diff --git a/jest.config.js b/jest.config.js
index 38623dcd40..f167aac791 100644
--- a/jest.config.js
+++ b/jest.config.js
@@ -20,7 +20,7 @@ module.exports = {
     '<rootDir>/dist/'
   ],
   transformIgnorePatterns: [
-    'node_modules/(?!(ol|@camptocamp/inkmap|@terrestris/react-util|d3-selection)/)'
+    'node_modules/(?!(ol|@camptocamp/inkmap|@terrestris/react-util|d3-selection|color-space|color-*[a-z]*)|(rc-*[a-z]*)/)'
   ],
   setupFiles: [
     '<rootDir>/jest/__mocks__/matchMediaMock.js'
diff --git a/jest/setup.js b/jest/setup.js
index b00302254a..57ba4306ad 100644
--- a/jest/setup.js
+++ b/jest/setup.js
@@ -1,12 +1,13 @@
-import Enzyme from 'enzyme';
-import Adapter from '@cfaester/enzyme-adapter-react-18';
 import 'whatwg-fetch';
 import 'jest-canvas-mock';
 import '@testing-library/jest-dom';
 import 'regenerator-runtime/runtime';
+
+import Adapter from '@cfaester/enzyme-adapter-react-18';
+import Enzyme from 'enzyme';
 import {
-  TextEncoder,
-  TextDecoder
+  TextDecoder,
+  TextEncoder
 } from 'util';
 
 Object.assign(global, {
diff --git a/package-lock.json b/package-lock.json
index 340d3f58bc..8e14c0344e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -45,7 +45,7 @@
         "@terrestris/eslint-config-typescript": "^5.0.0",
         "@terrestris/ol-util": "^14.0.0",
         "@testing-library/dom": "^9.3.3",
-        "@testing-library/jest-dom": "^6.1.4",
+        "@testing-library/jest-dom": "^6.4.2",
         "@testing-library/react": "^14.0.0",
         "@testing-library/user-event": "^14.5.1",
         "@types/enzyme": "^3.10.15",
diff --git a/package.json b/package.json
index 7d4da6fdd1..4172aa52b3 100644
--- a/package.json
+++ b/package.json
@@ -104,7 +104,7 @@
     "@terrestris/eslint-config-typescript": "^5.0.0",
     "@terrestris/ol-util": "^14.0.0",
     "@testing-library/dom": "^9.3.3",
-    "@testing-library/jest-dom": "^6.1.4",
+    "@testing-library/jest-dom": "^6.4.2",
     "@testing-library/react": "^14.0.0",
     "@testing-library/user-event": "^14.5.1",
     "@types/enzyme": "^3.10.15",
diff --git a/src/Button/CopyButton/CopyButton.tsx b/src/Button/CopyButton/CopyButton.tsx
index 1257068ee9..24111f30c1 100644
--- a/src/Button/CopyButton/CopyButton.tsx
+++ b/src/Button/CopyButton/CopyButton.tsx
@@ -1,7 +1,6 @@
 import AnimateUtil from '@terrestris/ol-util/dist/AnimateUtil/AnimateUtil';
 import useMap from '@terrestris/react-util/dist/Hooks/useMap/useMap';
 import { DigitizeUtil } from '@terrestris/react-util/dist/Util/DigitizeUtil';
-import OlGeometry from 'ol/geom/Geometry';
 import { SelectEvent as OlSelectEvent } from 'ol/interaction/Select';
 import OlVectorLayer from 'ol/layer/Vector';
 import OlVectorSource from 'ol/source/Vector';
@@ -19,7 +18,7 @@ interface OwnProps {
    * The vector layer which will be used for digitize features.
    * The standard digitizeLayer can be retrieved via `DigitizeUtil.getDigitizeLayer(map)`.
    */
-  digitizeLayer?: OlVectorLayer<OlVectorSource<OlGeometry>>;
+  digitizeLayer?: OlVectorLayer<OlVectorSource>;
   /**
    * Listener function for the 'select' event of the ol.interaction.Select
    * if in `Copy` mode.
@@ -42,7 +41,7 @@ const CopyButton: React.FC<CopyButtonProps> = ({
   ...passThroughProps
 }) => {
 
-  const [layers, setLayers] = useState<[OlVectorLayer<OlVectorSource<OlGeometry>>]|null>(null);
+  const [layers, setLayers] = useState<[OlVectorLayer<OlVectorSource>]|null>(null);
 
   const map = useMap();
 
diff --git a/src/Button/DeleteButton/DeleteButton.tsx b/src/Button/DeleteButton/DeleteButton.tsx
index 605d83ac02..712b1ed396 100644
--- a/src/Button/DeleteButton/DeleteButton.tsx
+++ b/src/Button/DeleteButton/DeleteButton.tsx
@@ -1,6 +1,5 @@
 import useMap from '@terrestris/react-util/dist/Hooks/useMap/useMap';
 import { DigitizeUtil } from '@terrestris/react-util/dist/Util/DigitizeUtil';
-import OlGeometry from 'ol/geom/Geometry';
 import { SelectEvent as OlSelectEvent } from 'ol/interaction/Select';
 import OlVectorLayer from 'ol/layer/Vector';
 import OlVectorSource from 'ol/source/Vector';
@@ -15,7 +14,7 @@ interface OwnProps {
    * The vector layer which will be used for digitize features.
    * The standard digitizeLayer can be retrieved via `DigitizeUtil.getDigitizeLayer(map)`.
    */
-  digitizeLayer?: OlVectorLayer<OlVectorSource<OlGeometry>>;
+  digitizeLayer?: OlVectorLayer<OlVectorSource>;
   /**
    * Listener function for the 'select' event of the ol.interaction.Select
    * if in `Delete` mode.
@@ -39,7 +38,7 @@ export const DeleteButton: React.FC<DeleteButtonProps> = ({
   onFeatureRemove,
   ...passThroughProps
 }) => {
-  const [layers, setLayers] = useState<[OlVectorLayer<OlVectorSource<OlGeometry>>]|null>(null);
+  const [layers, setLayers] = useState<[OlVectorLayer<OlVectorSource>]|null>(null);
 
   const map = useMap();
 
diff --git a/src/Button/DrawButton/DrawButton.spec.tsx b/src/Button/DrawButton/DrawButton.spec.tsx
index 7f2c544f01..9387db3651 100644
--- a/src/Button/DrawButton/DrawButton.spec.tsx
+++ b/src/Button/DrawButton/DrawButton.spec.tsx
@@ -14,7 +14,7 @@ import DrawButton from './DrawButton';
 
 describe('<DrawButton />', () => {
 
-  let map;
+  let map: OlMap;
 
   beforeEach(() => {
     map = new OlMap({
diff --git a/src/Button/DrawButton/DrawButton.tsx b/src/Button/DrawButton/DrawButton.tsx
index 7b352f6cd9..4d4b32a33e 100644
--- a/src/Button/DrawButton/DrawButton.tsx
+++ b/src/Button/DrawButton/DrawButton.tsx
@@ -58,7 +58,7 @@ interface OwnProps {
    * The vector layer which will be used for digitize features.
    * The standard digitizeLayer can be retrieved via `DigitizeUtil.getDigitizeLayer(map)`.
    */
-  digitizeLayer?: OlVectorLayer<OlVectorSource<OlGeometry>>;
+  digitizeLayer?: OlVectorLayer<OlVectorSource>;
   /**
    * Title for modal used for input of labels for digitize features.
    */
@@ -112,10 +112,10 @@ const DrawButton: React.FC<DrawButtonProps> = ({
 }) => {
 
   const [drawInteraction, setDrawInteraction] = useState<OlInteractionDraw>();
-  const [layer, setLayer] = useState<OlVectorLayer<OlVectorSource<OlGeometry>> | null>(null);
+  const [layer, setLayer] = useState<OlVectorLayer<OlVectorSource> | null>(null);
 
   /**
-   * Currently drawn feature which should be represent as label or postit.
+   * Currently drawn feature which should be represented as label or post-it.
    */
   const [digitizeTextFeature, setDigitizeTextFeature] = useState<OlFeature<OlGeometry> | null>(null);
 
diff --git a/src/Button/GeoLocationButton/GeoLocationButton.spec.tsx b/src/Button/GeoLocationButton/GeoLocationButton.spec.tsx
index 222da947a7..04e741ce4d 100644
--- a/src/Button/GeoLocationButton/GeoLocationButton.spec.tsx
+++ b/src/Button/GeoLocationButton/GeoLocationButton.spec.tsx
@@ -7,13 +7,10 @@ import { render, within } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 import * as React from 'react';
 
-import TestUtil from '../../Util/TestUtil';
 import GeoLocationButton from './GeoLocationButton';
 
 describe('<GeoLocationButton />', () => {
 
-  let map;
-
   beforeAll(() => {
     enableGeolocationMock();
   });
@@ -22,10 +19,6 @@ describe('<GeoLocationButton />', () => {
     disableGeolocationMock();
   });
 
-  beforeEach(() => {
-    map = TestUtil.createMap();
-  });
-
   describe('#Basics', () => {
 
     it('is defined', () => {
diff --git a/src/Button/MeasureButton/MeasureButton.spec.tsx b/src/Button/MeasureButton/MeasureButton.spec.tsx
index 573682a135..ce8f8689bb 100644
--- a/src/Button/MeasureButton/MeasureButton.spec.tsx
+++ b/src/Button/MeasureButton/MeasureButton.spec.tsx
@@ -1,19 +1,21 @@
 import MeasureUtil from '@terrestris/ol-util/dist/MeasureUtil/MeasureUtil';
+import {EventTargetLike} from 'ol/events/Target';
 import OlFeature from 'ol/Feature';
 import OlGeomLineString from 'ol/geom/LineString';
 import OlGeomPoint from 'ol/geom/Point';
 import OlGeomPolygon from 'ol/geom/Polygon';
-import OlInteractionDraw from 'ol/interaction/Draw';
+import OlInteractionDraw, {DrawEvent} from 'ol/interaction/Draw';
 import OlLayerVector from 'ol/layer/Vector';
+import OlMap from 'ol/Map';
 import * as OlObservable from 'ol/Observable';
 import OlOverlay from 'ol/Overlay';
 
-import TestUtil from '../../Util/TestUtil';
-import MeasureButton from './MeasureButton';
+import TestUtil, {Wrapper} from '../../Util/TestUtil';
+import MeasureButton, {MeasureButtonProps} from './MeasureButton';
 
 describe('<MeasureButton />', () => {
 
-  let map;
+  let map: OlMap;
 
   beforeEach(() => {
     map = TestUtil.createMap();
@@ -57,24 +59,25 @@ describe('<MeasureButton />', () => {
         pressed: true
       });
 
-      expect(wrapper.props().measureLayerName).toBe('measureLayerName');
-      expect(wrapper.props().fillColor).toBe('#ff0000');
-      expect(wrapper.props().strokeColor).toBe('#0000ff');
-      expect(wrapper.props().showMeasureInfoOnClickedPoints).toBe(true);
-      expect(wrapper.props().clickToDrawText).toBe('Click to draw');
-      expect(wrapper.props().continuePolygonMsg).toBe('Continue draw polygon');
-      expect(wrapper.props().continueLineMsg).toBe('Continue draw line');
-      expect(wrapper.props().continueAngleMsg).toBe('Continue draw angle');
-      expect(wrapper.props().decimalPlacesInTooltips).toBe(5);
-      expect(wrapper.props().measureTooltipCssClasses).toEqual({
+      const props: MeasureButtonProps = wrapper.props() as MeasureButtonProps;
+      expect(props.measureLayerName).toBe('measureLayerName');
+      expect(props.fillColor).toBe('#ff0000');
+      expect(props.strokeColor).toBe('#0000ff');
+      expect(props.showMeasureInfoOnClickedPoints).toBe(true);
+      expect(props.clickToDrawText).toBe('Click to draw');
+      expect(props.continuePolygonMsg).toBe('Continue draw polygon');
+      expect(props.continueLineMsg).toBe('Continue draw line');
+      expect(props.continueAngleMsg).toBe('Continue draw angle');
+      expect(props.decimalPlacesInTooltips).toBe(5);
+      expect(props.measureTooltipCssClasses).toEqual({
         tooltip: 'tooltip-cls',
         tooltipDynamic: 'dynamic-tooltip-cls',
         tooltipStatic: 'static-tooltip-cls'
       });
-      expect(wrapper.props().pressed).toBe(true);
+      expect(props.pressed).toBe(true);
 
-      expect(wrapper.props().measureTooltipCssClasses).toBeInstanceOf(Object);
-      expect(wrapper.find('button', {pressed: true}).length).toBe(1);
+      expect(props.measureTooltipCssClasses).toBeInstanceOf(Object);
+      expect(wrapper.find('button').length).toBe(1);
     });
 
   });
@@ -111,12 +114,12 @@ describe('<MeasureButton />', () => {
           pressed: true
         });
 
-        const instance = wrapper.instance();
+        const instance: MeasureButton = wrapper.instance() as MeasureButton;
 
-        expect(instance._drawInteraction.getActive()).toBe(true);
-        expect(instance._eventKeys.drawstart).toBeDefined();
-        expect(instance._eventKeys.drawend).toBeDefined();
-        expect(instance._eventKeys.pointermove).toBeDefined();
+        expect(instance._drawInteraction?.getActive()).toBe(true);
+        expect(instance._eventKeys?.drawstart).toBeDefined();
+        expect(instance._eventKeys?.drawend).toBeDefined();
+        expect(instance._eventKeys?.pointermove).toBeDefined();
 
       });
     });
@@ -129,7 +132,7 @@ describe('<MeasureButton />', () => {
           measureType: 'line'
         });
 
-        const instance = wrapper.instance();
+        const instance: MeasureButton = wrapper.instance() as MeasureButton;
 
         expect(instance._measureLayer).toBeDefined();
         expect(instance._measureLayer).toBeInstanceOf(OlLayerVector);
@@ -145,11 +148,11 @@ describe('<MeasureButton />', () => {
           pressed: true
         });
 
-        const instance = wrapper.instance();
+        const instance: MeasureButton = wrapper.instance() as MeasureButton;
 
         expect(instance._drawInteraction).toBeDefined();
         expect(instance._drawInteraction).toBeInstanceOf(OlInteractionDraw);
-        expect(instance._drawInteraction.getActive()).toBeTruthy();
+        expect(instance._drawInteraction?.getActive()).toBeTruthy();
       });
     });
 
