diff --git a/.eslintrc.js b/.eslintrc.js
index d61dd21569..34ca5086c3 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -62,6 +62,25 @@ module.exports = {
         '@typescript-eslint/no-redeclare': ['error'],
       },
     },
+    {
+      files: ['*.ts', '*.tsx'],
+      // this is the same files as ignored in tsconfig.json
+      excludedFiles: [
+        "examples/**/*",
+        "es",
+        // these two files are temporarily excluded because
+        // they import files from node_modules/search-insights directly
+        // and it causes the type-checking to fail.
+        "src/middlewares/__tests__/createInsightsMiddleware.ts",
+        "test/mock/createInsightsClient.ts"
+      ],
+      parserOptions: {
+        project: './tsconfig.json',
+      },
+      rules: {
+        '@typescript-eslint/no-unnecessary-type-assertion': 'error',
+      },
+    },
     {
       files: ['*.js'],
       rules: {
diff --git a/src/components/Panel/Panel.tsx b/src/components/Panel/Panel.tsx
index dfc0df3e8b..44173267de 100644
--- a/src/components/Panel/Panel.tsx
+++ b/src/components/Panel/Panel.tsx
@@ -40,14 +40,15 @@ function Panel<TWidget extends UnknownWidgetFactory>(
   const bodyRef = useRef<HTMLElement | null>(null);
 
   useEffect(() => {
-    if (!bodyRef.current) {
+    const node = bodyRef.current;
+    if (!node) {
       return undefined;
     }
 
-    bodyRef.current.appendChild(props.bodyElement);
+    node.appendChild(props.bodyElement);
 
     return () => {
-      bodyRef!.current!.removeChild(props.bodyElement);
+      node.removeChild(props.bodyElement);
     };
   }, [bodyRef, props.bodyElement]);
 
diff --git a/src/components/Slider/Rheostat.tsx b/src/components/Slider/Rheostat.tsx
index 892737226e..73ae981f7f 100644
--- a/src/components/Slider/Rheostat.tsx
+++ b/src/components/Slider/Rheostat.tsx
@@ -303,7 +303,7 @@ class Rheostat extends Component<Props, State> {
     if (!this.props.snapPoints!.length) return value;
 
     return this.props.snapPoints!.reduce((snapTo, snap) =>
-      Math.abs(snapTo! - value) < Math.abs(snap - value) ? snapTo : snap
+      Math.abs(snapTo - value) < Math.abs(snap - value) ? snapTo : snap
     );
   }
 
diff --git a/src/connectors/answers/connectAnswers.ts b/src/connectors/answers/connectAnswers.ts
index b9a864d901..56b1e104e1 100644
--- a/src/connectors/answers/connectAnswers.ts
+++ b/src/connectors/answers/connectAnswers.ts
@@ -146,7 +146,7 @@ const connectAnswers: AnswersConnector = function connectAnswers(
 
