ) );
-  connect( QgsProject::instance()->relationManager(), SIGNAL( relationsLoaded() ), this, SLOT( onRelationsLoaded() ) );
+  connect( QgsProject::instance()->relationManager(), &QgsRelationManager::relationsLoaded, this, &QgsVectorLayer::onRelationsLoaded );
 
   // Default simplify drawing settings
   QSettings settings;
@@ -1329,30 +1329,21 @@ bool QgsVectorLayer::startEditing()
     mEditBuffer = new QgsVectorLayerEditBuffer( this );
   }
   // forward signals
-  connect( mEditBuffer, SIGNAL( layerModified() ), this, SLOT( invalidateSymbolCountedFlag() ) );
-  connect( mEditBuffer, SIGNAL( layerModified() ), this, SIGNAL( layerModified() ) ); // TODO[MD]: necessary?
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::layerModified, this, &QgsVectorLayer::invalidateSymbolCountedFlag );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::layerModified, this, &QgsVectorLayer::layerModified ); // TODO[MD]: necessary?
   //connect( mEditBuffer, SIGNAL( layerModified() ), this, SLOT( triggerRepaint() ) ); // TODO[MD]: works well?
-  connect( mEditBuffer, SIGNAL( featureAdded( QgsFeatureId ) ), this, SIGNAL( featureAdded( QgsFeatureId ) ) );
-  connect( mEditBuffer, SIGNAL( featureDeleted( QgsFeatureId ) ), this, SLOT( onFeatureDeleted( QgsFeatureId ) ) );
-  connect( mEditBuffer, SIGNAL( geometryChanged( QgsFeatureId, const QgsGeometry& ) ), this, SIGNAL( geometryChanged( QgsFeatureId, const QgsGeometry& ) ) );
-  connect( mEditBuffer, SIGNAL( attributeValueChanged( QgsFeatureId, int, QVariant ) ), this, SIGNAL( attributeValueChanged( QgsFeatureId, int, QVariant ) ) );
-  connect( mEditBuffer, SIGNAL( attributeAdded( int ) ), this, SIGNAL( attributeAdded( int ) ) );
-  connect( mEditBuffer, SIGNAL( attributeDeleted( int ) ), this, SIGNAL( attributeDeleted( int ) ) );
-
-  connect( mEditBuffer, SIGNAL( committedAttributesDeleted( const QString &, const QgsAttributeList & ) ),
-           this, SIGNAL( committedAttributesDeleted( const QString &, const QgsAttributeList & ) ) );
-
-  connect( mEditBuffer, SIGNAL( committedAttributesAdded( const QString &, const QList<QgsField> & ) ),
-           this, SIGNAL( committedAttributesAdded( const QString &, const QList<QgsField> & ) ) );
-
-  connect( mEditBuffer, SIGNAL( committedFeaturesAdded( QString, QgsFeatureList ) ), this, SIGNAL( committedFeaturesAdded( QString, QgsFeatureList ) ) );
-  connect( mEditBuffer, SIGNAL( committedFeaturesRemoved( QString, QgsFeatureIds ) ), this, SIGNAL( committedFeaturesRemoved( QString, QgsFeatureIds ) ) );
-
-  connect( mEditBuffer, SIGNAL( committedAttributeValuesChanges( const QString &, const QgsChangedAttributesMap & ) ),
-           this, SIGNAL( committedAttributeValuesChanges( const QString &, const QgsChangedAttributesMap & ) ) );
-
-  connect( mEditBuffer, SIGNAL( committedGeometriesChanges( const QString &, const QgsGeometryMap & ) ),
-           this, SIGNAL( committedGeometriesChanges( const QString &, const QgsGeometryMap & ) ) );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::featureAdded, this, &QgsVectorLayer::featureAdded );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::featureDeleted, this, &QgsVectorLayer::onFeatureDeleted );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::geometryChanged, this, &QgsVectorLayer::geometryChanged );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::attributeValueChanged, this, &QgsVectorLayer::attributeValueChanged );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::attributeAdded, this, &QgsVectorLayer::attributeAdded );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::attributeDeleted, this, &QgsVectorLayer::attributeDeleted );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::committedAttributesDeleted, this, &QgsVectorLayer::committedAttributesDeleted );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::committedAttributesAdded, this, &QgsVectorLayer::committedAttributesAdded );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::committedFeaturesAdded, this, &QgsVectorLayer::committedFeaturesAdded );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::committedFeaturesRemoved, this, &QgsVectorLayer::committedFeaturesRemoved );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::committedAttributeValuesChanges, this, &QgsVectorLayer::committedAttributeValuesChanges );
+  connect( mEditBuffer, &QgsVectorLayerEditBuffer::committedGeometriesChanges, this, &QgsVectorLayer::committedGeometriesChanges );
 