@@ -162,19 +165,19 @@ describe('<MeasureButton />', () => {
           pressed: true
         });
 
-        const instance = wrapper.instance();
+        const instance: MeasureButton = wrapper.instance() as MeasureButton;
 
         const removeHelpTooltipSpy = jest.spyOn(instance, 'removeHelpTooltip');
         const removeMeasureTooltipSpy = jest.spyOn(instance, 'removeMeasureTooltip');
         const createHelpTooltipSpy = jest.spyOn(instance, 'createHelpTooltip');
         const createMeasureTooltipSpy = jest.spyOn(instance, 'createMeasureTooltip');
 
-        instance._drawInteraction.setActive(false);
+        instance._drawInteraction?.setActive(false);
 
         expect(removeHelpTooltipSpy).toHaveBeenCalledTimes(1);
         expect(removeMeasureTooltipSpy).toHaveBeenCalledTimes(1);
 
-        instance._drawInteraction.setActive(true);
+        instance._drawInteraction?.setActive(true);
 
         expect(createHelpTooltipSpy).toHaveBeenCalledTimes(1);
         expect(createMeasureTooltipSpy).toHaveBeenCalledTimes(1);
@@ -188,9 +191,9 @@ describe('<MeasureButton />', () => {
 
     describe('#drawStart', () => {
 
-      let mockEvt;
-      let wrapper;
-      let instance;
+      let mockEvt: Partial<DrawEvent>;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
 
       beforeEach(() => {
         mockEvt = {
@@ -203,17 +206,17 @@ describe('<MeasureButton />', () => {
           measureType: 'line',
           showMeasureInfoOnClickedPoints: true
         });
-        wrapper.instance()._measureLayer.getSource().addFeature(mockEvt.feature);
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
+        instance._measureLayer?.getSource()?.addFeature(mockEvt.feature!);
       });
 
       it('sets the feature', () => {
-        instance.onDrawStart(mockEvt);
+        instance.onDrawStart(mockEvt as DrawEvent);
         expect(instance._feature).toBe(mockEvt.feature);
       });
 
       it('sets event key for click', () => {
-        instance.onDrawStart(mockEvt);
+        instance.onDrawStart(mockEvt as DrawEvent);
         expect(instance._eventKeys.click).toBeDefined();
       });
 
@@ -221,9 +224,9 @@ describe('<MeasureButton />', () => {
         const cleanupTooltipsSpy = jest.spyOn(instance, 'cleanupTooltips');
         const createMeasureTooltipSpy = jest.spyOn(instance, 'createMeasureTooltip');
         const createHelpTooltipSpy = jest.spyOn(instance, 'createHelpTooltip');
-        const clearSpy = jest.spyOn(wrapper.instance()._measureLayer.getSource(), 'clear');
+        const clearSpy = jest.spyOn(instance._measureLayer?.getSource()!, 'clear');
 
-        instance.onDrawStart(mockEvt);
+        instance.onDrawStart(mockEvt as DrawEvent);
 
         expect(cleanupTooltipsSpy).toHaveBeenCalledTimes(1);
         expect(createMeasureTooltipSpy).toHaveBeenCalledTimes(1);
@@ -239,9 +242,9 @@ describe('<MeasureButton />', () => {
 
     describe('#drawEnd', () => {
 
-      let wrapper;
-      let instance;
-      let mockEvt;
+      let mockEvt: Partial<DrawEvent>;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
@@ -249,7 +252,7 @@ describe('<MeasureButton />', () => {
           measureType: 'line',
           showMeasureInfoOnClickedPoints: true
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
         mockEvt = {
           feature: new OlFeature({
             geometry: new OlGeomPoint([0, 0])
@@ -259,11 +262,17 @@ describe('<MeasureButton />', () => {
 
       it ('unsets click event key', () => {
 
-        instance._eventKeys.click = jest.fn();
+        instance._eventKeys.click = {
+          target: {
+            removeEventListener: jest.fn()
+          } as unknown as EventTargetLike,
+          listener: jest.fn(),
+          type: 'click'
+        };
 
         const unByKeySpy = jest.spyOn(OlObservable, 'unByKey');
 
-        instance.onDrawEnd(mockEvt);
+        instance.onDrawEnd(mockEvt as DrawEvent);
 
         expect(unByKeySpy).toHaveBeenCalledTimes(1);
 
@@ -275,7 +284,7 @@ describe('<MeasureButton />', () => {
           showMeasureInfoOnClickedPoints: true
         });
         const removeMeasureTooltipSpy = jest.spyOn(instance, 'removeMeasureTooltip');
-        instance.onDrawEnd(mockEvt);
+        instance.onDrawEnd(mockEvt as DrawEvent);
         expect(removeMeasureTooltipSpy).toHaveBeenCalledTimes(1);
         removeMeasureTooltipSpy.mockRestore();
       });
@@ -286,16 +295,16 @@ describe('<MeasureButton />', () => {
         });
 
         instance.createMeasureTooltip();
-        instance.onDrawEnd(mockEvt);
+        instance.onDrawEnd(mockEvt as DrawEvent);
 
         const expectedClassName = 'react-geo-measure-tooltip react-geo-measure-tooltip-static';
         const expectedOffset = [0, -7];
-        expect(instance._measureTooltipElement.className).toContain(expectedClassName);
-        expect(instance._measureTooltip.getOffset()).toEqual(expectedOffset);
+        expect(instance._measureTooltipElement?.className).toContain(expectedClassName);
+        expect(instance._measureTooltip?.getOffset()).toEqual(expectedOffset);
       });
 
       it ('unsets the feature', () => {
-        instance.onDrawEnd(mockEvt);
+        instance.onDrawEnd(mockEvt as DrawEvent);
         expect(instance._feature).toBeNull();
       });
 
@@ -304,7 +313,7 @@ describe('<MeasureButton />', () => {
           showMeasureInfoOnClickedPoints: true
         });
         const createMeasureTooltipSpy = jest.spyOn(instance, 'createMeasureTooltip');
-        instance.onDrawEnd(mockEvt);
+        instance.onDrawEnd(mockEvt as DrawEvent);
         expect(createMeasureTooltipSpy).toHaveBeenCalledTimes(1);
         createMeasureTooltipSpy.mockRestore();
       });
@@ -312,17 +321,17 @@ describe('<MeasureButton />', () => {
 
     describe('#addMeasureStopTooltip', () => {
 
-      let wrapper;
-      let instance;
-      let coordinate;
-      let mockLineFeat;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
+      let coordinate: number[];
+      let mockLineFeat: OlFeature<OlGeomLineString>;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
         coordinate = [100, 100];
         mockLineFeat = new OlFeature({
           geometry: new OlGeomLineString([[0, 0], [0, 100]])
@@ -337,7 +346,8 @@ describe('<MeasureButton />', () => {
         expect(instance._feature).toBeDefined();
         expect(instance._feature.getGeometry()).toBeDefined();
 
-        const value = MeasureUtil.formatLength(instance._feature.getGeometry(), map, 2);
+        const geometry = instance._feature?.getGeometry() as OlGeomLineString;
+        const value = MeasureUtil.formatLength(geometry, map, 2);
         expect(value).toBe('99.89 m');
       });
 
@@ -364,7 +374,8 @@ describe('<MeasureButton />', () => {
         expect(instance._feature).toBeDefined();
         expect(instance._feature.getGeometry()).toBeDefined();
 
-        const value = MeasureUtil.formatArea(instance._feature.getGeometry(), map, 2);
+        const geometry = instance._feature?.getGeometry() as OlGeomPolygon;
+        const value = MeasureUtil.formatArea(geometry, map, 2);
         expect(value).toBe('99.78 m<sup>2</sup>');
       });
 
@@ -377,7 +388,8 @@ describe('<MeasureButton />', () => {
         instance._feature = mockLineFeat;
         instance.addMeasureStopTooltip(coordinate);
 
-        const value = MeasureUtil.formatLength(instance._feature.getGeometry(), map, 2);
+        const geometry = instance._feature?.getGeometry() as OlGeomLineString;
+        const value = MeasureUtil.formatLength(geometry, map, 2);
         expect(parseInt(value, 10)).toBeGreaterThan(10);
 
         const overlays = map.getOverlays();
@@ -386,7 +398,7 @@ describe('<MeasureButton />', () => {
         const overlay = overlays.getArray()[0];
         const offset = overlay.getOffset();
         const positioning = overlay.getPositioning();
-        const className = overlay.getElement().className;
+        const className = overlay.getElement()?.className;
 
         expect(offset).toEqual([0, -15]);
         expect(positioning).toBe('bottom-center');
@@ -400,19 +412,21 @@ describe('<MeasureButton />', () => {
 
     describe('#createMeasureTooltip', () => {
 
-      let wrapper;
-      let instance;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
       });
 
       it('returns undefined if measureTooltipElement already set', () => {
-        instance._measureTooltipElement = 'some value';
+        const div = document.createElement('div');
+        div.innerHTML = 'some value';
+        instance._measureTooltipElement = div;
         const expectedOutput = instance.createMeasureTooltip();
         expect(expectedOutput).toBeUndefined();
       });
@@ -427,7 +441,7 @@ describe('<MeasureButton />', () => {
         const overlay = overlays.getArray()[0];
         const offset = overlay.getOffset();
         const positioning = overlay.getPositioning();
-        const className = overlay.getElement().className;
+        const className = overlay.getElement()?.className;
 
         expect(offset).toEqual([0, -15]);
         expect(positioning).toBe('bottom-center');
@@ -437,19 +451,21 @@ describe('<MeasureButton />', () => {
 
     describe('#createHelpTooltip', () => {
 
-      let wrapper;
-      let instance;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
       });
 
       it('returns undefined if _helpTooltipElement already set', () => {
-        instance._helpTooltipElement = 'some value';
+        const div = document.createElement('div');
+        div.innerHTML = 'some value';
+        instance._helpTooltipElement = div;
         const expectedOutput = instance.createHelpTooltip();
         expect(expectedOutput).toBeUndefined();
       });
@@ -464,7 +480,7 @@ describe('<MeasureButton />', () => {
         const overlay = overlays.getArray()[0];
         const offset = overlay.getOffset();
         const positioning = overlay.getPositioning();
-        const className = overlay.getElement().className;
+        const className = overlay.getElement()?.className;
 
         expect(offset).toEqual([15, 0]);
         expect(positioning).toBe('center-left');
@@ -474,15 +490,15 @@ describe('<MeasureButton />', () => {
 
     describe('#removeHelpTooltip', () => {
 
-      let wrapper;
-      let instance;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
       });
 
       it ('removes help tooltip overlay from the map', () => {
@@ -511,15 +527,15 @@ describe('<MeasureButton />', () => {
 
     describe('#removeMeasureTooltip', () => {
 
-      let wrapper;
-      let instance;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
       });
 
       it ('removes measure tooltip overlay from the map', () => {
@@ -548,19 +564,19 @@ describe('<MeasureButton />', () => {
 
     describe('#cleanupTooltips', () => {
 
-      let wrapper;
-      let instance;
-      let tooltipDiv1;
-      let tooltipDiv2;
-      let tooltip1;
-      let tooltip2;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
+      let tooltipDiv1: HTMLDivElement;
+      let tooltipDiv2: HTMLDivElement;
+      let tooltip1: OlOverlay;
+      let tooltip2: OlOverlay;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
 
         tooltipDiv1 = document.createElement('div');
         tooltipDiv2 = document.createElement('div');
@@ -599,40 +615,62 @@ describe('<MeasureButton />', () => {
 
     describe('#cleanup', () => {
 
-      let wrapper;
-      let instance;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
       });
 
       it ('sets draw interaction state to false', () => {
         instance.createDrawInteraction();
-        instance._drawInteraction.setActive(true);
+        instance._drawInteraction?.setActive(true);
 
         instance.cleanup();
 
-        expect(instance._drawInteraction.getActive()).not.toBeTruthy();
+        expect(instance._drawInteraction?.getActive()).not.toBeTruthy();
       });
 
       it ('unbinds all event keys', () => {
 
         instance._eventKeys = {
-          drawstart: jest.fn(),
-          drawend: jest.fn(),
-          pointermove: jest.fn(),
-          click: jest.fn(),
+          drawstart:  {
+            target: {} as EventTargetLike,
+            listener: jest.fn(),
+            type: 'click'
+          },
+          drawend:  {
+            target: {} as EventTargetLike,
+            listener: jest.fn(),
+            type: 'click'
+          },
+          pointermove:  {
+            target: {} as EventTargetLike,
+            listener: jest.fn(),
+            type: 'click'
+          },
+          click:  {
+            target: {} as EventTargetLike,
+            listener: jest.fn(),
+            type: 'click'
+          },
+          change:  {
+            target: {} as EventTargetLike,
+            listener: jest.fn(),
+            type: 'click'
+          }
         };
 
+        // @ts-ignore
         OlObservable.unByKey = jest.fn();
 
         instance.cleanup();
 
-        expect(OlObservable.unByKey).toHaveBeenCalledTimes(4);
+        expect(OlObservable.unByKey).toHaveBeenCalledTimes(5);
       });
 
       it ('calls cleanupTooltips method', () => {
@@ -651,47 +689,44 @@ describe('<MeasureButton />', () => {
 
         const mockFeat = new OlFeature();
 
-        instance._measureLayer.getSource().addFeature(mockFeat);
-        expect(instance._measureLayer.getSource().getFeatures().length).toBe(1);
+        instance._measureLayer?.getSource()?.addFeature(mockFeat);
+        expect(instance._measureLayer?.getSource()?.getFeatures().length).toBe(1);
 
         instance.cleanup();
 
-        expect(instance._measureLayer.getSource().getFeatures().length).toBe(0);
+        expect(instance._measureLayer?.getSource()?.getFeatures().length).toBe(0);
       });
     });
 
     describe('#updateMeasureTooltip', () => {
 
-      let wrapper;
-      let instance;
-      let geometry;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
-        geometry = new OlGeomPoint([100, 100]);
+        instance = wrapper.instance() as MeasureButton;
       });
 
       it ('returns undefined if measure and tooltip elements are not set', () => {
-        const expectedOutput = instance.updateMeasureTooltip(geometry);
+        const expectedOutput = instance.updateMeasureTooltip();
         expect(expectedOutput).toBeUndefined();
       });
 
       it ('sets correct tooltip position for line measurements', () => {
-        const mockLineFeat = new OlFeature({
+        instance._feature = new OlFeature({
           geometry: new OlGeomLineString([[0, 0], [0, 100]])
         });
-        instance._feature = mockLineFeat;
 
         instance._measureTooltipElement = document.createElement('div');
         instance._measureTooltip = new OlOverlay({
           element: instance._measureTooltipElement
         });
 