       init(initOptions) {
         const { state, instantSearchInstance } = initOptions;
-        const answersIndex = instantSearchInstance.client!.initIndex!(
+        const answersIndex = instantSearchInstance.client.initIndex!(
           state.index
         );
         if (!hasFindAnswersMethod(answersIndex)) {
diff --git a/src/connectors/autocomplete/__tests__/connectAutocomplete-test.ts b/src/connectors/autocomplete/__tests__/connectAutocomplete-test.ts
index 705619e1c5..aee0937bde 100644
--- a/src/connectors/autocomplete/__tests__/connectAutocomplete-test.ts
+++ b/src/connectors/autocomplete/__tests__/connectAutocomplete-test.ts
@@ -556,7 +556,7 @@ search.addWidgets([
     test('should give back the object unmodified if the default value is selected', () => {
       const [widget, helper] = getInitializedWidget();
       const uiStateBefore = {};
-      const uiStateAfter = widget.getWidgetUiState!(uiStateBefore, {
+      const uiStateAfter = widget.getWidgetUiState(uiStateBefore, {
         searchParameters: helper.state,
         helper,
       });
@@ -567,7 +567,7 @@ search.addWidgets([
       const [widget, helper, refine] = getInitializedWidget();
       refine('some query');
       const uiStateBefore = {};
-      const uiStateAfter = widget.getWidgetUiState!(uiStateBefore, {
+      const uiStateAfter = widget.getWidgetUiState(uiStateBefore, {
         searchParameters: helper.state,
         helper,
       });
@@ -579,14 +579,14 @@ search.addWidgets([
     test('should give back the same instance if the value is already in the uiState', () => {
       const [widget, helper, refine] = getInitializedWidget();
       refine('query');
-      const uiStateBefore = widget.getWidgetUiState!(
+      const uiStateBefore = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
           helper,
         }
       );
-      const uiStateAfter = widget.getWidgetUiState!(uiStateBefore, {
+      const uiStateAfter = widget.getWidgetUiState(uiStateBefore, {
         searchParameters: helper.state,
         helper,
       });
@@ -604,7 +604,7 @@ search.addWidgets([
         })
       );
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           query: 'Apple',
         },
@@ -628,7 +628,7 @@ search.addWidgets([
         })
       );
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -652,7 +652,7 @@ search.addWidgets([
         })
       );
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -676,7 +676,7 @@ search.addWidgets([
         })
       );
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
diff --git a/src/connectors/autocomplete/connectAutocomplete.ts b/src/connectors/autocomplete/connectAutocomplete.ts
index f4964aeadf..ead450848e 100644
--- a/src/connectors/autocomplete/connectAutocomplete.ts
+++ b/src/connectors/autocomplete/connectAutocomplete.ts
@@ -176,7 +176,7 @@ search.addWidgets([
           const sendEvent = createSendEventForHits({
             instantSearchInstance,
             index: scopedResult.results.index,
-            widgetType: this.$$type!,
+            widgetType: this.$$type,
           });
 
           return {
@@ -191,7 +191,7 @@ search.addWidgets([
         return {
           currentRefinement: helper.state.query || '',
           indices,
-          refine: connectorState.refine!,
+          refine: connectorState.refine,
           widgetParams,
         };
       },
diff --git a/src/connectors/configure/__tests__/connectConfigure-test.ts b/src/connectors/configure/__tests__/connectConfigure-test.ts
index 65335be99e..9f071df1f3 100644
--- a/src/connectors/configure/__tests__/connectConfigure-test.ts
+++ b/src/connectors/configure/__tests__/connectConfigure-test.ts
@@ -88,7 +88,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
     });
 
     expect(
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     ).toEqual(
@@ -107,7 +107,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
     });
 
     expect(
-      widget.getWidgetSearchParameters!(
+      widget.getWidgetSearchParameters(
         new SearchParameters({
           analytics: false,
         }),
@@ -120,7 +120,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
     );
 
     expect(
-      widget.getWidgetSearchParameters!(
+      widget.getWidgetSearchParameters(
         new SearchParameters({
           analytics: false,
           clickAnalytics: true,
@@ -145,7 +145,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
     });
 
     helper.setState(
-      widget.getWidgetSearchParameters!(
+      widget.getWidgetSearchParameters(
         new SearchParameters({
           // This facet is added outside of the widget params
           // so it shouldn't be overridden when calling `refine`.
@@ -157,7 +157,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
     widget.init!(createInitOptions({ helper }));
 
     expect(
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: { configure: { analytics: true } },
       })
     ).toEqual(
@@ -177,7 +177,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
     refine({ hitsPerPage: 3, facets: ['rating'] });
 
     expect(
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: { configure: { hitsPerPage: 3, facets: ['rating'] } },
       })
     ).toEqual(
@@ -203,7 +203,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
     });
 
     helper.setState(
-      widget.getWidgetSearchParameters!(
+      widget.getWidgetSearchParameters(
         new SearchParameters({
           clickAnalytics: true,
         }),
@@ -213,7 +213,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
     widget.init!(createInitOptions({ helper }));
 
     expect(
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: { configure: { analytics: true } },
       })
     ).toEqual(
@@ -374,7 +374,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
       });
 
       expect(
-        widget.getWidgetUiState!({}, { helper, searchParameters: helper.state })
+        widget.getWidgetUiState({}, { helper, searchParameters: helper.state })
       ).toEqual({
         configure: { analytics: true },
       });
@@ -395,7 +395,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
       refine({ analytics: false });
 
       expect(
-        widget.getWidgetUiState!({}, { helper, searchParameters: helper.state })
+        widget.getWidgetUiState({}, { helper, searchParameters: helper.state })
       ).toEqual({
         configure: { analytics: false },
       });
@@ -416,7 +416,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
       refine({ query: 'unsafe toys' });
 
