diff --git a/.eslintrc b/.eslintrc
new file mode 100644
index 000000000..87c921c4d
--- /dev/null
+++ b/.eslintrc
@@ -0,0 +1,17 @@
+{
+  "extends": "openlayers",
+  "rules": {
+    "no-console": 0,
+    "no-extra-boolean-cast": 0,
+    "brace-style": 0,
+    "no-multiple-empty-lines": 0,
+    "valid-jsdoc": 0
+  },
+  "globals": {
+    "ol": false,
+    "goog": false,
+    "Cesium": false,
+    "olcs": false,
+    "proj4": false
+  }
+}
diff --git a/.travis.yml b/.travis.yml
index 15813002f..b559f2b9e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,3 @@
-language: python
 sudo: false
 cache:
   directories:
diff --git a/CHANGES.md b/CHANGES.md
index 5af60a928..55628d06a 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,6 +1,12 @@
 # Changelog
 
+## v 1.16 - 2016-05-30
+
 * Changes
+  * Switch to eslint.
+  * Update npm dependencies.
+  * Port to Cesium 1.21.
+  * Port to OL 3.16.0.
   * Add support for drawing rectangles according to the longitude and latitude
     curves instead of straight lines. This functionality can be activated by
     setting the olcs.polygon_kind property to 'rectangle' on the OpenLayers
diff --git a/Makefile b/Makefile
index dc56ac265..f17d40a45 100644
--- a/Makefile
+++ b/Makefile
@@ -49,7 +49,7 @@ dist-apidoc:
 	node node_modules/.bin/jsdoc -c build/jsdoc/api/conf.json -d dist/apidoc
 
 .PHONY: lint
-lint: .build/python-venv/bin/gjslint .build/gjslint.timestamp
+lint: .build/node_modules.timestamp .build/eslint.timestamp
 	@build/check-no-goog.sh
 
 .build/geojsonhint.timestamp: $(EXAMPLES_GEOJSON_FILES)
@@ -81,8 +81,8 @@ cleanall: clean
 	mkdir -p $(dir $@)
 	touch $@
 
-.build/gjslint.timestamp: $(SRC_JS_FILES)
-	.build/python-venv/bin/gjslint --jslint_error=all --strict --custom_jsdoc_tags=api $?
+.build/eslint.timestamp: $(SRC_JS_FILES)
+	./node_modules/.bin/eslint $?
 	touch $@
 
 .build/dist-examples.timestamp: cesium/Build/Cesium/Cesium.js cesium/Build/CesiumUnminified/Cesium.js dist/ol3cesium.js $(EXAMPLES_JS_FILES) $(EXAMPLES_HTML_FILES)
@@ -98,14 +98,6 @@ cleanall: clean
 	for f in dist/examples/*.html; do $(SEDI) 'sY../ol3/css/ol.cssY../ol.cssY' $$f; done
 	touch $@
 
-.build/python-venv:
-	mkdir -p $(dir $@)
-	virtualenv --no-site-packages $@
-
-.build/python-venv/bin/gjslint: .build/python-venv
-	.build/python-venv/bin/pip install "http://closure-linter.googlecode.com/files/closure_linter-latest.tar.gz"
-	touch $@
-
 dist/ol3cesium-debug.js: build/ol3cesium-debug.json $(SRC_JS_FILES) Cesium.externs.js build/build.js npm-install
 	mkdir -p $(dir $@)
 	node build/build.js $< $@
diff --git a/README.md b/README.md
index 58bc05007..16f9e2b7f 100644
--- a/README.md
+++ b/README.md
@@ -55,8 +55,6 @@ Requirements for building OL3-Cesium:
 
 * [GNU Make](http://www.gnu.org/software/make/)
 * [Node.js](http://nodejs.org/)
-* [Python](http://python.org/)
-* [Ant](http://ant.apache.org/)
 