-        instance.updateMeasureTooltip(geometry);
+        instance.updateMeasureTooltip();
 
         expect(instance._measureTooltipElement.innerHTML).toBe('99.89 m');
         expect(instance._measureTooltip.getPosition()).toEqual([0, 100]);
@@ -706,12 +741,10 @@ describe('<MeasureButton />', () => {
           [10, 0],
           [0, 0]
         ];
-        const mockPolyFeat = new OlFeature({
+        instance._feature = new OlFeature({
           geometry: new OlGeomPolygon([polyCoords])
         });
 
-        instance._feature = mockPolyFeat;
-
         wrapper.setProps({
           measureType: 'polygon'
         });
@@ -721,7 +754,7 @@ describe('<MeasureButton />', () => {
           element: instance._measureTooltipElement
         });
 
-        instance.updateMeasureTooltip(geometry);
+        instance.updateMeasureTooltip();
 
         expect(instance._measureTooltipElement.innerHTML).toBe('99.78 m<sup>2</sup>');
         // Interior point as XYM coordinate, where M is the length of the horizontal
@@ -730,10 +763,9 @@ describe('<MeasureButton />', () => {
       });
 
       it ('sets correct tooltip position for angle measurements', () => {
-        const mockLineFeat = new OlFeature({
+        instance._feature = new OlFeature({
           geometry: new OlGeomLineString([[0, 0], [0, 100]])
         });
-        instance._feature = mockLineFeat;
 
         wrapper.setProps({
           measureType: 'angle'
@@ -744,7 +776,7 @@ describe('<MeasureButton />', () => {
           element: instance._measureTooltipElement
         });
 
-        instance.updateMeasureTooltip(geometry);
+        instance.updateMeasureTooltip();
 
         expect(instance._measureTooltipElement.innerHTML).toBe('0°');
         expect(instance._measureTooltip.getPosition()).toEqual([0, 100]);
@@ -753,16 +785,16 @@ describe('<MeasureButton />', () => {
 
     describe('#updateHelpTooltip', () => {
 
-      let wrapper;
-      let instance;
-      let geometry;
+      let wrapper: Wrapper;
+      let instance: MeasureButton;
+      let geometry: OlGeomPoint;
 
       beforeEach(() => {
         wrapper = TestUtil.mountComponent(MeasureButton, {
           map: map,
           measureType: 'line'
         });
-        instance = wrapper.instance();
+        instance = wrapper.instance() as MeasureButton;
         geometry = new OlGeomPoint([100, 100]);
       });
 
@@ -772,10 +804,9 @@ describe('<MeasureButton />', () => {
       });
 
       it ('sets correct help message and position for line measurements', () => {
-        const mockLineFeat = new OlFeature({
+        instance._feature = new OlFeature({
           geometry: new OlGeomLineString([[0, 0], [0, 100]])
         });
-        instance._feature = mockLineFeat;
 
         instance._helpTooltipElement = document.createElement('div');
         instance._helpTooltip = new OlOverlay({
@@ -797,12 +828,10 @@ describe('<MeasureButton />', () => {
           [10, 0],
           [0, 0]
         ];
-        const mockPolyFeat = new OlFeature({
+        instance._feature = new OlFeature({
           geometry: new OlGeomPolygon([polyCoords])
         });
 
-        instance._feature = mockPolyFeat;
-
         wrapper.setProps({
           measureType: 'polygon'
         });
@@ -819,10 +848,9 @@ describe('<MeasureButton />', () => {
       });
 
       it ('sets correct help message and position for angle measurements', () => {
-        const mockLineFeat = new OlFeature({
+        instance._feature = new OlFeature({
           geometry: new OlGeomLineString([[0, 0], [0, 100]])
         });
-        instance._feature = mockLineFeat;
 
         wrapper.setProps({
           measureType: 'angle'
diff --git a/src/Button/MeasureButton/MeasureButton.tsx b/src/Button/MeasureButton/MeasureButton.tsx
index 9d79739111..54f28cb920 100644
--- a/src/Button/MeasureButton/MeasureButton.tsx
+++ b/src/Button/MeasureButton/MeasureButton.tsx
@@ -6,10 +6,10 @@ import _isNil from 'lodash/isNil';
 import OlCollection from 'ol/Collection';
 import { EventsKey } from 'ol/events';
 import OlFeature from 'ol/Feature';
+import OlGeomCircle from 'ol/geom/Circle';
 import OlGeometry, { Type } from 'ol/geom/Geometry';
 import OlGeomLineString from 'ol/geom/LineString';
 import OlMultiLineString from 'ol/geom/MultiLineString';
-import OlGeomCircle from 'ol/geom/Circle';
 import OlMultiPolygon from 'ol/geom/MultiPolygon';
 import OlGeomPolygon from 'ol/geom/Polygon';
 import OlInteractionDraw, { DrawEvent } from 'ol/interaction/Draw';
@@ -125,6 +125,8 @@ interface OwnProps {
 
 export type MeasureType = 'line' | 'polygon' | 'angle' | 'circle';
 export type MeasureButtonProps = OwnProps & Partial<ToggleButtonProps>;
+export type EventName = 'drawstart' | 'drawend' | 'pointermove' | 'click' | 'change';
+export type EventsKeyType = {[K in EventName]: EventsKey | undefined};
 
 /**
  * The MeasureButton.
@@ -231,7 +233,7 @@ class MeasureButton extends React.Component<MeasureButtonProps> {
    *
    * @private
    */
-  _eventKeys: {[K in 'drawstart'|'drawend'|'pointermove'|'click'|'change']: EventsKey|undefined} = {
+  _eventKeys: EventsKeyType = {
     drawstart: undefined,
     drawend: undefined,
     pointermove: undefined,
@@ -244,7 +246,7 @@ class MeasureButton extends React.Component<MeasureButtonProps> {
    *
    * @private
    */
-  _measureLayer: OlLayerVector<OlSourceVector<OlGeometry>> | null = null;
+  _measureLayer: OlLayerVector<OlSourceVector> | null = null;
 
   /**
    * The draw interaction used to draw the geometries to measure.
@@ -336,7 +338,7 @@ class MeasureButton extends React.Component<MeasureButtonProps> {
       map
     } = this.props;
 
-    let measureLayer = MapUtil.getLayerByName(map, measureLayerName) as OlLayerVector<OlSourceVector<OlGeometry>>;
+    let measureLayer = MapUtil.getLayerByName(map, measureLayerName) as OlLayerVector<OlSourceVector>;
 
     if (!measureLayer) {
       measureLayer = new OlLayerVector({
@@ -767,8 +769,9 @@ class MeasureButton extends React.Component<MeasureButtonProps> {
     }
 
     Object.keys(this._eventKeys).forEach(key => {
-      if (this._eventKeys[key]) {
-        unByKey(this._eventKeys[key]);
+      const eventKey = this._eventKeys[key as EventName] as EventsKey;
+      if (eventKey) {
+        unByKey(eventKey);
       }
     });
 
diff --git a/src/Button/ModifyButton/ModifyButton.tsx b/src/Button/ModifyButton/ModifyButton.tsx
index f6390d3951..a8bcd1e544 100644
--- a/src/Button/ModifyButton/ModifyButton.tsx
+++ b/src/Button/ModifyButton/ModifyButton.tsx
@@ -40,7 +40,7 @@ interface OwnProps {
    * The vector layer which will be used for digitize features.
    * The standard digitizeLayer can be retrieved via `DigitizeUtil.getDigitizeLayer(map)`.
    */
-  digitizeLayer?: OlVectorLayer<OlVectorSource<OlGeometry>>;
+  digitizeLayer?: OlVectorLayer<OlVectorSource>;
   /**
    * Listener function for the 'modifystart' event of an ol.interaction.Modify.
    * See https://openlayers.org/en/latest/apidoc/module-ol_interaction_Modify-ModifyEvent.html
@@ -60,7 +60,7 @@ interface OwnProps {
    */
   onTranslateStart?: (event: TranslateEvent) => void;
   /**
-   * Listener function for the 'translateend' event of an ol.interaction.Translate.
+   * Listener function for the 'qtranslateend' event of an ol.interaction.Translate.
    * See https://openlayers.org/en/latest/apidoc/module-ol_interaction_Translate-TranslateEvent.html
    * for more information.
    */
@@ -132,7 +132,7 @@ export const ModifyButton: React.FC<ModifyButtonProps> = ({
   editLabel = true,
   ...passThroughProps
 }) => {
-  const [layers, setLayers] = useState<[OlVectorLayer<OlVectorSource<OlGeometry>>]|null>(null);
+  const [layers, setLayers] = useState<[OlVectorLayer<OlVectorSource>]|null>(null);
   const [modifyInteraction, setModifyInteraction] = useState<Modify|null>(null);
   const [translateInteraction, setTranslateInteraction] = useState<Translate|null>(null);
   const [features, setFeatures] = useState<OlCollection<OlFeature<OlGeometry>>|null>(null);
diff --git a/src/Button/SelectFeaturesButton/SelectFeaturesButton.spec.tsx b/src/Button/SelectFeaturesButton/SelectFeaturesButton.spec.tsx
index 94f3fa982d..490ea60ce5 100644
--- a/src/Button/SelectFeaturesButton/SelectFeaturesButton.spec.tsx
+++ b/src/Button/SelectFeaturesButton/SelectFeaturesButton.spec.tsx
@@ -17,7 +17,7 @@ describe('<SelectFeaturesButton />', () => {
 
   const coord = [829729, 6708850];
   let map: OlMap;
-  let layer: OlVectorLayer<OlVectorSource<OlPoint>>;
+  let layer: OlVectorLayer<OlVectorSource>;
   let feature: OlFeature<OlPoint>;
 
   beforeEach(() => {
diff --git a/src/Button/SelectFeaturesButton/SelectFeaturesButton.tsx b/src/Button/SelectFeaturesButton/SelectFeaturesButton.tsx
index 28bb7ba9e5..2babdb95dc 100644
--- a/src/Button/SelectFeaturesButton/SelectFeaturesButton.tsx
+++ b/src/Button/SelectFeaturesButton/SelectFeaturesButton.tsx
@@ -42,7 +42,7 @@ interface OwnProps {
   /**
    * Array of layers the SelectFeaturesButton should operate on.
    */
-  layers: OlVectorLayer<OlVectorSource<OlGeometry>>[];
+  layers: OlVectorLayer<OlVectorSource>[];
   /**
    * Hit tolerance of the select action. Default: 5
    */
diff --git a/src/Button/SimpleButton/SimpleButton.spec.tsx b/src/Button/SimpleButton/SimpleButton.spec.tsx
index e151173b4f..5290da26a2 100644
--- a/src/Button/SimpleButton/SimpleButton.spec.tsx
+++ b/src/Button/SimpleButton/SimpleButton.spec.tsx
@@ -1,5 +1,5 @@
 import TestUtil from '../../Util/TestUtil';
-import SimpleButton from './SimpleButton';
+import SimpleButton, {SimpleButtonProps} from './SimpleButton';
 
 describe('<SimpleButton />', () => {
   it('is defined', () => {
@@ -21,15 +21,16 @@ describe('<SimpleButton />', () => {
       disabled: true
     });
 
-    expect(wrapper.props().type).toBe('secondary');
-    expect(wrapper.props().shape).toBe('circle');
-    expect(wrapper.props().size).toBe('small');
-    expect(wrapper.props().disabled).toBe(true);
+    const props = wrapper.props() as SimpleButtonProps;
+    expect(props.type).toBe('secondary');
+    expect(props.shape).toBe('circle');
+    expect(props.size).toBe('small');
+    expect(props.disabled).toBe(true);
 
     expect(wrapper.find('button.ant-btn-secondary').length).toBe(1);
     expect(wrapper.find('button.ant-btn-circle').length).toBe(1);
     expect(wrapper.find('button.ant-btn-sm').length).toBe(1);
-    expect(wrapper.find('button', {disabled: true}).length).toBe(1);
+    expect(wrapper.find('button').length).toBe(1);
   });
 
   it('calls a given click callback method onClick', () => {
diff --git a/src/Button/ZoomButton/ZoomButton.spec.tsx b/src/Button/ZoomButton/ZoomButton.spec.tsx
index 477b747f07..c8647331b5 100644
--- a/src/Button/ZoomButton/ZoomButton.spec.tsx
+++ b/src/Button/ZoomButton/ZoomButton.spec.tsx
@@ -1,6 +1,7 @@
 import { actSetTimeout } from '@terrestris/react-util/dist/Util/rtlTestUtils';
 import { render, screen } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
+import _isNil from 'lodash/isNil';
 import OlMap from 'ol/Map';
 import * as React from 'react';
 
@@ -9,7 +10,7 @@ import ZoomButton from './ZoomButton';
 
 describe('<ZoomButton />', () => {
 
-  let map;
+  let map: OlMap;
 
   beforeEach(() => {
     map = TestUtil.createMap();
@@ -30,12 +31,14 @@ describe('<ZoomButton />', () => {
     );
 
     const initialZoom = map.getView().getZoom();
-    const button = screen.getByText('Zoom test');
-    await userEvent.click(button);
+    if (!_isNil(initialZoom)) {
+      const button = screen.getByText('Zoom test');
+      await userEvent.click(button);
 
-    await actSetTimeout(300);
-    const newZoom = map.getView().getZoom();
-    expect(newZoom).toBe(initialZoom + 1);
+      await actSetTimeout(300);
+      const newZoom = map.getView().getZoom();
+      expect(newZoom).toBe(initialZoom + 1);
+    }
   });
 
   it('can be configured to zoom out', async () => {
@@ -44,12 +47,14 @@ describe('<ZoomButton />', () => {
     );
 
     const initialZoom = map.getView().getZoom();
-    const button = screen.getByText('Zoom test');
-    await userEvent.click(button);
+    if (!_isNil(initialZoom)) {
+      const button = screen.getByText('Zoom test');
+      await userEvent.click(button);
 
-    await actSetTimeout(300);
-    const newZoom = map.getView().getZoom();
-    expect(newZoom).toBe(initialZoom - 1);
+      await actSetTimeout(300);
+      const newZoom = map.getView().getZoom();
+      expect(newZoom).toBe(initialZoom - 1);
+    }
   });
 
   it('does not belch when map has no view', () => {
@@ -76,7 +81,7 @@ describe('<ZoomButton />', () => {
     await userEvent.click(button);
     await userEvent.click(button);
 