       expect(
-        widget.getWidgetUiState!({}, { helper, searchParameters: helper.state })
+        widget.getWidgetUiState({}, { helper, searchParameters: helper.state })
       ).toEqual({
         configure: { query: 'unsafe toys' },
       });
@@ -431,7 +431,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
       });
 
       expect(
-        widget.getWidgetUiState!(
+        widget.getWidgetUiState(
           { configure: { queryType: 'prefixAll' } },
           { helper, searchParameters: helper.state }
         )
@@ -449,7 +449,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
       });
 
       expect(
-        widget.getWidgetUiState!(
+        widget.getWidgetUiState(
           { configure: { analytics: false } },
           { helper, searchParameters: helper.state }
         )
@@ -468,7 +468,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
         },
       });
 
-      const sp = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const sp = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
 
@@ -479,7 +479,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
       const makeWidget = connectConfigure(noop);
       const widget = makeWidget({ searchParameters: {} });
 
-      const sp = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const sp = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {
           configure: {
             analytics: false,
@@ -498,7 +498,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
         },
       });
 
-      const sp = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const sp = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {
           configure: {
             analytics: false,
@@ -517,7 +517,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
         },
       });
 
-      const sp = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const sp = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {
           configure: {
             analytics: false,
@@ -544,7 +544,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
         },
       });
 
-      const sp = widget.getWidgetSearchParameters!(
+      const sp = widget.getWidgetSearchParameters(
         new SearchParameters({
           disjunctiveFacets: ['categories'],
           disjunctiveFacetsRefinements: {
@@ -581,7 +581,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/configure/j
 
       refine({ analyticsTags: ['worst-site-now'] });
 
-      const sp = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const sp = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
 
diff --git a/src/connectors/dynamic-widgets/connectDynamicWidgets.ts b/src/connectors/dynamic-widgets/connectDynamicWidgets.ts
index f98a68d057..5f14d183e9 100644
--- a/src/connectors/dynamic-widgets/connectDynamicWidgets.ts
+++ b/src/connectors/dynamic-widgets/connectDynamicWidgets.ts
@@ -131,7 +131,7 @@ const connectDynamicWidgets: DynamicWidgetsConnector =
               toRemove.push(widget);
             }
           });
-          parent!.removeWidgets(toRemove);
+          parent.removeWidgets(toRemove);
 
           unmountFn();
         },
diff --git a/src/connectors/geo-search/__tests__/connectGeoSearch-test.ts b/src/connectors/geo-search/__tests__/connectGeoSearch-test.ts
index e7dfa05cd4..d9af6adfc9 100644
--- a/src/connectors/geo-search/__tests__/connectGeoSearch-test.ts
+++ b/src/connectors/geo-search/__tests__/connectGeoSearch-test.ts
@@ -74,7 +74,7 @@ describe('connectGeoSearch', () => {
       })
     );
 
-    const results = new SearchResults(helper!.state, [
+    const results = new SearchResults(helper.state, [
       createSingleSearchResponse({
         hits,
       }),
diff --git a/src/connectors/hierarchical-menu/__tests__/connectHierarchicalMenu-test.ts b/src/connectors/hierarchical-menu/__tests__/connectHierarchicalMenu-test.ts
index 70e490ec1f..11bc0df782 100644
--- a/src/connectors/hierarchical-menu/__tests__/connectHierarchicalMenu-test.ts
+++ b/src/connectors/hierarchical-menu/__tests__/connectHierarchicalMenu-test.ts
@@ -88,7 +88,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       attributes: ['category', 'sub_category'],
     });
 