 To get started, clone the [OL3-Cesium repository](https://github.com/openlayers/ol3-cesium) with its submodules:
 
diff --git a/build/ol3cesium.json b/build/ol3cesium.json
index 80892727c..d9e3b9db6 100644
--- a/build/ol3cesium.json
+++ b/build/ol3cesium.json
@@ -31,7 +31,6 @@
     ],
     "jscomp_off": [
       "useOfGoogBase",
-      "unnecessaryCasts",
       "lintChecks",
       "analyzerChecks"
     ],
diff --git a/cesium b/cesium
index e49fb890e..b1b249fd2 160000
--- a/cesium
+++ b/cesium
@@ -1 +1 @@
-Subproject commit e49fb890e034edc4ad519eddf1feaf1dea75566a
+Subproject commit b1b249fd2c90cbaa3f7e24a29e72bc4ab2656e21
diff --git a/ol3 b/ol3
index cd32875f3..1038b2abe 160000
--- a/ol3
+++ b/ol3
@@ -1 +1 @@
-Subproject commit cd32875f376ac85c5547f0afce1695dad4c66c8c
+Subproject commit 1038b2abea136b029c9d4c2aecaaf4028a9de606
diff --git a/package.json b/package.json
index 3617819d0..5e7262e93 100644
--- a/package.json
+++ b/package.json
@@ -16,12 +16,13 @@
     "htmlparser2": "3.9.0"
   },
   "devDependencies": {
-    "closure-util": "1.13.0",
-    "geojsonhint": "1.2.0",
-    "fs-extra": "0.26.7",
-    "graceful-fs": "4.1.3",
+    "closure-util": "1.14.0",
+    "geojsonhint": "1.2.1",
+    "fs-extra": "0.30.0",
+    "graceful-fs": "4.1.4",
     "jsdoc": "~3.4.0",
-    "jshint": "2.9.1",
+    "eslint": "2.11.0",
+    "eslint-config-openlayers": "4.1.0",
     "nomnom": "1.8.1",
     "temp": "0.8.3",
     "walk": "2.3.9"
diff --git a/src/abstractsynchronizer.js b/src/abstractsynchronizer.js
index 067c40941..5099ffd4d 100644
--- a/src/abstractsynchronizer.js
+++ b/src/abstractsynchronizer.js
@@ -138,8 +138,7 @@ olcs.AbstractSynchronizer.prototype.addLayers_ = function(root) {
  * @return {boolean} counterpart destroyed
  * @private
  */
-olcs.AbstractSynchronizer.prototype.removeAndDestroySingleLayer_ =
-    function(layer) {
+olcs.AbstractSynchronizer.prototype.removeAndDestroySingleLayer_ = function(layer) {
   var uid = goog.getUid(layer);
   var counterparts = this.layerMap[uid];
   if (!!counterparts) {
@@ -160,8 +159,7 @@ olcs.AbstractSynchronizer.prototype.removeAndDestroySingleLayer_ =
  * @param {ol.layer.Group} group
  * @private
  */
-olcs.AbstractSynchronizer.prototype.unlistenSingleGroup_ =
-    function(group) {
+olcs.AbstractSynchronizer.prototype.unlistenSingleGroup_ = function(group) {
   if (group === this.mapLayerGroup) {
     return;
   }
diff --git a/src/autorenderloop.js b/src/autorenderloop.js
index 44fb5c09c..ea55da691 100644
--- a/src/autorenderloop.js
+++ b/src/autorenderloop.js
@@ -105,8 +105,7 @@ olcs.AutoRenderLoop.prototype.enable = function() {
   };
 
   // Hacky way to force a repaint when a web worker sends something back.
-  Cesium.TaskProcessor.prototype.scheduleTask =
-      function(parameters, transferableObjects) {
+  Cesium.TaskProcessor.prototype.scheduleTask = function(parameters, transferableObjects) {
     var result = that._originalScheduleTask.call(this, parameters,
         transferableObjects);
 