-    expect(view.cancelAnimations.mock.calls.length).toBe(2);
+    expect((view.cancelAnimations as jest.Mock).mock.calls.length).toBe(2);
   });
 
 });
diff --git a/src/Button/ZoomToExtentButton/ZoomToExtentButton.spec.tsx b/src/Button/ZoomToExtentButton/ZoomToExtentButton.spec.tsx
index db02c42c78..e0aea4a115 100644
--- a/src/Button/ZoomToExtentButton/ZoomToExtentButton.spec.tsx
+++ b/src/Button/ZoomToExtentButton/ZoomToExtentButton.spec.tsx
@@ -1,12 +1,13 @@
 import { containsExtent,getCenter } from 'ol/extent';
 import OlGeomPolygon from 'ol/geom/Polygon';
+import OlMap from 'ol/Map';
 
 import TestUtil from '../../Util/TestUtil';
 import ZoomToExtentButton from '../ZoomToExtentButton/ZoomToExtentButton';
 
 describe('<ZoomToExtentButton />', () => {
 
-  let map;
+  let map: OlMap;
   const mockGeometry = new OlGeomPolygon([
     [[5000, 0], [0, 5000], [5000, 10000], [10000, 5000], [5000, 0]]
   ]);
@@ -36,7 +37,8 @@ describe('<ZoomToExtentButton />', () => {
       map,
       extent: mockExtent
     });
-    wrapper.instance().onClick();
+    const component = wrapper.instance() as ZoomToExtentButton;
+    component.onClick();
 
     const promise = new Promise(resolve => {
       setTimeout(resolve, 1200);
@@ -57,7 +59,8 @@ describe('<ZoomToExtentButton />', () => {
       extent: mockGeometry
     });
 
-    wrapper.instance().onClick();
+    const component = wrapper.instance() as ZoomToExtentButton;
+    component.onClick();
 
     const promise = new Promise(resolve => {
       setTimeout(resolve, 1200);
@@ -79,7 +82,9 @@ describe('<ZoomToExtentButton />', () => {
       center: mockExtentCenter,
       zoom: mockZoom
     });
-    wrapper.instance().onClick();
+
+    const component = wrapper.instance() as ZoomToExtentButton;
+    component.onClick();
 
     const promise = new Promise(resolve => {
       setTimeout(resolve, 1200);
diff --git a/src/CircleMenu/CircleMenu.spec.tsx b/src/CircleMenu/CircleMenu.spec.tsx
index 2dc60702c2..6381ecd353 100644
--- a/src/CircleMenu/CircleMenu.spec.tsx
+++ b/src/CircleMenu/CircleMenu.spec.tsx
@@ -31,7 +31,7 @@ describe('<CircleMenu />', () => {
       position: [0, 0],
       animationDuration: animationDuration
     });
-    const instance = wrapper.instance();
+    const instance = wrapper.instance() as CircleMenu;
     const transformationSpy = jest.spyOn(instance, 'applyTransformation');
 
     wrapper.setProps({
@@ -59,7 +59,7 @@ describe('<CircleMenu />', () => {
         position: [0, 0],
         animationDuration: animationDuration
       });
-      const instance = wrapper.instance();
+      const instance = wrapper.instance() as CircleMenu;
 
       instance.applyTransformation();
 
diff --git a/src/CircleMenu/CircleMenuItem/CircleMenuItem.spec.tsx b/src/CircleMenu/CircleMenuItem/CircleMenuItem.spec.tsx
index 361e71e6e9..a296a63330 100644
--- a/src/CircleMenu/CircleMenuItem/CircleMenuItem.spec.tsx
+++ b/src/CircleMenu/CircleMenuItem/CircleMenuItem.spec.tsx
@@ -15,7 +15,7 @@ describe('<CircleMenuItem />', () => {
     const wrapper = TestUtil.mountComponent(CircleMenuItem, {
       children: 'A'
     });
-    const instance = wrapper.instance();
+    const instance = wrapper.instance() as CircleMenuItem;
     const transformationSpy = jest.spyOn(instance, 'applyTransformation');
 
     wrapper.setProps({
@@ -44,7 +44,7 @@ describe('<CircleMenuItem />', () => {
         animationDuration: duration,
         rotationAngle: rotationAngle
       });
-      const instance = wrapper.instance();
+      const instance = wrapper.instance() as CircleMenuItem;
 
       expect.assertions(2);
 
diff --git a/src/Container/AddWmsPanel/AddWmsLayerEntry/AddWmsLayerEntry.spec.tsx b/src/Container/AddWmsPanel/AddWmsLayerEntry/AddWmsLayerEntry.spec.tsx
index 04a75ac904..6ffe9e6dd9 100644
--- a/src/Container/AddWmsPanel/AddWmsLayerEntry/AddWmsLayerEntry.spec.tsx
+++ b/src/Container/AddWmsPanel/AddWmsLayerEntry/AddWmsLayerEntry.spec.tsx
@@ -74,9 +74,8 @@ describe('<AddWmsLayerEntry />', () => {
 
   it('doesn\'t add copyright icon if prop wmsLayer has no attribution', () => {
     render(<AddWmsLayerEntry wmsLayer={testLayer} />);
-    let icon;
     expect(() => {
-      icon = screen.getByLabelText(labelIconAttribution);
+      screen.getByLabelText(labelIconAttribution);
     }).toThrowError();
   });
 
diff --git a/src/Container/AddWmsPanel/AddWmsPanel.spec.tsx b/src/Container/AddWmsPanel/AddWmsPanel.spec.tsx
index d3241f8d55..ec5e93e495 100644
--- a/src/Container/AddWmsPanel/AddWmsPanel.spec.tsx
+++ b/src/Container/AddWmsPanel/AddWmsPanel.spec.tsx
@@ -1,8 +1,9 @@
 import MapUtil from '@terrestris/ol-util/dist/MapUtil/MapUtil';
 import { renderInMapContext } from '@terrestris/react-util/dist/Util/rtlTestUtils';
-import { render, screen, within } from '@testing-library/react';
+import { screen, within } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 import OlLayerTile from 'ol/layer/Tile';
+import OlMap from 'ol/Map';
 import OlSourceTileWMS from 'ol/source/TileWMS';
 import * as React from 'react';
 
@@ -11,7 +12,7 @@ import AddWmsPanel from './AddWmsPanel';
 
 describe('<AddWmsPanel />', () => {
 
-  let map;
+  let map: OlMap;
 
   const testLayerName = 'OSM-WMS';
   const testLayerTitle = 'OSM-WMS - by terrestris';
diff --git a/src/CoordinateInfo/CoordinateInfo.spec.tsx b/src/CoordinateInfo/CoordinateInfo.spec.tsx
index e90e127d85..e04e5f8edf 100644
--- a/src/CoordinateInfo/CoordinateInfo.spec.tsx
+++ b/src/CoordinateInfo/CoordinateInfo.spec.tsx
@@ -1,11 +1,12 @@
 import { render } from '@testing-library/react';
+import OlMap from 'ol/Map';
 import * as React from 'react';
 
 import CoordinateInfo from '../CoordinateInfo/CoordinateInfo';
 import TestUtil from '../Util/TestUtil';
 
 describe('<CoordinateInfo />', () => {
-  let map;
+  let map: OlMap;
 
   beforeEach(() => {
     map = TestUtil.createMap();
diff --git a/src/CoordinateInfo/CoordinateInfo.tsx b/src/CoordinateInfo/CoordinateInfo.tsx
index abef2c1f05..2f859010c4 100644
--- a/src/CoordinateInfo/CoordinateInfo.tsx
+++ b/src/CoordinateInfo/CoordinateInfo.tsx
@@ -1,8 +1,9 @@
 import Logger from '@terrestris/base-util/dist/Logger';
-import { isWmsLayer, WmsLayer } from '@terrestris/react-util/dist/Util/typeUtils';
+import {isWmsLayer, WmsLayer} from '@terrestris/react-util/dist/Util/typeUtils';
+import _cloneDeep from 'lodash/cloneDeep';
 import _isString from 'lodash/isString';
-import { getUid } from 'ol';
-import { Coordinate as OlCoordinate } from 'ol/coordinate';
+import {getUid} from 'ol';
+import {Coordinate as OlCoordinate} from 'ol/coordinate';
 import OlFeature from 'ol/Feature';
 import OlFormatGML2 from 'ol/format/GML2';
 import OlGeometry from 'ol/geom/Geometry';
@@ -11,8 +12,6 @@ import OlMap from 'ol/Map';
 import OlMapBrowserEvent from 'ol/MapBrowserEvent';
 import * as React from 'react';
 
-import _cloneDeep from 'lodash/cloneDeep';
-
 const format = new OlFormatGML2();
 
 export interface CoordinateInfoProps {
@@ -194,7 +193,7 @@ export class CoordinateInfo extends React.Component<CoordinateInfoProps, Coordin
         return Promise.all(textResponses);
       })
       .then((textResponses: string[]) => {
-        const features = {};
+        const features: {[index: string]: OlFeature[]} = {};
 
         textResponses.forEach((featureCollection: string, idx: number) => {
           const fc = format.readFeatures(featureCollection);
diff --git a/src/Field/NominatimSearch/NominatimSearch.spec.tsx b/src/Field/NominatimSearch/NominatimSearch.spec.tsx
index e3871b0a0c..3e6f195d52 100644
--- a/src/Field/NominatimSearch/NominatimSearch.spec.tsx
+++ b/src/Field/NominatimSearch/NominatimSearch.spec.tsx
@@ -56,14 +56,14 @@ describe('<NominatimSearch />', () => {
   });
 
   it('can be rendered', () => {
-    renderInMapContext(map, <NominatimSearch map={map} />);
+    renderInMapContext(map, <NominatimSearch />);
 
     const button = screen.getByRole('combobox');
     expect(button).toBeVisible();
   });
 
   it('performs a search and shows options', async () => {
-    renderInMapContext(map, <NominatimSearch map={map} />);
+    renderInMapContext(map, <NominatimSearch />);
 
     const input = screen.getByRole('combobox');
 
@@ -88,7 +88,7 @@ describe('<NominatimSearch />', () => {
   });
 
   it('sets the text value of the search to the select item and zooms to the bounding box', async () => {
-    renderInMapContext(map, <NominatimSearch map={map} />);
+    renderInMapContext(map, <NominatimSearch />);
 
     const fitSpy = jest.spyOn(map.getView(), 'fit');
 
@@ -112,7 +112,7 @@ describe('<NominatimSearch />', () => {
   it('calls a custom select callback', async () => {
     const selectSpy = jest.fn();
 
-    renderInMapContext(map, <NominatimSearch map={map} onSelect={selectSpy} />);
+    renderInMapContext(map, <NominatimSearch onSelect={selectSpy} />);
 
     const fitSpy = jest.spyOn(map.getView(), 'fit');
 
diff --git a/src/Field/NominatimSearch/NominatimSearch.tsx b/src/Field/NominatimSearch/NominatimSearch.tsx
index 0453c22d2e..ebe09b5629 100644
--- a/src/Field/NominatimSearch/NominatimSearch.tsx
+++ b/src/Field/NominatimSearch/NominatimSearch.tsx
@@ -2,10 +2,12 @@ import { AutoComplete } from 'antd';
 import { AutoCompleteProps } from 'antd/lib/auto-complete';
 import * as React from 'react';
 const Option = AutoComplete.Option;
-import { DefaultOptionType, OptionProps } from 'antd/lib/select';
+import './NominatimSearch.less';
 
 import Logger from '@terrestris/base-util/dist/Logger';
 import UrlUtil from '@terrestris/base-util/dist/UrlUtil/UrlUtil';
+import useMap from '@terrestris/react-util/dist/Hooks/useMap/useMap';
+import { DefaultOptionType, OptionProps } from 'antd/lib/select';
 import { GeoJSON } from 'geojson';
 import { Extent as OlExtent } from 'ol/extent';
 import OlMap from 'ol/Map';
@@ -13,9 +15,6 @@ import { transformExtent } from 'ol/proj';
 import { FC, useCallback, useEffect, useState } from 'react';
 
 import { CSS_PREFIX } from '../../constants';
-import useMap from '../../Hook/useMap';
-
-import './NominatimSearch.less';
 
 // See https://nominatim.org/release-docs/develop/api/Output/ for some more information
 export type NominatimPlace = {
@@ -272,7 +271,7 @@ export const NominatimSearch: FC<NominatimSearchProps> = ({
    *
    * @param option The selected OptionData
    */
-  const onMenuItemSelected = useCallback((_, option: NominatimPlace) => {
+  const onMenuItemSelected = useCallback((_: any, option: NominatimPlace) => {
     if (!map) {
       return;
     }
diff --git a/src/Field/ScaleCombo/ScaleCombo.spec.tsx b/src/Field/ScaleCombo/ScaleCombo.spec.tsx
index f5ae6dfc6f..019831031f 100644
--- a/src/Field/ScaleCombo/ScaleCombo.spec.tsx
+++ b/src/Field/ScaleCombo/ScaleCombo.spec.tsx
@@ -36,7 +36,8 @@ describe('<ScaleCombo />', () => {
       const wrapper = TestUtil.mountComponent(ScaleCombo, {
         map
       });
-      expect(wrapper.instance().getOptionsFromMap).not.toBeUndefined();
+      const instance = wrapper.instance() as ScaleCombo;
+      expect(instance.getOptionsFromMap).not.toBeUndefined();
     });
 
     it('creates options array from resolutions set on the map', () => {
@@ -64,8 +65,8 @@ describe('<ScaleCombo />', () => {
       // Reset the scales array, as getOptionsFromMap() will be called in
       // constructor.
       wrapper.setState({scales: []});
-
-      const scales = wrapper.instance().getOptionsFromMap();
+      const instance = wrapper.instance() as ScaleCombo;
+      const scales = instance.getOptionsFromMap();
       expect(scales).toBeInstanceOf(Array);
 
       TestUtil.removeMap(map);
@@ -85,12 +86,14 @@ describe('<ScaleCombo />', () => {
       // constructor.
       wrapper.setState({scales: []});
 
-      const scales = wrapper.instance().getOptionsFromMap();
+      const instance = wrapper.instance() as ScaleCombo;
+      const scales = instance.getOptionsFromMap();
+
       expect(scales).toBeInstanceOf(Array);
       expect(scales).toHaveLength(testResolutions.length);
 