-    const config = widget.getWidgetSearchParameters!(new SearchParameters(), {
+    const config = widget.getWidgetSearchParameters(new SearchParameters(), {
       uiState: {},
     });
     expect(config).toEqual(
@@ -162,7 +162,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
     const helper = algoliasearchHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -211,7 +211,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
     const helper = algoliasearchHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -320,7 +320,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
     const helper = algoliasearchHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -388,7 +388,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -407,7 +407,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         indexName,
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -427,7 +427,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         indexName,
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -468,7 +468,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         'indexName',
-        hierarchicalMenu.getWidgetSearchParameters!(new SearchParameters(), {
+        hierarchicalMenu.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -525,7 +525,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         'indexName',
-        hierarchicalMenu.getWidgetSearchParameters!(new SearchParameters(), {
+        hierarchicalMenu.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -560,7 +560,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
               }),
             ]),
           })
-        ).hierarchicalMenu!.category
+        ).hierarchicalMenu.category
       ).toEqual({
         items: [
           {
@@ -598,7 +598,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         'indexName',
-        hierarchicalMenu.getWidgetSearchParameters!(new SearchParameters(), {
+        hierarchicalMenu.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -634,7 +634,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         'indexName',
-        hierarchicalMenu.getWidgetSearchParameters!(new SearchParameters(), {
+        hierarchicalMenu.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -820,16 +820,13 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
           const helper = algoliasearchHelper(
             createSearchClient(),
             'indexName',
-            hierarchicalMenu.getWidgetSearchParameters!(
-              new SearchParameters(),
-              {
-                uiState: {
-                  hierarchicalMenu: {
-                    category: ['Decoration'],
-                  },
+            hierarchicalMenu.getWidgetSearchParameters(new SearchParameters(), {
+              uiState: {
+                hierarchicalMenu: {
+                  category: ['Decoration'],
                 },
-              }
-            )
+              },
+            })
           );
 
           hierarchicalMenu.init!(createInitOptions({ helper }));
@@ -896,7 +893,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         attributes: ['categoriesLvl0', 'categoriesLvl1'],
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -929,7 +926,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         attributes: ['categoriesLvl0', 'categoriesLvl1'],
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -966,7 +963,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         attributes: ['categoriesLvl0', 'categoriesLvl1'],
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {
           hierarchicalMenu: {
             countryLvl0: ['TopLevelCountry', 'SubLevelCountry'],
@@ -1000,7 +997,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         attributes: ['categoriesLvl0', 'categoriesLvl1'],
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1040,7 +1037,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         attributes: ['categoriesLvl0', 'categoriesLvl1'],
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1067,7 +1064,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         attributes: ['categoriesLvl0', 'categoriesLvl1'],
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           hierarchicalMenu: {
             categoriesLvl0: ['TopLevel', 'SubLevel'],
@@ -1111,7 +1108,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         attributes: ['categoriesLvl0', 'categoriesLvl1'],
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           hierarchicalMenu: {
             categoriesLvl0: ['TopLevel', 'SubLevel'],
@@ -1143,7 +1140,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         separator: ' / ',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1159,7 +1156,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         rootPath: 'TopLevel > SubLevel',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1175,7 +1172,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
         showParentLevel: true,
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1201,7 +1198,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       });
 
       expect(() =>
-        widget.getWidgetSearchParameters!(helper.state, {
+        widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         })
       ).toWarnDev();
@@ -1227,7 +1224,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       });
 
       expect(() =>
-        widget.getWidgetSearchParameters!(helper.state, {
+        widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         })
       ).toWarnDev();
@@ -1253,7 +1250,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       });
 
       expect(() =>
-        widget.getWidgetSearchParameters!(helper.state, {
+        widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         })
       ).toWarnDev();
@@ -1268,7 +1265,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
           attributes: ['categoriesLvl0', 'categoriesLvl1'],
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1284,7 +1281,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
           limit: 5,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1300,7 +1297,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
           showMore: true,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1317,7 +1314,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
           showMoreLimit: 15,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1335,7 +1332,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
           attributes: ['categoriesLvl0', 'categoriesLvl1'],
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1354,7 +1351,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
           limit: 110,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1376,7 +1373,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -1501,7 +1498,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -1618,7 +1615,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hierarchica
       const helper = algoliasearchHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
diff --git a/src/connectors/hierarchical-menu/connectHierarchicalMenu.ts b/src/connectors/hierarchical-menu/connectHierarchicalMenu.ts
index 2b5526f812..792c70ac6c 100644
--- a/src/connectors/hierarchical-menu/connectHierarchicalMenu.ts
+++ b/src/connectors/hierarchical-menu/connectHierarchicalMenu.ts
@@ -324,7 +324,7 @@ const connectHierarchicalMenu: HierarchicalMenuConnector =
               instantSearchInstance,
               helper,
               attribute: hierarchicalFacetName,
-              widgetType: this.$$type!,
+              widgetType: this.$$type,
             });
           }
 