   updateFields();
 
@@ -1416,7 +1407,7 @@ bool QgsVectorLayer::readXml( const QDomNode& layer_node )
   if ( !mJoinBuffer )
   {
     mJoinBuffer = new QgsVectorLayerJoinBuffer( this );
-    connect( mJoinBuffer, SIGNAL( joinedFieldsChanged() ), this, SLOT( onJoinedFieldsChanged() ) );
+    connect( mJoinBuffer, &QgsVectorLayerJoinBuffer::joinedFieldsChanged, this, &QgsVectorLayer::onJoinedFieldsChanged );
   }
   mJoinBuffer->readXml( layer_node );
 
@@ -1525,7 +1516,7 @@ bool QgsVectorLayer::setDataProvider( QString const & provider )
     return false;
   }
 
-  connect( mDataProvider, SIGNAL( raiseError( QString ) ), this, SIGNAL( raiseError( QString ) ) );
+  connect( mDataProvider, &QgsVectorDataProvider::raiseError, this, &QgsVectorLayer::raiseError );
 
   QgsDebugMsg( "Instantiated the data provider plugin" );
 
@@ -1537,13 +1528,13 @@ bool QgsVectorLayer::setDataProvider( QString const & provider )
   }
 
   // TODO: Check if the provider has the capability to send fullExtentCalculated
-  connect( mDataProvider, SIGNAL( fullExtentCalculated() ), this, SLOT( updateExtents() ) );
+  connect( mDataProvider, &QgsVectorDataProvider::fullExtentCalculated, this, &QgsVectorLayer::updateExtents );
 
   // get and store the feature type
   mWkbType = mDataProvider->wkbType();
 
   mJoinBuffer = new QgsVectorLayerJoinBuffer( this );
-  connect( mJoinBuffer, SIGNAL( joinedFieldsChanged() ), this, SLOT( onJoinedFieldsChanged() ) );
+  connect( mJoinBuffer, &QgsVectorLayerJoinBuffer::joinedFieldsChanged, this, &QgsVectorLayer::onJoinedFieldsChanged );
   mExpressionFieldBuffer = new QgsExpressionFieldBuffer();
   updateFields();
 