diff --git a/src/featureconverter.js b/src/featureconverter.js
index 7936b6d5f..d020d50a5 100644
--- a/src/featureconverter.js
+++ b/src/featureconverter.js
@@ -73,8 +73,7 @@ olcs.FeatureConverter.prototype.onRemoveOrClearFeature_ = function(evt) {
  * @param {!Cesium.Primitive|Cesium.Label|Cesium.Billboard} primitive
  * @protected
  */
-olcs.FeatureConverter.prototype.setReferenceForPicking =
-    function(layer, feature, primitive) {
+olcs.FeatureConverter.prototype.setReferenceForPicking = function(layer, feature, primitive) {
   primitive.olLayer = layer;
   primitive.olFeature = feature;
 };
@@ -92,8 +91,7 @@ olcs.FeatureConverter.prototype.setReferenceForPicking =
  * @return {Cesium.Primitive}
  * @protected
  */
-olcs.FeatureConverter.prototype.createColoredPrimitive =
-    function(layer, feature, olGeometry, geometry, color, opt_lineWidth) {
+olcs.FeatureConverter.prototype.createColoredPrimitive = function(layer, feature, olGeometry, geometry, color, opt_lineWidth) {
   var createInstance = function(geometry, color) {
     return new Cesium.GeometryInstance({
       // always update Cesium externs before adding a property
@@ -157,8 +155,7 @@ olcs.FeatureConverter.prototype.createColoredPrimitive =
  * @return {!Cesium.Color}
  * @protected
  */
-olcs.FeatureConverter.prototype.extractColorFromOlStyle =
-    function(style, outline) {
+olcs.FeatureConverter.prototype.extractColorFromOlStyle = function(style, outline) {
   var fillColor = style.getFill() ? style.getFill().getColor() : null;
   var strokeColor = style.getStroke() ? style.getStroke().getColor() : null;
 
@@ -180,8 +177,7 @@ olcs.FeatureConverter.prototype.extractColorFromOlStyle =
  * @return {number}
  * @protected
  */
-olcs.FeatureConverter.prototype.extractLineWidthFromOlStyle =
-    function(style) {
+olcs.FeatureConverter.prototype.extractLineWidthFromOlStyle = function(style) {
   var width = style.getStroke() ? style.getStroke().getWidth() : 1;
   return Math.min(width, this.scene.maximumAliasedLineWidth);
 };
@@ -199,28 +195,26 @@ olcs.FeatureConverter.prototype.extractLineWidthFromOlStyle =
  * @return {!Cesium.PrimitiveCollection}
  * @protected
  */
-olcs.FeatureConverter.prototype.wrapFillAndOutlineGeometries =
-    function(layer, feature, olGeometry, fillGeometry, outlineGeometry,
-        olStyle) {
+olcs.FeatureConverter.prototype.wrapFillAndOutlineGeometries = function(layer, feature, olGeometry, fillGeometry, outlineGeometry, olStyle) {
   var fillColor = this.extractColorFromOlStyle(olStyle, false);
   var outlineColor = this.extractColorFromOlStyle(olStyle, true);
 
   var primitives = new Cesium.PrimitiveCollection();
   if (olStyle.getFill()) {
-    var p = this.createColoredPrimitive(layer, feature, olGeometry,
+    var p1 = this.createColoredPrimitive(layer, feature, olGeometry,
         fillGeometry, fillColor);
-    goog.asserts.assert(!!p);
-    primitives.add(p);
+    goog.asserts.assert(!!p1);
+    primitives.add(p1);
   }
 
   if (olStyle.getStroke()) {
     var width = this.extractLineWidthFromOlStyle(olStyle);
-    var p = this.createColoredPrimitive(layer, feature, olGeometry,
+    var p2 = this.createColoredPrimitive(layer, feature, olGeometry,
         outlineGeometry, outlineColor, width);
-    if (p) {
+    if (p2) {
       // Some outline geometries are not supported by Cesium in clamp to ground
       // mode. These primitives are skipped.
-      primitives.add(p);
+      primitives.add(p2);
     }
   }
 