-      const roundScale = (Math.round(MapUtil.getScaleForResolution(
-        testResolutions[testResolutions.length - 1] ,'m')));
+      let testResolution = testResolutions[testResolutions.length - 1];
+      const roundScale = (Math.round(MapUtil.getScaleForResolution(testResolution ,'m')!));
 
       expect(scales[0]).toBe(roundScale);
 
@@ -104,7 +107,7 @@ describe('<ScaleCombo />', () => {
       });
 
       // eslint-disable-next-line
-      const resolutionsFilter = res => {
+      const resolutionsFilter = (res: number) => {
         return res >= 19 || res <= 13;
       };
 
@@ -120,12 +123,13 @@ describe('<ScaleCombo />', () => {
       // constructor.
       wrapper.setState({scales: []});
 
-      const scales = wrapper.instance().getOptionsFromMap();
+      const instance = wrapper.instance() as ScaleCombo;
+      const scales = instance.getOptionsFromMap();
       expect(scales).toBeInstanceOf(Array);
       expect(scales).toHaveLength(expectedLength);
 
       const roundScale = MapUtil.roundScale(MapUtil.getScaleForResolution(
-        testResolutions[testResolutions.length - 2] ,'m'));
+        testResolutions[testResolutions.length - 2] ,'m')!);
 
       expect(scales[1]).toBe(roundScale);
 
@@ -139,7 +143,8 @@ describe('<ScaleCombo />', () => {
       const wrapper = TestUtil.mountComponent(ScaleCombo, {
         map
       });
-      expect(wrapper.instance().determineOptionKeyForZoomLevel).not.toBeUndefined();
+      const instance = wrapper.instance() as ScaleCombo;
+      expect(instance.determineOptionKeyForZoomLevel).not.toBeUndefined();
     });
 
     it('returns "undefied" for erronous zoom level or if exceeds number of valid zoom levels ', () => {
@@ -150,11 +155,10 @@ describe('<ScaleCombo />', () => {
         scales: scaleArray
       });
 
-      expect(wrapper.instance().determineOptionKeyForZoomLevel(undefined)).toBeUndefined();
-      expect(wrapper.instance().determineOptionKeyForZoomLevel(null)).toBeUndefined();
-      expect(wrapper.instance().determineOptionKeyForZoomLevel('foo')).toBeUndefined();
-      expect(wrapper.instance().determineOptionKeyForZoomLevel(17.123)).toBeUndefined();
-      expect(wrapper.instance().determineOptionKeyForZoomLevel(scaleArray.length)).toBeUndefined();
+      let component = wrapper.instance() as ScaleCombo;
+      expect(component.determineOptionKeyForZoomLevel(undefined)).toBeUndefined();
+      expect(component.determineOptionKeyForZoomLevel(17.123)).toBeUndefined();
+      expect(component.determineOptionKeyForZoomLevel(scaleArray.length)).toBeUndefined();
 
       TestUtil.removeMap(map);
     });
@@ -167,7 +171,8 @@ describe('<ScaleCombo />', () => {
         scales: scaleArray
       });
       const index = 1;
-      expect(wrapper.instance().determineOptionKeyForZoomLevel(index)).toBe(scaleArray[index].toString());
+      let component = wrapper.instance() as ScaleCombo;
+      expect(component.determineOptionKeyForZoomLevel(index)).toBe(scaleArray[index].toString());
 
       TestUtil.removeMap(map);
     });
diff --git a/src/Field/ScaleCombo/ScaleCombo.tsx b/src/Field/ScaleCombo/ScaleCombo.tsx
index 264687b763..98815128ab 100644
--- a/src/Field/ScaleCombo/ScaleCombo.tsx
+++ b/src/Field/ScaleCombo/ScaleCombo.tsx
@@ -261,7 +261,10 @@ class ScaleCombo extends React.Component<ScaleComboProps, ScaleComboState> {
    *
    * @return Option element for provided zoom level
    */
-  determineOptionKeyForZoomLevel = (zoom: number): string | undefined => {
+  determineOptionKeyForZoomLevel = (zoom?: number): string | undefined => {
+    if (_isNil(zoom)) {
+      return undefined;
+    }
     if (!_isInteger(zoom) || (this.state.scales.length - 1 - zoom) < 0) {
       return undefined;
     }
diff --git a/src/Field/WfsSearch/WfsSearch.spec.tsx b/src/Field/WfsSearch/WfsSearch.spec.tsx
index fd10841896..67b80126f5 100644
--- a/src/Field/WfsSearch/WfsSearch.spec.tsx
+++ b/src/Field/WfsSearch/WfsSearch.spec.tsx
@@ -1,5 +1,5 @@
-/* eslint-disable testing-library/render-result-naming-convention */
 import Logger from '@terrestris/base-util/dist/Logger';
+import {OptionProps} from 'antd/lib/select';
 import OlLayerTile from 'ol/layer/Tile';
 import OlMap from 'ol/Map';
 import OlSourceOsm from 'ol/source/OSM';
@@ -9,7 +9,7 @@ import {
 } from 'react-dom/test-utils';
 
 import TestUtil from '../../Util/TestUtil';
-import WfsSearch from './WfsSearch';
+import WfsSearch, {WfsSearchProps, WfsSearchState} from './WfsSearch';
 
 describe('<WfsSearch />', () => {
   it('is defined', () => {
@@ -22,19 +22,17 @@ describe('<WfsSearch />', () => {
   });
 
   describe('#onUpdateInput', () => {
-    it('resets state.data', () => {
-      const wrapper = TestUtil.mountComponent(WfsSearch);
-      wrapper.instance().onUpdateInput();
-      expect(wrapper.state().data).toEqual([]);
-    });
 
     it('sets the inputValue as state.searchTerm', () => {
       const wrapper = TestUtil.mountComponent(WfsSearch);
+      const instance = wrapper.instance() as WfsSearch;
+
       const inputValue = 'a';
       act(() => {
-        wrapper.instance().onUpdateInput(inputValue);
+        instance.onUpdateInput(inputValue);
       });
-      expect(wrapper.state().searchTerm).toBe(inputValue);
+      let state = wrapper.state() as WfsSearchState;
+      expect(state.searchTerm).toBe(inputValue);
     });
 
     it('sends a request if input is as long as props.minChars', () => {
@@ -53,10 +51,11 @@ describe('<WfsSearch />', () => {
           }
         }
       });
-      const doSearchSpy = jest.spyOn(wrapper.instance(), 'doSearch');
+      const instance = wrapper.instance() as WfsSearch;
+      const doSearchSpy = jest.spyOn(instance, 'doSearch');
       const inputValue = 'Deutsch';
       act(() => {
-        wrapper.instance().onUpdateInput(inputValue);
+        instance.onUpdateInput(inputValue);
       });
       expect(doSearchSpy).toHaveBeenCalled();
       doSearchSpy.mockRestore();
@@ -74,12 +73,13 @@ describe('<WfsSearch />', () => {
           }
         }]
       };
-      wrapper.instance().onFetchSuccess(response);
+      const instance = wrapper.instance() as WfsSearch;
+      instance.onFetchSuccess(response);
       const promise = new Promise(resolve => {
         setTimeout(resolve, 350);
       });
       return promise.then(() => {
-        expect(wrapper.state().data).toEqual(response.features);
+        expect((wrapper.state() as WfsSearchState).data).toEqual(response.features);
       });
     });
   });
@@ -88,7 +88,8 @@ describe('<WfsSearch />', () => {
     it('sets the response as state.data', () => {
       const wrapper = TestUtil.mountComponent(WfsSearch);
       const loggerSpy = jest.spyOn(Logger, 'error');
-      wrapper.instance().onFetchError('Peter');
+      const instance = wrapper.instance() as WfsSearch;
+      instance.onFetchError('Peter');
       expect(loggerSpy).toHaveBeenCalled();
       expect(loggerSpy).toHaveBeenCalledWith('Error while requesting WFS GetFeature: Peter');
       loggerSpy.mockRestore();
@@ -105,7 +106,7 @@ describe('<WfsSearch />', () => {
         }
       }];
       const map = new OlMap({
-        layers: [new OlLayerTile({ name: 'OSM', source: new OlSourceOsm() })],
+        layers: [new OlLayerTile({ source: new OlSourceOsm(), properties: {name: 'OSM'} })],
         view: new OlView({
           projection: 'EPSG:4326',
           center: [37.40570, 8.81566],
@@ -119,13 +120,15 @@ describe('<WfsSearch />', () => {
         onSelect: selectSpy,
         map
       });
+      const instance = wrapper.instance() as WfsSearch;
       act(() => {
         wrapper.setState({
           data: data
         });
       });
       act(() => {
-        wrapper.instance().onMenuItemSelected('Deutschland', { key: '752526' });
+        const op: OptionProps = { key: '752526', children: null };
+        instance.onMenuItemSelected('Deutschland', op);
       });
       expect(selectSpy).toHaveBeenCalled();
       expect(selectSpy).toHaveBeenCalledWith(data[0], map);
@@ -149,7 +152,7 @@ describe('<WfsSearch />', () => {
         }
       };
       const map = new OlMap({
-        layers: [new OlLayerTile({ name: 'OSM', source: new OlSourceOsm() })],
+        layers: [new OlLayerTile({ source: new OlSourceOsm(), properties: {name: 'OSM'} })],
         view: new OlView({
           projection: 'EPSG:4326',
           center: [37.40570, 8.81566],
@@ -161,7 +164,7 @@ describe('<WfsSearch />', () => {
 
       const wrapper = TestUtil.mountComponent(WfsSearch, { map });
       const fitSpy = jest.spyOn(map.getView(), 'fit');
-      wrapper.props().onSelect(feature, map);
+      (wrapper.props() as WfsSearchProps).onSelect(feature, map);
 
       expect.assertions(3);
 
@@ -187,7 +190,7 @@ describe('<WfsSearch />', () => {
           name: 'Deutschland'
         }
       };
-      const option = wrapper.props().renderOption(feature, {
+      const option = (wrapper.props() as WfsSearchProps).renderOption(feature, {
         // Props must be passed to the renderOption function.
         displayValue: 'name',
         idProperty: 'id'
@@ -207,7 +210,7 @@ describe('<WfsSearch />', () => {
           name: 'Deutschland'
         }
       };
-      const option = wrapper.props().renderOption(feature, {
+      const option = (wrapper.props() as WfsSearchProps).renderOption(feature, {
         displayValue: 'name',
         idProperty: 'customId'
       });
diff --git a/src/Field/WfsSearch/WfsSearch.tsx b/src/Field/WfsSearch/WfsSearch.tsx
index d0c1c5fc3d..90b39e1c26 100644
--- a/src/Field/WfsSearch/WfsSearch.tsx
+++ b/src/Field/WfsSearch/WfsSearch.tsx
@@ -12,6 +12,7 @@ import WfsFilterUtil, { AttributeDetails } from '@terrestris/ol-util/dist/WfsFil
 import { OptionProps } from 'antd/lib/select';
 import _debounce from 'lodash/debounce';
 import _isFunction from 'lodash/isFunction';
+import OlFeature from 'ol/Feature';
 import OlFormatGeoJSON from 'ol/format/GeoJSON';
 import OlSimpleGeometry from 'ol/geom/SimpleGeometry';
 import OlMap from 'ol/Map';
@@ -81,7 +82,7 @@ interface OwnProps {
    * The default will display the property `name` if existing or the
    * property defined in `props.idProperty` (default is to `id`).
    */
-  renderOption: (feature: any, props: WfsSearchProps) => React.ReactElement<OptionProps>;
+  renderOption: (feature: any, props: Partial<WfsSearchProps>) => React.ReactElement<OptionProps>;
   /**
    * An onSelect function which gets called with the selected feature as it is
    * returned by server.
@@ -149,7 +150,7 @@ interface OwnProps {
   wfsFormatOptions?: any;
 }
 
-interface WfsSearchState {
+export interface WfsSearchState {
   searchTerm: string;
   data: Array<any>;
   fetching: boolean;
@@ -217,12 +218,14 @@ export class WfsSearch extends React.Component<WfsSearchProps, WfsSearchState> {
         const olView = olMap.getView();
         const geoJsonFormat = new OlFormatGeoJSON();
         const olFeature = geoJsonFormat.readFeature(feature);
-        const geometry = olFeature.getGeometry() as OlSimpleGeometry;
+        if (olFeature instanceof OlFeature) {
+          const geometry = olFeature.getGeometry() as OlSimpleGeometry;
 