@@ -4165,11 +4156,11 @@ bool QgsVectorLayer::setDependencies( const QSet<QgsMapLayerDependency>& oDeps )
     QgsVectorLayer* lyr = static_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( dep.layerId() ) );
     if ( lyr == nullptr )
       continue;
-    disconnect( lyr, SIGNAL( featureAdded( QgsFeatureId ) ), this, SIGNAL( dataChanged() ) );
-    disconnect( lyr, SIGNAL( featureDeleted( QgsFeatureId ) ), this, SIGNAL( dataChanged() ) );
-    disconnect( lyr, SIGNAL( geometryChanged( QgsFeatureId, const QgsGeometry& ) ), this, SIGNAL( dataChanged() ) );
-    disconnect( lyr, SIGNAL( dataChanged() ), this, SIGNAL( dataChanged() ) );
-    disconnect( lyr, SIGNAL( repaintRequested() ), this, SLOT( triggerRepaint() ) );
+    disconnect( lyr, &QgsVectorLayer::featureAdded, this, &QgsVectorLayer::dataChanged );
+    disconnect( lyr, &QgsVectorLayer::featureDeleted, this, &QgsVectorLayer::dataChanged );
+    disconnect( lyr, &QgsVectorLayer::geometryChanged, this, &QgsVectorLayer::dataChanged );
+    disconnect( lyr, &QgsVectorLayer::dataChanged, this, &QgsVectorLayer::dataChanged );
+    disconnect( lyr, &QgsVectorLayer::repaintRequested, this, &QgsVectorLayer::triggerRepaint );
   }
 
   // assign new dependencies
@@ -4185,11 +4176,11 @@ bool QgsVectorLayer::setDependencies( const QSet<QgsMapLayerDependency>& oDeps )
     QgsVectorLayer* lyr = static_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( dep.layerId() ) );
     if ( lyr == nullptr )
       continue;
-    connect( lyr, SIGNAL( featureAdded( QgsFeatureId ) ), this, SIGNAL( dataChanged() ) );
-    connect( lyr, SIGNAL( featureDeleted( QgsFeatureId ) ), this, SIGNAL( dataChanged() ) );
-    connect( lyr, SIGNAL( geometryChanged( QgsFeatureId, const QgsGeometry& ) ), this, SIGNAL( dataChanged() ) );
-    connect( lyr, SIGNAL( dataChanged() ), this, SIGNAL( dataChanged() ) );
-    connect( lyr, SIGNAL( repaintRequested() ), this, SLOT( triggerRepaint() ) );
+    connect( lyr, &QgsVectorLayer::featureAdded, this, &QgsVectorLayer::dataChanged );
+    connect( lyr, &QgsVectorLayer::featureDeleted, this, &QgsVectorLayer::dataChanged );
+    connect( lyr, &QgsVectorLayer::geometryChanged, this, &QgsVectorLayer::dataChanged );
+    connect( lyr, &QgsVectorLayer::dataChanged, this, &QgsVectorLayer::dataChanged );
+    connect( lyr, &QgsVectorLayer::repaintRequested, this, &QgsVectorLayer::triggerRepaint );
   }
 
   // if new layers are present, emit a data change
diff --git a/src/core/qgsvectorlayercache.cpp b/src/core/qgsvectorlayercache.cpp
index c46cb8e899c..74a8ef7c6cd 100644
--- a/src/core/qgsvectorlayercache.cpp
+++ b/src/core/qgsvectorlayercache.cpp
@@ -26,18 +26,18 @@ QgsVectorLayerCache::QgsVectorLayerCache( QgsVectorLayer* layer, int cacheSize,
 {
   mCache.setMaxCost( cacheSize );
 
-  connect( mLayer, SIGNAL( featureDeleted( QgsFeatureId ) ), SLOT( featureDeleted( QgsFeatureId ) ) );
-  connect( mLayer, SIGNAL( featureAdded( QgsFeatureId ) ), SLOT( onFeatureAdded( QgsFeatureId ) ) );
-  connect( mLayer, SIGNAL( destroyed() ), SLOT( layerDeleted() ) );
+  connect( mLayer, &QgsVectorLayer::featureDeleted, this, &QgsVectorLayerCache::featureDeleted );
+  connect( mLayer, &QgsVectorLayer::featureAdded, this, &QgsVectorLayerCache::onFeatureAdded );
+  connect( mLayer, &QgsVectorLayer::destroyed, this, &QgsVectorLayerCache::layerDeleted );
 
   setCacheGeometry( true );
   setCacheSubsetOfAttributes( mLayer->attributeList() );
   setCacheAddedAttributes( true );
 