@@ -240,8 +234,7 @@ olcs.FeatureConverter.prototype.wrapFillAndOutlineGeometries =
  * @return {!Cesium.PrimitiveCollection}
  * @protected
  */
-olcs.FeatureConverter.prototype.addTextStyle =
-    function(layer, feature, geometry, style, primitive) {
+olcs.FeatureConverter.prototype.addTextStyle = function(layer, feature, geometry, style, primitive) {
   var primitives;
   if (!(primitive instanceof Cesium.PrimitiveCollection)) {
     primitives = new Cesium.PrimitiveCollection();
@@ -276,8 +269,7 @@ olcs.FeatureConverter.prototype.addTextStyle =
  * @return {!Cesium.Billboard} newly created billboard
  * @api
  */
-olcs.FeatureConverter.prototype.csAddBillboard =
-    function(billboards, bbOptions, layer, feature, geometry, style) {
+olcs.FeatureConverter.prototype.csAddBillboard = function(billboards, bbOptions, layer, feature, geometry, style) {
   var bb = billboards.add(bbOptions);
   this.setReferenceForPicking(layer, feature, bb);
   return bb;
@@ -294,8 +286,7 @@ olcs.FeatureConverter.prototype.csAddBillboard =
  * @return {!Cesium.PrimitiveCollection} primitives
  * @api
  */
-olcs.FeatureConverter.prototype.olCircleGeometryToCesium =
-    function(layer, feature, olGeometry, projection, olStyle) {
+olcs.FeatureConverter.prototype.olCircleGeometryToCesium = function(layer, feature, olGeometry, projection, olStyle) {
 
   olGeometry = olcs.core.olGeometryCloneTo4326(olGeometry, projection);
   goog.asserts.assert(olGeometry.getType() == 'Circle');
@@ -345,8 +336,7 @@ olcs.FeatureConverter.prototype.olCircleGeometryToCesium =
  * @return {!Cesium.PrimitiveCollection} primitives
  * @api
  */
-olcs.FeatureConverter.prototype.olLineStringGeometryToCesium =
-    function(layer, feature, olGeometry, projection, olStyle) {
+olcs.FeatureConverter.prototype.olLineStringGeometryToCesium = function(layer, feature, olGeometry, projection, olStyle) {
 
   olGeometry = olcs.core.olGeometryCloneTo4326(olGeometry, projection);
   goog.asserts.assert(olGeometry.getType() == 'LineString');
@@ -391,8 +381,7 @@ olcs.FeatureConverter.prototype.olLineStringGeometryToCesium =
  * @return {!Cesium.PrimitiveCollection} primitives
  * @api
  */
-olcs.FeatureConverter.prototype.olPolygonGeometryToCesium =
-    function(layer, feature, olGeometry, projection, olStyle) {
+olcs.FeatureConverter.prototype.olPolygonGeometryToCesium = function(layer, feature, olGeometry, projection, olStyle) {
 
   olGeometry = olcs.core.olGeometryCloneTo4326(olGeometry, projection);
   goog.asserts.assert(olGeometry.getType() == 'Polygon');
@@ -476,8 +465,7 @@ olcs.FeatureConverter.prototype.olPolygonGeometryToCesium =
  * @return {!Cesium.HeightReference}
  * @api
  */
-olcs.FeatureConverter.prototype.getHeightReference =
-    function(layer, feature, geometry) {
+olcs.FeatureConverter.prototype.getHeightReference = function(layer, feature, geometry) {
 
   // Read from the geometry
   var altitudeMode = geometry.get('altitudeMode');
@@ -516,8 +504,7 @@ olcs.FeatureConverter.prototype.getHeightReference =
  * @return {Cesium.Primitive} primitives
  * @api
  */
-olcs.FeatureConverter.prototype.olPointGeometryToCesium =
-    function(layer, feature, olGeometry, projection, style, billboards,
+olcs.FeatureConverter.prototype.olPointGeometryToCesium = function(layer, feature, olGeometry, projection, style, billboards,
     opt_newBillboardCallback) {
   goog.asserts.assert(olGeometry.getType() == 'Point');
   olGeometry = olcs.core.olGeometryCloneTo4326(olGeometry, projection);
@@ -631,8 +618,7 @@ olcs.FeatureConverter.prototype.olPointGeometryToCesium =
  * @return {Cesium.Primitive} primitives
  * @api
  */
-olcs.FeatureConverter.prototype.olMultiGeometryToCesium =
-    function(layer, feature, geometry, projection, olStyle, billboards,
+olcs.FeatureConverter.prototype.olMultiGeometryToCesium = function(layer, feature, geometry, projection, olStyle, billboards,
     opt_newBillboardCallback) {
   // Do not reproject to 4326 now because it will be done later.
 