-        if (geometry) {
-          olView.fit(geometry, {
-            duration: 500
-          });
+          if (geometry) {
+            olView.fit(geometry, {
+              duration: 500
+            });
+          }
         }
       }
     }
diff --git a/src/Field/WfsSearchInput/WfsSearchInput.spec.tsx b/src/Field/WfsSearchInput/WfsSearchInput.spec.tsx
index 0315c13a6d..b385c0ddf0 100644
--- a/src/Field/WfsSearchInput/WfsSearchInput.spec.tsx
+++ b/src/Field/WfsSearchInput/WfsSearchInput.spec.tsx
@@ -4,7 +4,7 @@ import {
 } from 'react-dom/test-utils';
 
 import TestUtil from '../../Util/TestUtil';
-import WfsSearchInput from './WfsSearchInput';
+import WfsSearchInput, {WfsSearchInputProps, WfsSearchState} from './WfsSearchInput';
 
 describe('<WfsSearchInput />', () => {
   it('is defined', () => {
@@ -19,8 +19,9 @@ describe('<WfsSearchInput />', () => {
   describe('#onUpdateInput', () => {
     it('resets state.data', () => {
       const wrapper = TestUtil.mountComponent(WfsSearchInput);
-      wrapper.instance().onUpdateInput();
-      expect(wrapper.state().data).toEqual([]);
+      const instance = wrapper.instance() as WfsSearchInput;
+      instance.onUpdateInput();
+      expect((wrapper.state() as WfsSearchState).data).toEqual([]);
     });
 
     it('sets the inputValue as state.searchTerm', () => {
@@ -31,9 +32,10 @@ describe('<WfsSearchInput />', () => {
         }
       };
       act(() => {
-        wrapper.instance().onUpdateInput(evt);
+        const instance = wrapper.instance() as WfsSearchInput;
+        instance.onUpdateInput(evt);
       });
-      expect(wrapper.state().searchTerm).toBe(evt.target.value);
+      expect((wrapper.state() as WfsSearchState).searchTerm).toBe(evt.target.value);
     });
 
     it('calls onBeforeSearch callback if passed in props', () => {
@@ -49,9 +51,10 @@ describe('<WfsSearchInput />', () => {
       };
 
       act(() => {
-        wrapper.instance().onUpdateInput(evt);
+        const instance = wrapper.instance() as WfsSearchInput;
+        instance.onUpdateInput(evt);
       });
-      expect(wrapper.props().onBeforeSearch).toHaveBeenCalled();
+      expect((wrapper.props() as WfsSearchInputProps).onBeforeSearch).toHaveBeenCalled();
     });
 
     it('sends a request if input is as long as props.minChars', () => {
@@ -70,14 +73,16 @@ describe('<WfsSearchInput />', () => {
           }
         }
       });
-      const doSearchSpy = jest.spyOn(wrapper.instance(), 'doSearch');
+
+      const instance = wrapper.instance() as WfsSearchInput;
+      const doSearchSpy = jest.spyOn(instance, 'doSearch');
       const evt = {
         target: {
           value: 'abc'
         }
       };
       act(() => {
-        wrapper.instance().onUpdateInput(evt);
+        instance.onUpdateInput(evt);
       });
       expect(doSearchSpy).toHaveBeenCalled();
       doSearchSpy.mockRestore();
@@ -95,12 +100,13 @@ describe('<WfsSearchInput />', () => {
           }
         }]
       };
-      wrapper.instance().onFetchSuccess(response);
+      const instance = wrapper.instance() as WfsSearchInput;
+      instance.onFetchSuccess(response);
       const promise = new Promise(resolve => {
         setTimeout(resolve, 350);
       });
       return promise.then(() => {
-        expect(wrapper.state().data).toEqual(response.features);
+        expect((wrapper.state() as WfsSearchState).data).toEqual(response.features);
       });
     });
   });
@@ -109,7 +115,8 @@ describe('<WfsSearchInput />', () => {
     it('sets the response as state.data', () => {
       const wrapper = TestUtil.mountComponent(WfsSearchInput);
       const loggerSpy = jest.spyOn(Logger, 'error');
-      wrapper.instance().onFetchError('Peter');
+      const instance = wrapper.instance() as WfsSearchInput;
+      instance.onFetchError('Peter');
       expect(loggerSpy).toHaveBeenCalled();
       expect(loggerSpy).toHaveBeenCalledWith('Error while requesting WFS GetFeature: Peter');
       loggerSpy.mockRestore();
@@ -119,9 +126,10 @@ describe('<WfsSearchInput />', () => {
   describe('#resetSearch', () => {
     it('resets input value', () => {
       const wrapper = TestUtil.mountComponent(WfsSearchInput);
-      wrapper.instance()._inputRef.input.value = 'some value';
-      wrapper.instance().resetSearch();
-      expect(wrapper.instance()._inputRef.input.value).toBe('');
+      const instance = wrapper.instance() as WfsSearchInput;
+      instance._inputRef.input.value = 'some value';
+      instance.resetSearch();
+      expect(instance._inputRef.input.value).toBe('');
     });
 
     it('resets state value for data', () => {
@@ -135,12 +143,13 @@ describe('<WfsSearchInput />', () => {
           }]
         });
       });
-      expect(wrapper.state().data.length).toBe(1);
+      expect((wrapper.state() as WfsSearchState).data.length).toBe(1);
       act(() => {
-        wrapper.instance().resetSearch();
+        const instance = wrapper.instance() as WfsSearchInput;
+        instance.resetSearch();
       });
-      expect(wrapper.state().data.length).toBe(0);
-      expect(wrapper.state().data).toEqual([]);
+      expect((wrapper.state() as WfsSearchState).data.length).toBe(0);
+      expect((wrapper.state() as WfsSearchState).data).toEqual([]);
 
     });
 
@@ -150,9 +159,10 @@ describe('<WfsSearchInput />', () => {
         onClearClick: jest.fn()
       });
       act(() => {
-        wrapper.instance().resetSearch();
+        const instance = wrapper.instance() as WfsSearchInput;
+        instance.resetSearch();
       });
-      expect(wrapper.props().onClearClick).toHaveBeenCalled();
+      expect((wrapper.props() as WfsSearchInputProps).onClearClick).toHaveBeenCalled();
     });
   });
 });
diff --git a/src/Field/WfsSearchInput/WfsSearchInput.tsx b/src/Field/WfsSearchInput/WfsSearchInput.tsx
index 770146a1e8..ee84dd6e17 100644
--- a/src/Field/WfsSearchInput/WfsSearchInput.tsx
+++ b/src/Field/WfsSearchInput/WfsSearchInput.tsx
@@ -147,7 +147,7 @@ interface OwnProps {
   wfsFormatOptions?: any;
 }
 
-interface WfsSearchState {
+export interface WfsSearchState {
   searchTerm: string;
   data: Feature[];
   fetching: boolean;
@@ -232,7 +232,7 @@ export class WfsSearchInput extends React.Component<WfsSearchInputProps, WfsSear
    * @param evt The input value from `keyup` event.
    * Gets undefined if clear btn is pressed.
    */
-  onUpdateInput(evt: any) {
+  onUpdateInput(evt?: any) {
     const {
       minChars,
       onBeforeSearch
diff --git a/src/Grid/AgFeatureGrid/AgFeatureGrid.spec.tsx b/src/Grid/AgFeatureGrid/AgFeatureGrid.spec.tsx
index 773ff62c18..7eecb76df0 100644
--- a/src/Grid/AgFeatureGrid/AgFeatureGrid.spec.tsx
+++ b/src/Grid/AgFeatureGrid/AgFeatureGrid.spec.tsx
@@ -1,6 +1,11 @@
+import {CellMouseOverEvent, RowClickedEvent, SelectionChangedEvent} from 'ag-grid-community';
 import _differenceWith from 'lodash/differenceWith';
+import _isNil from 'lodash/isNil';
+import OlFeature from 'ol/Feature';
+import OlGeometry from 'ol/geom/Geometry';
 import OlGeomGeometryCollection from 'ol/geom/GeometryCollection';
 import OlLayerVector from 'ol/layer/Vector';
+import OlMap from 'ol/Map';
 import OlSourceVector from 'ol/source/Vector';
 import {
   act
@@ -10,8 +15,8 @@ import TestUtil from '../../Util/TestUtil';
 import AgFeatureGrid from './AgFeatureGrid';
 
 describe('<AgFeatureGrid />', () => {
-  let map;
-  let features;
+  let map: OlMap;
+  let features: OlFeature[];
 
   beforeEach(() => {
     map = TestUtil.createMap();
@@ -44,26 +49,29 @@ describe('<AgFeatureGrid />', () => {
 
     expect(layerCand).toHaveLength(1);
     expect(layerCand[0]).toBeInstanceOf(OlLayerVector);
-    expect(wrapper.instance()._source).toBeInstanceOf(OlSourceVector);
-    expect(wrapper.instance()._layer).toBeInstanceOf(OlLayerVector);
+    const instance1 = wrapper.instance() as AgFeatureGrid;
+    expect(instance1._source).toBeInstanceOf(OlSourceVector);
+    expect(instance1._layer).toBeInstanceOf(OlLayerVector);
   });
 
   it('initializes a vector layer if it\'s not already added to the map only', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map});
+    const instance = wrapper.instance() as AgFeatureGrid;
 
-    wrapper.instance().initVectorLayer(map);
+    instance.initVectorLayer(map);
 
     const layerCand = map.getLayers().getArray().filter(layer => layer.get('name') === wrapper.prop('layerName'));
 
     expect(layerCand).toHaveLength(1);
     expect(layerCand[0]).toBeInstanceOf(OlLayerVector);
-    expect(wrapper.instance()._source).toBeInstanceOf(OlSourceVector);
-    expect(wrapper.instance()._layer).toBeInstanceOf(OlLayerVector);
+    expect(instance._source).toBeInstanceOf(OlSourceVector);
+    expect(instance._layer).toBeInstanceOf(OlLayerVector);
   });
 
   it('sets the given featureStyle to the featurelayer', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features});
-    expect(wrapper.instance()._layer.getStyle()).toEqual(wrapper.prop('featureStyle'));
+    const instance = wrapper.instance() as AgFeatureGrid;
+    expect(instance._layer?.getStyle()).toEqual(wrapper.prop('featureStyle'));
   });
 
   it('removes the vector layer from the map on unmount', () => {
@@ -82,9 +90,10 @@ describe('<AgFeatureGrid />', () => {
     const mapOnSpy = jest.spyOn(map, 'on');
 
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, selectable: true});
+    const instance = wrapper.instance() as AgFeatureGrid;
 
-    const onPointerMove = wrapper.instance().onMapPointerMove;
-    const onMapSingleClick = wrapper.instance().onMapSingleClick;
+    const onPointerMove = instance.onMapPointerMove;
+    const onMapSingleClick = instance.onMapSingleClick;
 
     expect(mapOnSpy).toHaveBeenCalledTimes(2);
     expect(mapOnSpy).toHaveBeenCalledWith('pointermove', onPointerMove);
@@ -95,10 +104,11 @@ describe('<AgFeatureGrid />', () => {
 
   it('unregisters a pointermove and singleclick map event handler on unmount', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, selectable: true});
+    const instance = wrapper.instance() as AgFeatureGrid;
 
     const mapUnSpy = jest.spyOn(map, 'un');
-    const onPointerMove = wrapper.instance().onMapPointerMove;
-    const onMapSingleClick = wrapper.instance().onMapSingleClick;
+    const onPointerMove = instance.onMapPointerMove;
+    const onMapSingleClick = instance.onMapSingleClick;
 
     wrapper.unmount();
 
@@ -111,8 +121,8 @@ describe('<AgFeatureGrid />', () => {
 
   it('generates the column definition out of the given features and takes attributeBlacklist into account', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features});
-
-    const got = wrapper.instance().getColumnDefs();
+    const instance = wrapper.instance() as AgFeatureGrid;
+    const got = instance.getColumnDefs();
 
     const exp = [{
       field: 'id',
@@ -128,7 +138,7 @@ describe('<AgFeatureGrid />', () => {
       attributeBlacklist: ['id']
     });
 
-    const gotBlacklisted = wrapper.instance().getColumnDefs();
+    const gotBlacklisted = instance.getColumnDefs();
 
     const expBlacklisted = [{
       field: 'name',
@@ -140,8 +150,8 @@ describe('<AgFeatureGrid />', () => {
 
   it('generates the appropriate data to render', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features});
-
-    const got = wrapper.instance().getRowData();
+    const instance = wrapper.instance() as AgFeatureGrid;
+    const got = instance.getRowData();
 
     const expRows = [{
       id: 1,
@@ -155,21 +165,25 @@ describe('<AgFeatureGrid />', () => {
     }];
 
     expRows.forEach((row, idx) => {
-      expect(row.id).toEqual(got[idx].id);
-      expect(row.name).toEqual(got[idx].name);
+      let gotElement = got[idx] as any;
+      expect(row.id).toEqual(gotElement.id);
+      expect(row.name).toEqual(gotElement.name);
     });
   });
 
   it('fits the map to show all given features', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features});
+    const instance = wrapper.instance() as AgFeatureGrid;
 
     const mapViewFitSpy = jest.spyOn(map.getView(), 'fit');
 
-    wrapper.instance().zoomToFeatures(features);
+    instance.zoomToFeatures(features);
 
-    const featGeometries = [];
+    const featGeometries: OlGeometry[] = [];
     features.forEach(feature => {
-      featGeometries.push(feature.getGeometry());
+      if (!_isNil(feature.getGeometry())) {
+        featGeometries.push(feature.getGeometry()!);
+      }
     });
 
     expect(mapViewFitSpy).toHaveBeenCalledWith(new OlGeomGeometryCollection(featGeometries).getExtent());
@@ -177,8 +191,8 @@ describe('<AgFeatureGrid />', () => {
 
   it('highlights all given features', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features});
-
-    wrapper.instance().highlightFeatures(features);
+    const instance = wrapper.instance() as AgFeatureGrid;
+    instance.highlightFeatures(features);
 
     features.forEach(feature => {
       expect(feature.getStyle()).toEqual(wrapper.prop('highlightStyle'));
@@ -187,8 +201,8 @@ describe('<AgFeatureGrid />', () => {
 
   it('selects all given features', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features});
-
-    wrapper.instance().selectFeatures(features);
+    const instance = wrapper.instance() as AgFeatureGrid;
+    instance.selectFeatures(features);
 
     features.forEach(feature => {
       expect(feature.getStyle()).toEqual(wrapper.prop('selectStyle'));
@@ -197,8 +211,8 @@ describe('<AgFeatureGrid />', () => {
 
   it('resets all given features to default feature style', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features});
-
-    wrapper.instance().resetFeatureStyles(features);
+    const instance = wrapper.instance() as AgFeatureGrid;
+    instance.resetFeatureStyles();
 
     features.forEach(feature => {
       expect(feature.getStyle()).toBe(undefined);
@@ -207,22 +221,26 @@ describe('<AgFeatureGrid />', () => {
 
   it('returns the feature for a given row key', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features});
+    const instance = wrapper.instance() as AgFeatureGrid;
+    // @ts-ignore
     const rowKey = features[1].ol_uid;
 
-    expect(wrapper.instance().getFeatureFromRowKey(rowKey)).toEqual(features[1]);
+    expect(instance.getFeatureFromRowKey(rowKey)).toEqual(features[1]);
   });
 
   it('selects the feature on row click', () => {
     const onRowClickSpy = jest.fn();
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features, onRowClick: onRowClickSpy});
+    const instance = wrapper.instance() as AgFeatureGrid;
     const clickedRow = {
       data: {
+        // @ts-ignore
         key: features[0].ol_uid
       }
-    };
-    const zoomToFeaturesSpy = jest.spyOn(wrapper.instance(), 'zoomToFeatures');
+    } as RowClickedEvent;
+    const zoomToFeaturesSpy = jest.spyOn(instance, 'zoomToFeatures');
 
-    wrapper.instance().onRowClick(clickedRow);
+    instance.onRowClick(clickedRow);
 
     expect(onRowClickSpy).toHaveBeenCalled();
     expect(zoomToFeaturesSpy).not.toHaveBeenCalled();
@@ -236,12 +254,14 @@ describe('<AgFeatureGrid />', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map, features, onRowMouseOver: onRowMouseOverSpy});
     const clickedRow = {
       data: {
+        // @ts-ignore
         key: features[0].ol_uid
       }
-    };
-    const highlightFeaturesSpy = jest.spyOn(wrapper.instance(), 'highlightFeatures');
+    } as CellMouseOverEvent;
+    const instance = wrapper.instance() as AgFeatureGrid;
+    const highlightFeaturesSpy = jest.spyOn(instance, 'highlightFeatures');
 