-  connect( mLayer, SIGNAL( attributeDeleted( int ) ), SLOT( attributeDeleted( int ) ) );
-  connect( mLayer, SIGNAL( updatedFields() ), SLOT( invalidate() ) );
-  connect( mLayer, SIGNAL( dataChanged() ), SLOT( invalidate() ) );
-  connect( mLayer, SIGNAL( attributeValueChanged( QgsFeatureId, int, const QVariant& ) ), SLOT( onAttributeValueChanged( QgsFeatureId, int, const QVariant& ) ) );
+  connect( mLayer, &QgsVectorLayer::attributeDeleted, this, &QgsVectorLayerCache::attributeDeleted );
+  connect( mLayer, &QgsVectorLayer::updatedFields, this, &QgsVectorLayerCache::invalidate );
+  connect( mLayer, &QgsVectorLayer::dataChanged, this, &QgsVectorLayerCache::invalidate );
+  connect( mLayer, &QgsVectorLayer::attributeValueChanged, this, &QgsVectorLayerCache::onAttributeValueChanged );
 }
 
 QgsVectorLayerCache::~QgsVectorLayerCache()
@@ -61,11 +61,11 @@ void QgsVectorLayerCache::setCacheGeometry( bool cacheGeometry )
   mCacheGeometry = cacheGeometry && mLayer->hasGeometryType();
   if ( cacheGeometry )
   {
-    connect( mLayer, SIGNAL( geometryChanged( QgsFeatureId, const QgsGeometry& ) ), SLOT( geometryChanged( QgsFeatureId, const QgsGeometry& ) ) );
+    connect( mLayer, &QgsVectorLayer::geometryChanged, this, &QgsVectorLayerCache::geometryChanged );
   }
   else
   {
-    disconnect( mLayer, SIGNAL( geometryChanged( QgsFeatureId, const QgsGeometry& ) ), this, SLOT( geometryChanged( QgsFeatureId, const QgsGeometry& ) ) );
+    disconnect( mLayer, &QgsVectorLayer::geometryChanged, this, &QgsVectorLayerCache::geometryChanged );
   }
 }
 
@@ -124,11 +124,11 @@ void QgsVectorLayerCache::setCacheAddedAttributes( bool cacheAddedAttributes )
 {
   if ( cacheAddedAttributes )
   {
-    connect( mLayer, SIGNAL( attributeAdded( int ) ), SLOT( attributeAdded( int ) ) );
+    connect( mLayer, &QgsVectorLayer::attributeAdded, this, &QgsVectorLayerCache::attributeAdded );
   }
   else
   {
-    disconnect( mLayer, SIGNAL( attributeAdded( int ) ), this, SLOT( attributeAdded( int ) ) );
+    disconnect( mLayer, &QgsVectorLayer::attributeAdded, this, &QgsVectorLayerCache::attributeAdded );
   }
 }
 
diff --git a/src/core/qgsvectorlayereditbuffer.cpp b/src/core/qgsvectorlayereditbuffer.cpp
index 72c9fb8072a..7ff4a097324 100644
--- a/src/core/qgsvectorlayereditbuffer.cpp
+++ b/src/core/qgsvectorlayereditbuffer.cpp
@@ -37,7 +37,7 @@ template <class Key, class T> void mapToReversedLists( const QMap< Key, T >& map
 QgsVectorLayerEditBuffer::QgsVectorLayerEditBuffer( QgsVectorLayer* layer )
     : L( layer )
 {
-  connect( L->undoStack(), SIGNAL( indexChanged( int ) ), this, SLOT( undoIndexChanged( int ) ) ); // TODO[MD]: queued?
+  connect( L->undoStack(), &QUndoStack::indexChanged, this, &QgsVectorLayerEditBuffer::undoIndexChanged ); // TODO[MD]: queued?
 }
 