@@ -693,8 +679,7 @@ olcs.FeatureConverter.prototype.olMultiGeometryToCesium =
  * @return {Cesium.LabelCollection} Cesium primitive
  * @api
  */
-olcs.FeatureConverter.prototype.olGeometry4326TextPartToCesium =
-    function(layer, feature, geometry, style) {
+olcs.FeatureConverter.prototype.olGeometry4326TextPartToCesium = function(layer, feature, geometry, style) {
   var text = style.getText();
   goog.asserts.assert(goog.isDef(text));
 
@@ -795,8 +780,7 @@ olcs.FeatureConverter.prototype.olGeometry4326TextPartToCesium =
  * @return {Cesium.Material}
  * @api
  */
-olcs.FeatureConverter.prototype.olStyleToCesium =
-    function(feature, style, outline) {
+olcs.FeatureConverter.prototype.olStyleToCesium = function(feature, style, outline) {
   var fill = style.getFill();
   var stroke = style.getStroke();
   if ((outline && !stroke) || (!outline && !fill)) {
@@ -834,8 +818,7 @@ olcs.FeatureConverter.prototype.olStyleToCesium =
  * @return {ol.style.Style} null if no style is available
  * @api
  */
-olcs.FeatureConverter.prototype.computePlainStyle =
-    function(layer, feature, fallbackStyleFunction, resolution) {
+olcs.FeatureConverter.prototype.computePlainStyle = function(layer, feature, fallbackStyleFunction, resolution) {
   /**
    * @type {ol.FeatureStyleFunction|undefined}
    */
@@ -877,8 +860,7 @@ olcs.FeatureConverter.prototype.computePlainStyle =
  * @return {Cesium.Primitive} primitives
  * @api
  */
-olcs.FeatureConverter.prototype.olFeatureToCesium =
-    function(layer, feature, style, context, opt_geom) {
+olcs.FeatureConverter.prototype.olFeatureToCesium = function(layer, feature, style, context, opt_geom) {
   var geom = opt_geom || feature.getGeometry();
   var proj = context.projection;
   if (!geom) {
@@ -932,13 +914,13 @@ olcs.FeatureConverter.prototype.olFeatureToCesium =
     case 'MultiPoint':
     case 'MultiLineString':
     case 'MultiPolygon':
-      var result = this.olMultiGeometryToCesium(layer, feature, geom, proj,
+      var result2 = this.olMultiGeometryToCesium(layer, feature, geom, proj,
           style, context.billboards, newBillboardAddedCallback);
-      if (!result) {
+      if (!result2) {
         // no wrapping primitive
         return null;
       } else {
-        return result;
+        return result2;
       }
     case 'LinearRing':
       throw new Error('LinearRing should only be part of polygon.');
@@ -958,8 +940,7 @@ olcs.FeatureConverter.prototype.olFeatureToCesium =
  * @return {!olcs.core.VectorLayerCounterpart}
  * @api
  */
-olcs.FeatureConverter.prototype.olVectorLayerToCesium =
-    function(olLayer, olView, featurePrimitiveMap) {
+olcs.FeatureConverter.prototype.olVectorLayerToCesium = function(olLayer, olView, featurePrimitiveMap) {
   var proj = olView.getProjection();
   var resolution = olView.getResolution();
 
@@ -1025,8 +1006,7 @@ olcs.FeatureConverter.prototype.olVectorLayerToCesium =
  * @return {Cesium.Primitive}
  * @api
  */
-olcs.FeatureConverter.prototype.convert =
-    function(layer, view, feature, context) {
+olcs.FeatureConverter.prototype.convert = function(layer, view, feature, context) {
   var proj = view.getProjection();
   var resolution = view.getResolution();
 
diff --git a/src/ol3cesium.js b/src/ol3cesium.js
index 3adfc3763..525eaed34 100644
--- a/src/ol3cesium.js
+++ b/src/ol3cesium.js
@@ -174,8 +174,7 @@ olcs.OLCesium = function(options) {
   });
 