-    wrapper.instance().onRowMouseOver(clickedRow);
+    instance.onRowMouseOver(clickedRow);
 
     expect(onRowMouseOverSpy).toHaveBeenCalled();
     expect(highlightFeaturesSpy).toHaveBeenCalled();
@@ -252,13 +272,13 @@ describe('<AgFeatureGrid />', () => {
 
   it('handles the change of props', () => {
     const wrapper = TestUtil.mountComponent(AgFeatureGrid, {map: map});
+    const instance = wrapper.instance() as AgFeatureGrid;
+    expect(instance._source).toBeInstanceOf(OlSourceVector);
+    expect(instance._layer).toBeInstanceOf(OlLayerVector);
 
-    expect(wrapper.instance()._source).toBeInstanceOf(OlSourceVector);
-    expect(wrapper.instance()._layer).toBeInstanceOf(OlLayerVector);
-
-    expect(wrapper.instance()._source.getFeatures()).toEqual([]);
+    expect(instance._source?.getFeatures()).toEqual([]);
 
-    const zoomToFeaturesSpy = jest.spyOn(wrapper.instance(), 'zoomToFeatures');
+    const zoomToFeaturesSpy = jest.spyOn(instance, 'zoomToFeatures');
 
     wrapper.setProps({
       map: map,
@@ -266,7 +286,7 @@ describe('<AgFeatureGrid />', () => {
       zoomToExtent: true
     });
 
-    expect(wrapper.instance()._source.getFeatures()).toEqual(features);
+    expect(instance._source?.getFeatures()).toEqual(features);
     expect(zoomToFeaturesSpy).toHaveBeenCalled();
 
     zoomToFeaturesSpy.mockRestore();
@@ -329,13 +349,14 @@ describe('<AgFeatureGrid />', () => {
       wrapper.setState({
         selectedRows: selectionCurrent
       }, () => {
+        const instance = wrapper.instance() as AgFeatureGrid;
         const mockedEvt = {
           api: {
             getSelectedRows: mockedGetSelectedRows
-          }
+          },
         };
         act(() => {
-          wrapper.instance().onSelectionChanged(mockedEvt);
+          instance.onSelectionChanged(mockedEvt as any as SelectionChangedEvent);
         });
         expect(onRowSelectionChange).toHaveBeenCalledTimes(1);
         // selectedRows is the first passed parameter
diff --git a/src/Grid/AgFeatureGrid/AgFeatureGrid.tsx b/src/Grid/AgFeatureGrid/AgFeatureGrid.tsx
index e29c2e3d4c..293c7522f8 100644
--- a/src/Grid/AgFeatureGrid/AgFeatureGrid.tsx
+++ b/src/Grid/AgFeatureGrid/AgFeatureGrid.tsx
@@ -245,13 +245,13 @@ export class AgFeatureGrid extends React.Component<AgFeatureGridProps, AgFeature
    * The source holding the features of the grid.
    * @private
    */
-  _source: OlSourceVector<OlGeometry> | null = null;
+  _source: OlSourceVector | null = null;
 
   /**
    * The layer representing the features of the grid.
    * @private
    */
-  _layer: OlLayerVector<OlSourceVector<OlGeometry>> | null = null;
+  _layer: OlLayerVector<OlSourceVector> | null = null;
 
   /**
    * The constructor.
@@ -605,7 +605,7 @@ export class AgFeatureGrid extends React.Component<AgFeatureGridProps, AgFeature
       const properties = feature.getProperties();
       const filtered = Object.keys(properties)
         .filter(key => !(properties[key] instanceof OlGeometry))
-        .reduce((obj, key) => {
+        .reduce((obj: {[k: string]: any}, key) => {
           obj[key] = properties[key];
           return obj;
         }, {});
diff --git a/src/Grid/FeatureGrid/FeatureGrid.spec.tsx b/src/Grid/FeatureGrid/FeatureGrid.spec.tsx
index 36670bb77d..92ede432cf 100644
--- a/src/Grid/FeatureGrid/FeatureGrid.spec.tsx
+++ b/src/Grid/FeatureGrid/FeatureGrid.spec.tsx
@@ -1,7 +1,9 @@
-import { MapBrowserEvent } from 'ol';
+import {MapBrowserEvent} from 'ol';
+import OlFeature from 'ol/Feature';
 import OlGeometry from 'ol/geom/Geometry';
 import OlGeomGeometryCollection from 'ol/geom/GeometryCollection';
 import OlLayerVector from 'ol/layer/Vector';
+import OlMap from 'ol/Map';
 import OlSourceVector from 'ol/source/Vector';
 import {
   act
@@ -11,8 +13,8 @@ import TestUtil from '../../Util/TestUtil';
 import FeatureGrid from './FeatureGrid';
 
 describe('<FeatureGrid />', () => {
-  let map;
-  let features;
+  let map: OlMap;
+  let features: OlFeature[];
 
   beforeEach(() => {
     map = TestUtil.createMap();
@@ -179,7 +181,7 @@ describe('<FeatureGrid />', () => {
     const featGeometries: OlGeometry[] = [];
     features.forEach(feature => {
       if (feature.getGeometry()) {
-        featGeometries.push(feature.getGeometry());
+        featGeometries.push(feature.getGeometry()!);
       }
     });
 
@@ -198,6 +200,7 @@ describe('<FeatureGrid />', () => {
 
   it('unhighlight all given features, but takes selection into account', () => {
     const wrapper = TestUtil.mountComponent(FeatureGrid, {map, features});
+    // @ts-ignore
     const selectedFeatureUid = features[0].ol_uid;
 
     act(() => {
@@ -208,6 +211,7 @@ describe('<FeatureGrid />', () => {
     });
 
     features.forEach(feature => {
+      // @ts-ignore
       if (feature.ol_uid === selectedFeatureUid) {
         expect(feature.getStyle()).toEqual(wrapper.prop('selectStyle'));
       } else {
@@ -238,6 +242,7 @@ describe('<FeatureGrid />', () => {
 
   it('sets the appropriate select style to a feature if selection in grid changes', () => {
     const wrapper = TestUtil.mountComponent(FeatureGrid, {map, features});
+    // @ts-ignore
     const selectedRowKeys = [features[0].ol_uid, features[1].ol_uid];
 
     act(() => {
@@ -245,6 +250,7 @@ describe('<FeatureGrid />', () => {
     });
 
     features.forEach(feature => {
+      // @ts-ignore
       if (selectedRowKeys.includes(feature.ol_uid)) {
         expect(feature.getStyle()).toEqual(wrapper.prop('selectStyle'));
       } else {
@@ -257,6 +263,7 @@ describe('<FeatureGrid />', () => {
 
   it('returns the feature for a given row key', () => {
     const wrapper = TestUtil.mountComponent(FeatureGrid, {map, features});
+    // @ts-ignore
     const rowKey = features[1].ol_uid;
 
     expect((wrapper.instance() as FeatureGrid).getFeatureFromRowKey(rowKey)).toEqual(features[1]);
@@ -266,6 +273,7 @@ describe('<FeatureGrid />', () => {
     const onRowClickSpy = jest.fn();
     const wrapper = TestUtil.mountComponent(FeatureGrid, {map, features, onRowClick: onRowClickSpy});
     const clickedRow = {
+      // @ts-ignore
       key: features[0].ol_uid
     };
     const zoomToFeaturesSpy = jest.spyOn((wrapper.instance() as FeatureGrid), 'zoomToFeatures');
@@ -283,6 +291,7 @@ describe('<FeatureGrid />', () => {
     const onRowMouseOverSpy = jest.fn();
     const wrapper = TestUtil.mountComponent(FeatureGrid, {map, features, onRowMouseOver: onRowMouseOverSpy});
     const clickedRow = {
+      // @ts-ignore
       key: features[0].ol_uid
     };
     const highlightFeaturesSpy = jest.spyOn((wrapper.instance() as FeatureGrid), 'highlightFeatures');
@@ -300,6 +309,7 @@ describe('<FeatureGrid />', () => {
     const onRowMouseOutSpy = jest.fn();
     const wrapper = TestUtil.mountComponent(FeatureGrid, {map, features, onRowMouseOut: onRowMouseOutSpy});
     const clickedRow = {
+      // @ts-ignore
       key: features[0].ol_uid
     };
     const unhighlightFeaturesSpy = jest.spyOn((wrapper.instance() as FeatureGrid), 'unhighlightFeatures');
diff --git a/src/Grid/FeatureGrid/FeatureGrid.tsx b/src/Grid/FeatureGrid/FeatureGrid.tsx
index ee025a3161..62528fe067 100644
--- a/src/Grid/FeatureGrid/FeatureGrid.tsx
+++ b/src/Grid/FeatureGrid/FeatureGrid.tsx
@@ -212,13 +212,13 @@ export class FeatureGrid extends React.Component<FeatureGridProps, FeatureGridSt
    * The source holding the features of the grid.
    * @private
    */
-  _source: OlSourceVector<OlGeometry> | null = null;
+  _source: OlSourceVector | null = null;
 
   /**
    * The layer representing the features of the grid.
    * @private
    */
-  _layer: OlLayerVector<OlSourceVector<OlGeometry>> | null = null;
+  _layer: OlLayerVector<OlSourceVector> | null = null;
 
   /**
    * The constructor.
@@ -524,6 +524,7 @@ export class FeatureGrid extends React.Component<FeatureGridProps, FeatureGridSt
         title: key,
         dataIndex: key,
         key: key,
+        // @ts-ignore
         ...columnDefs[key]
       });
     });
@@ -532,7 +533,7 @@ export class FeatureGrid extends React.Component<FeatureGridProps, FeatureGridSt
   };
 
   /**
-   * Returns the table row data from all of the given features.
+   * Returns the table row data from all the given features.
    *
    * @return The table data.
    */
@@ -548,7 +549,7 @@ export class FeatureGrid extends React.Component<FeatureGridProps, FeatureGridSt
       const properties = feature.getProperties();
       const filtered: typeof properties = Object.keys(properties)
         .filter(key => !(properties[key] instanceof OlGeometry))
-        .reduce((obj, key) => {
+        .reduce((obj: {[k: string]: any}, key) => {
           obj[key] = properties[key];
           return obj;
         }, {});
diff --git a/src/Grid/PropertyGrid/PropertyGrid.spec.tsx b/src/Grid/PropertyGrid/PropertyGrid.spec.tsx
index ef72cd73ae..c2d676e963 100644
--- a/src/Grid/PropertyGrid/PropertyGrid.spec.tsx
+++ b/src/Grid/PropertyGrid/PropertyGrid.spec.tsx
@@ -1,3 +1,5 @@
+import _get from 'lodash/get';
+import _isNil from 'lodash/isNil';
 import OlFeature from 'ol/Feature';
 import OlGeomPoint from 'ol/geom/Point';
 
@@ -58,8 +60,9 @@ describe('<PropertyGrid />', () => {
     expect(dataSource).toHaveLength(Object.keys(attributeObject).length);
     dataSource.forEach((dataSourceElement) => {
       const attributeName = dataSourceElement.attributeName;
+      // @ts-ignore
       const key = `ATTR_${attributeName}_fid_${testFeature.ol_uid}`;
-      expect(attributeObject[attributeName]).toBe(dataSourceElement.attributeValue);
+      expect(_get(attributeObject,attributeName)).toBe(dataSourceElement.attributeValue);
       expect(key).toBe(dataSourceElement.key);
     });
 
@@ -125,9 +128,9 @@ describe('<PropertyGrid />', () => {
     dataSource.forEach((dataSourceElement) => {
       const key = dataSourceElement.key;
       const orignalAttributeName = key.split('_')[1];
-      if (attributeNames[orignalAttributeName]) {
+      if (!_isNil(_get(attributeNames, orignalAttributeName))) {
         const mappedAttributeNameInDataSource = dataSourceElement.attributeName;
-        expect(mappedAttributeNameInDataSource).toBe(attributeNames[orignalAttributeName]);
+        expect(mappedAttributeNameInDataSource).toEqual(_get(attributeNames, orignalAttributeName));
       }
     });
   });
diff --git a/src/LayerSwitcher/LayerSwitcher.spec.tsx b/src/LayerSwitcher/LayerSwitcher.spec.tsx
index ed05f0e7ff..68fcabb89d 100644
--- a/src/LayerSwitcher/LayerSwitcher.spec.tsx
+++ b/src/LayerSwitcher/LayerSwitcher.spec.tsx
@@ -1,6 +1,8 @@
 import { render, screen,within } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
+import OlLayer from 'ol/layer/Layer';
 import OlLayerTile from 'ol/layer/Tile';
+import OlMap from 'ol/Map';
 import OlSourceOsm from 'ol/source/OSM';
 import React from 'react';
 
@@ -8,8 +10,8 @@ import TestUtil from '../Util/TestUtil';
 import LayerSwitcher from './LayerSwitcher';
 
 describe('<LayerSwitcher />', () => {
-  let map;
-  let layers;
+  let map: OlMap;
+  let layers: OlLayer[];
 
   beforeEach(() => {
     layers = [
@@ -26,9 +28,8 @@ describe('<LayerSwitcher />', () => {
   });
 
   afterEach(() => {
-    map.dispose();
-    layers = null;
-    map = null;
+    map?.dispose();
+    layers = [];
   });
 
   it('is defined', () => {
@@ -78,13 +79,13 @@ describe('<LayerSwitcher />', () => {
     const { container } = render(<LayerSwitcher layers={layers} map={map} />);
     const switcher = within(container).getByRole('button');
 
-    const layer0visibile = layers[0].getVisible();
-    const layer1visibile = layers[1].getVisible();
+    const layer0visible = layers[0].getVisible();
+    const layer1visible = layers[1].getVisible();
 
     await userEvent.click(switcher);
 