 QgsVectorLayerEditBuffer::~QgsVectorLayerEditBuffer()
diff --git a/src/core/qgsvectorlayerjoinbuffer.cpp b/src/core/qgsvectorlayerjoinbuffer.cpp
index e9b734493e8..c69d7ede161 100644
--- a/src/core/qgsvectorlayerjoinbuffer.cpp
+++ b/src/core/qgsvectorlayerjoinbuffer.cpp
@@ -89,8 +89,8 @@ bool QgsVectorLayerJoinBuffer::addJoin( const QgsVectorJoinInfo& joinInfo )
   // Unique connection makes sure we do not respond to one layer's update more times (in case of multiple join)
   if ( QgsVectorLayer* vl = qobject_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( joinInfo.joinLayerId ) ) )
   {
-    connect( vl, SIGNAL( updatedFields() ), this, SLOT( joinedLayerUpdatedFields() ), Qt::UniqueConnection );
-    connect( vl, SIGNAL( layerModified() ), this, SLOT( joinedLayerModified() ), Qt::UniqueConnection );
+    connect( vl, &QgsVectorLayer::updatedFields, this, &QgsVectorLayerJoinBuffer::joinedLayerUpdatedFields, Qt::UniqueConnection );
+    connect( vl, &QgsVectorLayer::layerModified, this, &QgsVectorLayerJoinBuffer::joinedLayerModified, Qt::UniqueConnection );
   }
 
   emit joinedFieldsChanged();
@@ -113,7 +113,7 @@ bool QgsVectorLayerJoinBuffer::removeJoin( const QString& joinLayerId )
 
   if ( QgsVectorLayer* vl = qobject_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( joinLayerId ) ) )
   {
-    disconnect( vl, SIGNAL( updatedFields() ), this, SLOT( joinedLayerUpdatedFields() ) );
+    disconnect( vl, &QgsVectorLayer::updatedFields, this, &QgsVectorLayerJoinBuffer::joinedLayerUpdatedFields );
   }
 
   emit joinedFieldsChanged();
@@ -273,8 +273,8 @@ void QgsVectorLayerJoinBuffer::createJoinCaches()
     // make sure we are connected to the joined layer
     if ( QgsVectorLayer* vl = qobject_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( joinIt->joinLayerId ) ) )
     {
-      connect( vl, SIGNAL( updatedFields() ), this, SLOT( joinedLayerUpdatedFields() ), Qt::UniqueConnection );
-      connect( vl, SIGNAL( layerModified() ), this, SLOT( joinedLayerModified() ), Qt::UniqueConnection );
+      connect( vl, &QgsVectorLayer::updatedFields, this, &QgsVectorLayerJoinBuffer::joinedLayerUpdatedFields, Qt::UniqueConnection );
+      connect( vl, &QgsVectorLayer::layerModified, this, &QgsVectorLayerJoinBuffer::joinedLayerModified, Qt::UniqueConnection );
     }
   }
 }
diff --git a/src/core/raster/qgsrasterlayer.cpp b/src/core/raster/qgsrasterlayer.cpp
index 4260760814f..febade81ce4 100644
--- a/src/core/raster/qgsrasterlayer.cpp
+++ b/src/core/raster/qgsrasterlayer.cpp
@@ -818,16 +818,10 @@ void QgsRasterLayer::setDataProvider( QString const & provider )
   mLastModified = lastModified( mDataSource );
 
   // Connect provider signals
-  connect(
-    mDataProvider, SIGNAL( progress( int, double, QString ) ),
-    this,          SLOT( onProgress( int, double, QString ) )
-  );
+  connect( mDataProvider, &QgsRasterDataProvider::progress, this, &QgsRasterLayer::onProgress );
 
   // Do a passthrough for the status bar text
-  connect(
-    mDataProvider, SIGNAL( statusChanged( QString ) ),
-    this,          SIGNAL( statusChanged( QString ) )
-  );
+  connect( mDataProvider, &QgsRasterDataProvider::statusChanged, this, &QgsRasterLayer::statusChanged );
 