   var synchronizers = goog.isDef(options.createSynchronizers) ?
-      options.createSynchronizers(this.map_, this.scene_) :
-      [
+      options.createSynchronizers(this.map_, this.scene_) : [
         new olcs.RasterSynchronizer(this.map_, this.scene_),
         new olcs.VectorSynchronizer(this.map_, this.scene_)
       ];
@@ -319,10 +318,11 @@ olcs.OLCesium.prototype.setEnabled = function(enable) {
   // some Cesium operations are operating with canvas.clientWidth,
   // so we can't remove it from DOM or even make display:none;
   this.container_.style.visibility = this.enabled_ ? 'visible' : 'hidden';
+  var interactions;
   if (this.enabled_) {
     this.throwOnUnitializedMap_();
     if (this.isOverMap_) {
-      var interactions = this.map_.getInteractions();
+      interactions = this.map_.getInteractions();
       interactions.forEach(function(el, i, arr) {
         this.pausedInteractions_.push(el);
       }, this);
@@ -338,7 +338,7 @@ olcs.OLCesium.prototype.setEnabled = function(enable) {
     this.cesiumRenderingDelay_.start();
   } else {
     if (this.isOverMap_) {
-      var interactions = this.map_.getInteractions();
+      interactions = this.map_.getInteractions();
       this.pausedInteractions_.forEach(function(interaction) {
         interactions.push(interaction);
       });
diff --git a/src/rastersynchronizer.js b/src/rastersynchronizer.js
index e27fbbf37..1b93b31bd 100644
--- a/src/rastersynchronizer.js
+++ b/src/rastersynchronizer.js
@@ -53,8 +53,7 @@ olcs.RasterSynchronizer.prototype.destroyCesiumObject = function(object) {
 /**
  * @inheritDoc
  */
-olcs.RasterSynchronizer.prototype.removeSingleCesiumObject =
-    function(object, destroy) {
+olcs.RasterSynchronizer.prototype.removeSingleCesiumObject = function(object, destroy) {
   this.cesiumLayers_.remove(object, destroy);
   this.ourLayers_.remove(object, false);
 };
@@ -82,8 +81,7 @@ olcs.RasterSynchronizer.prototype.removeAllCesiumObjects = function(destroy) {
  * (or supported)
  * @protected
  */
-olcs.RasterSynchronizer.prototype.convertLayerToCesiumImageries =
-    function(olLayer, viewProj) {
+olcs.RasterSynchronizer.prototype.convertLayerToCesiumImageries = function(olLayer, viewProj) {
   var result = olcs.core.tileLayerToImageryLayer(olLayer, viewProj);
   return result ? [result] : null;
 };
@@ -92,8 +90,7 @@ olcs.RasterSynchronizer.prototype.convertLayerToCesiumImageries =
 /**
  * @inheritDoc
  */
-olcs.RasterSynchronizer.prototype.createSingleLayerCounterparts =
-    function(olLayer) {
+olcs.RasterSynchronizer.prototype.createSingleLayerCounterparts = function(olLayer) {
   var viewProj = this.view.getProjection();
   var cesiumObjects = this.convertLayerToCesiumImageries(olLayer, viewProj);
   if (!goog.isNull(cesiumObjects)) {
diff --git a/src/vectorsynchronizer.js b/src/vectorsynchronizer.js
index 3aad33e8f..8a31f791b 100644
--- a/src/vectorsynchronizer.js
+++ b/src/vectorsynchronizer.js
@@ -58,8 +58,7 @@ olcs.VectorSynchronizer.prototype.destroyCesiumObject = function(object) {
 /**
  * @inheritDoc
  */
-olcs.VectorSynchronizer.prototype.removeSingleCesiumObject =
-    function(object, destroy) {
+olcs.VectorSynchronizer.prototype.removeSingleCesiumObject = function(object, destroy) {
   object.destroy();
   this.csAllPrimitives_.destroyPrimitives = destroy;
   this.csAllPrimitives_.remove(object.getRootPrimitive());
@@ -85,8 +84,7 @@ olcs.VectorSynchronizer.prototype.removeAllCesiumObjects = function(destroy) {
 /**
  * @inheritDoc
  */
-olcs.VectorSynchronizer.prototype.createSingleLayerCounterparts =
-    function(olLayer) {
+olcs.VectorSynchronizer.prototype.createSingleLayerCounterparts = function(olLayer) {
   if (!(olLayer instanceof ol.layer.Vector) &&
       !(olLayer instanceof ol.layer.Image &&
       olLayer.getSource() instanceof ol.source.ImageVector)) {