-    expect(layers[0].getVisible()).toBe(!layer0visibile);
-    expect(layers[1].getVisible()).toBe(!layer1visibile);
+    expect(layers[0].getVisible()).toBe(!layer0visible);
+    expect(layers[1].getVisible()).toBe(!layer1visible);
   });
 
   it('assumes the first provided layer as visible if the initial visibility of all layers is false', () => {
diff --git a/src/LayerTree/LayerTreeNode/LayerTreeNode.spec.tsx b/src/LayerTree/LayerTreeNode/LayerTreeNode.spec.tsx
index ce8456ae59..f3c464ef56 100644
--- a/src/LayerTree/LayerTreeNode/LayerTreeNode.spec.tsx
+++ b/src/LayerTree/LayerTreeNode/LayerTreeNode.spec.tsx
@@ -8,7 +8,7 @@ describe('<LayerTreeNode />', () => {
 
   const defaultProps = {
     inResolutionRange: true,
-    filterTreeNode: ftn => ftn
+    filterTreeNode: jest.fn()
   };
 
   it('is defined', () => {
diff --git a/src/Panel/TimeLayerSliderPanel/TimeLayerSliderPanel.spec.tsx b/src/Panel/TimeLayerSliderPanel/TimeLayerSliderPanel.spec.tsx
index b36fbc0cb6..b0603fd5e7 100644
--- a/src/Panel/TimeLayerSliderPanel/TimeLayerSliderPanel.spec.tsx
+++ b/src/Panel/TimeLayerSliderPanel/TimeLayerSliderPanel.spec.tsx
@@ -2,6 +2,7 @@ import { render, screen } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 import moment from 'moment';
 import OlLayerTile from 'ol/layer/Tile';
+import OlMap from 'ol/Map';
 import OlSourceTileWMS from 'ol/source/TileWMS';
 import * as React from 'react';
 
@@ -10,20 +11,22 @@ import TimeLayerSliderPanel from '../TimeLayerSliderPanel/TimeLayerSliderPanel';
 
 describe('<TimeLayerSliderPanel />', () => {
 
-  let map;
+  let map: OlMap;
 
   const testLayerName = 'OSM-WMS';
   const testLayerTitle = 'OSM-WMS - by terrestris';
   const testLayer = new OlLayerTile({
     visible: false,
-    title: testLayerTitle,
     source: new OlSourceTileWMS({
       url: 'https://ows.terrestris.de/osm/service?',
       params: {
         LAYERS: testLayerName,
         TILED: true
       }
-    })
+    }),
+    properties: {
+      title: testLayerTitle
+    }
   });
 
   beforeEach(() => {
diff --git a/src/Panel/TimeLayerSliderPanel/TimeLayerSliderPanel.tsx b/src/Panel/TimeLayerSliderPanel/TimeLayerSliderPanel.tsx
index 37eb293446..08e28f9ce2 100644
--- a/src/Panel/TimeLayerSliderPanel/TimeLayerSliderPanel.tsx
+++ b/src/Panel/TimeLayerSliderPanel/TimeLayerSliderPanel.tsx
@@ -69,7 +69,7 @@ export class TimeLayerSliderPanel extends React.Component<TimeLayerSliderPanelPr
    * The default props of LayerSetBaseMapChooser
    *
    * @static
-   * @memberof LayerSetBaseMapChooser
+   * @memberof TimeLayerSliderPanel
    */
   public static defaultProps = {
     className: '',
@@ -399,7 +399,7 @@ export class TimeLayerSliderPanel extends React.Component<TimeLayerSliderPanelPr
     const endDateString = endDate.toISOString();
     const valueString = value.toISOString();
     const mid = startDate!.clone().add(endDate!.diff(startDate) / 2);
-    const marks = {};
+    const marks: {[k: string]: any} = {};
     const futureClass = moment().isBefore(value) ? ' timeslider-in-future' : '';
     const extraCls = className ? className : '';
     const disabledCls = timeAwareLayers.length < 1 ? 'no-layers-available' : '';
diff --git a/src/Slider/LayerTransparencySlider/LayerTransparencySlider.spec.tsx b/src/Slider/LayerTransparencySlider/LayerTransparencySlider.spec.tsx
index 10f2235482..48bdcc66ef 100644
--- a/src/Slider/LayerTransparencySlider/LayerTransparencySlider.spec.tsx
+++ b/src/Slider/LayerTransparencySlider/LayerTransparencySlider.spec.tsx
@@ -1,11 +1,13 @@
+import OlLayer from 'ol/layer/Layer';
+
 import TestUtil from '../../Util/TestUtil';
 import LayerTransparencySlider from './LayerTransparencySlider';
 
 describe('<LayerTransparencySlider />', () => {
-  let layer;
+  let layer: OlLayer;
 
   beforeEach(() => {
-    layer = TestUtil.createVectorLayer();
+    layer = TestUtil.createVectorLayer({});
   });
 
   it('is defined', () => {
@@ -27,7 +29,8 @@ describe('<LayerTransparencySlider />', () => {
     };
 
     const wrapper = TestUtil.mountComponent(LayerTransparencySlider, props);
-    const transparency = wrapper.instance().getLayerTransparency();
+    const instance = wrapper.instance() as LayerTransparencySlider;
+    const transparency = instance.getLayerTransparency();
     expect(transparency).toBe(91);
   });
 
@@ -36,8 +39,9 @@ describe('<LayerTransparencySlider />', () => {
       layer: layer
     };
     const wrapper = TestUtil.mountComponent(LayerTransparencySlider, props);
+    const instance = wrapper.instance() as LayerTransparencySlider;
 
-    wrapper.instance().setLayerTransparency(91);
+    instance.setLayerTransparency(91);
     expect(layer.getOpacity()).toBe(0.09);
   });
 
diff --git a/src/Slider/MultiLayerSlider/MultiLayerSlider.spec.tsx b/src/Slider/MultiLayerSlider/MultiLayerSlider.spec.tsx
index 1839d347ce..e13d40d817 100644
--- a/src/Slider/MultiLayerSlider/MultiLayerSlider.spec.tsx
+++ b/src/Slider/MultiLayerSlider/MultiLayerSlider.spec.tsx
@@ -1,8 +1,10 @@
+import OlLayer from 'ol/layer/Layer';
+
 import TestUtil from '../../Util/TestUtil';
 import MultiLayerSlider from './MultiLayerSlider';
 
 describe('<MultiLayerSlider />', () => {
-  let layers;
+  let layers: OlLayer[];
 
   beforeEach(() => {
     layers = [
diff --git a/src/Slider/MultiLayerSlider/MultiLayerSlider.tsx b/src/Slider/MultiLayerSlider/MultiLayerSlider.tsx
index 16dcde6aa5..7426a8fe10 100644
--- a/src/Slider/MultiLayerSlider/MultiLayerSlider.tsx
+++ b/src/Slider/MultiLayerSlider/MultiLayerSlider.tsx
@@ -151,7 +151,7 @@ class MultiLayerSlider extends React.Component<MultiLayerSliderProps> {
    * @return The marks object
    */
   getMarks() {
-    const marks = {};
+    const marks: {[index: number]: any} = {};
     const {
       layers,
       nameProperty
diff --git a/src/Slider/TimeSlider/TimeSlider.spec.tsx b/src/Slider/TimeSlider/TimeSlider.spec.tsx
index e04fdda4ab..1317447dac 100644
--- a/src/Slider/TimeSlider/TimeSlider.spec.tsx
+++ b/src/Slider/TimeSlider/TimeSlider.spec.tsx
@@ -14,7 +14,7 @@ describe('<TimeSlider />', () => {
   });
 
   it('converts time millis properly', () => {
-    const slider = TestUtil.mountComponent(TimeSlider, {}).instance();
+    const slider = TestUtil.mountComponent(TimeSlider, {}).instance() as TimeSlider;
     const time = moment(1500000000000);
     const unix = slider.convert(time);
     expect(unix).toBe(1500000000);
@@ -35,7 +35,7 @@ describe('<TimeSlider />', () => {
       max: max.unix(),
       defaultValue: defaultValue.unix()
     };
-    const slider = TestUtil.mountComponent(TimeSlider, props).instance();
+    const slider = TestUtil.mountComponent(TimeSlider, props).instance() as TimeSlider;
     const got = slider.convertTimestamps();
     expect(got).toEqual(expected);
   });
@@ -47,7 +47,7 @@ describe('<TimeSlider />', () => {
     const expected1 = val1.unix();
     const expected2 = [expected1, val2.unix()];
 
-    const slider = TestUtil.mountComponent(TimeSlider, {}).instance();
+    const slider = TestUtil.mountComponent(TimeSlider, {}).instance() as TimeSlider;
     const got1 = slider.convert(val1);
     const got2 = slider.convert([val1, val2]);
 
@@ -60,20 +60,20 @@ describe('<TimeSlider />', () => {
       const format = 'YYYY-MM-DD hh:mm:ss';
       const val1 = moment('2000-01-01 12:00:00', format);
       const val2 = moment('2001-01-01 12:00:00', format);
-      const marks = {};
-      marks[val1] = val1;
-      marks[val2] = val2;
+      const marks: any = {};
+      marks['2000-01-01 12:00:00'] = val1;
+      marks['2001-01-01 12:00:00'] = val2;
 
       const expected1 = val1.unix();
       const expected2 = val2.unix();
 
-      const slider = TestUtil.mountComponent(TimeSlider, {}).instance();
+      const slider = TestUtil.mountComponent(TimeSlider, {}).instance() as TimeSlider;
       const gotMarks = slider.convertMarks(marks);
-      const gotKeys = Object.keys(gotMarks);
+      const gotKeys = Object.keys(gotMarks!);
 
       expect(gotKeys).toEqual(expect.arrayContaining([expected1.toString(), expected2.toString()]));
-      expect(gotMarks[expected1]).toEqual(val1);
-      expect(gotMarks[expected2]).toEqual(val2);
+      expect(gotMarks![expected1]).toEqual(val1);
+      expect(gotMarks![expected2]).toEqual(val2);
     });
   });
 
@@ -82,7 +82,7 @@ describe('<TimeSlider />', () => {
     const formatted = '2000-01-01 12:00:00';
     const val = moment(formatted, format).unix();
 
-    const slider = TestUtil.mountComponent(TimeSlider, {formatString: format}).instance();
+    const slider = TestUtil.mountComponent(TimeSlider, {formatString: format}).instance() as TimeSlider;
 
     const got = slider.formatTimestamp(val);
     expect(got).toEqual(formatted);
@@ -96,7 +96,7 @@ describe('<TimeSlider />', () => {
     const expected1 = moment(val1.unix() * 1000).toISOString();
     const expected2 = [expected1, moment(val2.unix() * 1000).toISOString()];
 
-    const slider = TestUtil.mountComponent(TimeSlider, {onChange}).instance();
+    const slider = TestUtil.mountComponent(TimeSlider, {onChange}).instance() as TimeSlider;
 
     slider.valueUpdated(val1.unix());
     expect(onChange.mock.calls.length).toBe(1);
diff --git a/src/Slider/TimeSlider/TimeSlider.tsx b/src/Slider/TimeSlider/TimeSlider.tsx
index 62bc0da7d8..c6cb688f2e 100644
--- a/src/Slider/TimeSlider/TimeSlider.tsx
+++ b/src/Slider/TimeSlider/TimeSlider.tsx
@@ -2,7 +2,7 @@ import { Slider } from 'antd';
 import { SliderBaseProps,SliderMarks } from 'antd/lib/slider';
 import _isArray from 'lodash/isArray';
 import _isObject from 'lodash/isObject';
-import moment from 'moment';
+import moment, {Moment} from 'moment';
 import * as React from 'react';
 
 import { CSS_PREFIX } from '../../constants';
@@ -103,7 +103,7 @@ class TimeSlider extends React.Component<TimeSliderProps> {
    * @param val the input value(s)
    * @return The converted value(s)
    */
-  convert(val: string[] | string): number | [number, number] {
+  convert(val: string[] | string | Moment | Moment[]): number | [number, number] {
     return _isArray(val) ?
       (val as Array<string>).map(iso => moment(iso).unix()) as [number, number]:
       moment(val).unix() as number;
diff --git a/src/Util/TestUtil.tsx b/src/Util/TestUtil.tsx
index 7453a7813f..2b9b4b027a 100644
--- a/src/Util/TestUtil.tsx
+++ b/src/Util/TestUtil.tsx
@@ -8,7 +8,7 @@ import OlSourceVector from 'ol/source/Vector';
 import OlView from 'ol/View';
 import * as React from 'react';
 
-type Wrapper =  ShallowWrapper | ReactWrapper;
+export type Wrapper =  ShallowWrapper | ReactWrapper;
 
 /**
  * A set of some useful static helper methods.
@@ -140,7 +140,7 @@ export class TestUtil {
       clientY: position.top + y + TestUtil.mapDivHeight / 2,
       shiftKey
     });
-    const olEvt = OlMapBrowserEvent(type, map, event, dragging);
+    const olEvt = new OlMapBrowserEvent(type, map, event, dragging);
     map.handleMapBrowserEvent(olEvt);
   };
 
@@ -162,7 +162,7 @@ export class TestUtil {
   /**
    * Returns a point feature with a random position.
    */
-  static generatePointFeature = (props = {
+  static generatePointFeature = (props: {[k: string]: any} = {
     ATTR_1: Math.random() * 100,
     ATTR_2: 'Borsigplatz 9',
     ATTR_3: 'Dortmund'
diff --git a/src/Util/antdTestQueries.ts b/src/Util/antdTestQueries.ts
index 75c3eecbab..ccda92b394 100644
--- a/src/Util/antdTestQueries.ts
+++ b/src/Util/antdTestQueries.ts
@@ -1,3 +1,4 @@
+// @ts-nocheck
 import {buildQueries, queryAllByTitle} from '@testing-library/react';
 
 const allAntdDropdownOptionQuery = (container) => {
diff --git a/src/custom.d.ts b/src/custom.d.ts
index b9d7c54b17..62b95b45c7 100644
--- a/src/custom.d.ts
+++ b/src/custom.d.ts
@@ -1,7 +1,2 @@
 declare module '*.png';
-declare module 'ol';
-declare module 'ol/format';
-declare module 'ol/layer';
-declare module 'ol/source';
-declare module 'ol/geom';
 declare module '@camptocamp/inkmap';
diff --git a/tsconfig.json b/tsconfig.json
index bdb8793e39..81b3209415 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -18,8 +18,8 @@
     "rootDir": "src",
     "skipLibCheck": true,
     "sourceMap": true,
-    "suppressImplicitAnyIndexErrors": true,
-    "target": "es5"
+    "target": "es5",
+    "types": ["node", "jest", "@testing-library/jest-dom"]
   },
   "exclude": [
     "node_modules",
@@ -34,7 +34,6 @@
     "jest",
     "coverage",
     "src/Util/**",
-    "**.config.js",
-    "**/*.spec.tsx"
+    "src/**/*.spec.ts"
   ]
 }