   //mark the layer as valid
   mValid = true;
diff --git a/src/core/symbology-ng/qgscptcityarchive.cpp b/src/core/symbology-ng/qgscptcityarchive.cpp
index 4d90e47dcf4..342bccd4715 100644
--- a/src/core/symbology-ng/qgscptcityarchive.cpp
+++ b/src/core/symbology-ng/qgscptcityarchive.cpp
@@ -508,23 +508,6 @@ QgsCptCityDataItem::~QgsCptCityDataItem()
   // QgsDebugMsg( "mName = " + mName + " mPath = " + mPath );
 }
 
-void QgsCptCityDataItem::emitBeginInsertItems( QgsCptCityDataItem* parent, int first, int last )
-{
-  emit beginInsertItems( parent, first, last );
-}
-void QgsCptCityDataItem::emitEndInsertItems()
-{
-  emit endInsertItems();
-}
-void QgsCptCityDataItem::emitBeginRemoveItems( QgsCptCityDataItem* parent, int first, int last )
-{
-  emit beginRemoveItems( parent, first, last );
-}
-void QgsCptCityDataItem::emitEndRemoveItems()
-{
-  emit endRemoveItems();
-}
-
 QVector<QgsCptCityDataItem*> QgsCptCityDataItem::createChildren()
 {
   QVector<QgsCptCityDataItem*> children;
@@ -607,14 +590,10 @@ void QgsCptCityDataItem::addChildItem( QgsCptCityDataItem * child, bool refresh
 
   mChildren.insert( i, child );
 
-  connect( child, SIGNAL( beginInsertItems( QgsCptCityDataItem*, int, int ) ),
-           this, SLOT( emitBeginInsertItems( QgsCptCityDataItem*, int, int ) ) );
-  connect( child, SIGNAL( endInsertItems() ),
-           this, SLOT( emitEndInsertItems() ) );
-  connect( child, SIGNAL( beginRemoveItems( QgsCptCityDataItem*, int, int ) ),
-           this, SLOT( emitBeginRemoveItems( QgsCptCityDataItem*, int, int ) ) );
-  connect( child, SIGNAL( endRemoveItems() ),
-           this, SLOT( emitEndRemoveItems() ) );
+  connect( child, &QgsCptCityDataItem::beginInsertItems, this, &QgsCptCityDataItem::beginInsertItems );
+  connect( child, &QgsCptCityDataItem::endInsertItems, this, &QgsCptCityDataItem::endInsertItems );
+  connect( child, &QgsCptCityDataItem::beginRemoveItems, this, &QgsCptCityDataItem::beginRemoveItems );
+  connect( child, &QgsCptCityDataItem::endRemoveItems, this, &QgsCptCityDataItem::endRemoveItems );
 
   if ( refresh )
     emit endInsertItems();
@@ -638,14 +617,10 @@ QgsCptCityDataItem * QgsCptCityDataItem::removeChildItem( QgsCptCityDataItem * c
   emit beginRemoveItems( this, i, i );
   mChildren.remove( i );
   emit endRemoveItems();
-  disconnect( child, SIGNAL( beginInsertItems( QgsCptCityDataItem*, int, int ) ),
-              this, SLOT( emitBeginInsertItems( QgsCptCityDataItem*, int, int ) ) );
-  disconnect( child, SIGNAL( endInsertItems() ),
-              this, SLOT( emitEndInsertItems() ) );
-  disconnect( child, SIGNAL( beginRemoveItems( QgsCptCityDataItem*, int, int ) ),
-              this, SLOT( emitBeginRemoveItems( QgsCptCityDataItem*, int, int ) ) );
-  disconnect( child, SIGNAL( endRemoveItems() ),
-              this, SLOT( emitEndRemoveItems() ) );
+  disconnect( child, &QgsCptCityDataItem::beginInsertItems, this, &QgsCptCityDataItem::beginInsertItems );
+  disconnect( child, &QgsCptCityDataItem::endInsertItems, this, &QgsCptCityDataItem::endInsertItems );
+  disconnect( child, &QgsCptCityDataItem::beginRemoveItems, this, &QgsCptCityDataItem::beginRemoveItems );
+  disconnect( child, &QgsCptCityDataItem::endRemoveItems, this, &QgsCptCityDataItem::endRemoveItems );
   child->setParent( nullptr );
   return child;
 }
@@ -1668,14 +1643,10 @@ void QgsCptCityBrowserModel::endRemoveItems()
 }
 void QgsCptCityBrowserModel::connectItem( QgsCptCityDataItem* item )
 {
-  connect( item, SIGNAL( beginInsertItems( QgsCptCityDataItem*, int, int ) ),
-           this, SLOT( beginInsertItems( QgsCptCityDataItem*, int, int ) ) );
-  connect( item, SIGNAL( endInsertItems() ),
-           this, SLOT( endInsertItems() ) );
-  connect( item, SIGNAL( beginRemoveItems( QgsCptCityDataItem*, int, int ) ),
-           this, SLOT( beginRemoveItems( QgsCptCityDataItem*, int, int ) ) );
-  connect( item, SIGNAL( endRemoveItems() ),
-           this, SLOT( endRemoveItems() ) );
+  connect( item, &QgsCptCityDataItem::beginInsertItems, this, &QgsCptCityBrowserModel::beginInsertItems );
+  connect( item, &QgsCptCityDataItem::endInsertItems, this, &QgsCptCityBrowserModel::endInsertItems );
+  connect( item, &QgsCptCityDataItem::beginRemoveItems, this, &QgsCptCityBrowserModel::beginRemoveItems );
+  connect( item, &QgsCptCityDataItem::endRemoveItems, this, &QgsCptCityBrowserModel::endRemoveItems );
 }
 
 bool QgsCptCityBrowserModel::canFetchMore( const QModelIndex & parent ) const
diff --git a/src/core/symbology-ng/qgscptcityarchive.h b/src/core/symbology-ng/qgscptcityarchive.h
index 14639e4b49b..a94e61f12bc 100644
--- a/src/core/symbology-ng/qgscptcityarchive.h
+++ b/src/core/symbology-ng/qgscptcityarchive.h
@@ -188,12 +188,6 @@ class CORE_EXPORT QgsCptCityDataItem : public QObject
     QIcon mIcon;
     bool mValid;
 
-  public slots:
-    void emitBeginInsertItems( QgsCptCityDataItem* parent, int first, int last );
-    void emitEndInsertItems();
-    void emitBeginRemoveItems( QgsCptCityDataItem* parent, int first, int last );
-    void emitEndRemoveItems();
-
   signals:
     void beginInsertItems( QgsCptCityDataItem* parent, int first, int last );
     void endInsertItems();
diff --git a/src/core/symbology-ng/qgssvgcache.cpp b/src/core/symbology-ng/qgssvgcache.cpp
index ab36f84630f..bf16b9262a6 100644
--- a/src/core/symbology-ng/qgssvgcache.cpp
+++ b/src/core/symbology-ng/qgssvgcache.cpp
@@ -430,7 +430,7 @@ QByteArray QgsSvgCache::getImageData( const QString &path ) const
     request.setAttribute( QNetworkRequest::CacheSaveControlAttribute, true );
 
     reply = QgsNetworkAccessManager::instance()->get( request );
-    connect( reply, SIGNAL( downloadProgress( qint64, qint64 ) ), this, SLOT( downloadProgress( qint64, qint64 ) ) );
+    connect( reply, &QNetworkReply::downloadProgress, this, &QgsSvgCache::downloadProgress );
 
     //emit statusChanged( tr( "Downloading svg." ) );