diff --git a/src/connectors/hits-per-page/__tests__/connectHitsPerPage-test.ts b/src/connectors/hits-per-page/__tests__/connectHitsPerPage-test.ts
index bd77fbcd9d..bb15f8c6a3 100644
--- a/src/connectors/hits-per-page/__tests__/connectHitsPerPage-test.ts
+++ b/src/connectors/hits-per-page/__tests__/connectHitsPerPage-test.ts
@@ -116,7 +116,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
     });
 
     expect(
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     ).toEqual(
@@ -244,7 +244,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
     });
 
     expect(
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     ).toEqual(
@@ -265,7 +265,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
     });
 
     expect(
-      widget.getWidgetSearchParameters!(
+      widget.getWidgetSearchParameters(
         new SearchParameters({ hitsPerPage: 20 }),
         { uiState: {} }
       )
@@ -952,7 +952,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
         ],
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -978,7 +978,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
         ],
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -1003,7 +1003,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
         ],
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -1030,7 +1030,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
         ],
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1049,7 +1049,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
         ],
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           hitsPerPage: 22,
         },
@@ -1072,7 +1072,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits-per-pa
         ],
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           hitsPerPage: 33,
         },
diff --git a/src/connectors/hits/__tests__/connectHits-test.ts b/src/connectors/hits/__tests__/connectHits-test.ts
index 367db57061..fbd3e92fe6 100644
--- a/src/connectors/hits/__tests__/connectHits-test.ts
+++ b/src/connectors/hits/__tests__/connectHits-test.ts
@@ -508,8 +508,8 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits/js/#co
 
       expect(renderState2.hits).toEqual({
         hits: expectedHits,
-        sendEvent: renderState1.hits!.sendEvent,
-        bindEvent: renderState1.hits!.bindEvent,
+        sendEvent: renderState1.hits.sendEvent,
+        bindEvent: renderState1.hits.bindEvent,
         results,
         widgetParams: {},
       });
diff --git a/src/connectors/hits/connectHits.ts b/src/connectors/hits/connectHits.ts
index 3409f370c6..8ff79a9686 100644
--- a/src/connectors/hits/connectHits.ts
+++ b/src/connectors/hits/connectHits.ts
@@ -125,14 +125,14 @@ const connectHits: HitsConnector = function connectHits(
           sendEvent = createSendEventForHits({
             instantSearchInstance,
             index: helper.getIndex(),
-            widgetType: this.$$type!,
+            widgetType: this.$$type,
           });
         }
 
         if (!bindEvent) {
           bindEvent = createBindEventForHits({
             index: helper.getIndex(),
-            widgetType: this.$$type!,
+            widgetType: this.$$type,
           });
         }
 
diff --git a/src/connectors/infinite-hits/__tests__/connectInfiniteHits-test.ts b/src/connectors/infinite-hits/__tests__/connectInfiniteHits-test.ts
index 45f9975831..835936ac8e 100644
--- a/src/connectors/infinite-hits/__tests__/connectInfiniteHits-test.ts
+++ b/src/connectors/infinite-hits/__tests__/connectInfiniteHits-test.ts
@@ -942,7 +942,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
       });
       const widget = makeWidget({});
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -965,7 +965,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
         showPrevious: true,
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -986,7 +986,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
         showPrevious: true,
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -1009,7 +1009,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
         showPrevious: true,
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -1103,13 +1103,13 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
       expect(renderState2.infiniteHits).toEqual({
         hits: expectedHits,
         currentPageHits: expectedCurrentPageHits,
-        sendEvent: renderState1.infiniteHits!.sendEvent,
-        bindEvent: renderState1.infiniteHits!.bindEvent,
+        sendEvent: renderState1.infiniteHits.sendEvent,
+        bindEvent: renderState1.infiniteHits.bindEvent,
         isFirstPage: true,
         isLastPage: true,
         results,
-        showMore: renderState1.infiniteHits!.showMore,
-        showPrevious: renderState1.infiniteHits!.showPrevious,
+        showMore: renderState1.infiniteHits.showMore,
+        showPrevious: renderState1.infiniteHits.showPrevious,
         widgetParams: {},
       });
     });
@@ -1215,7 +1215,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
       const helper = algoliasearchHelper(createSearchClient(), 'indexName');
       const widget = makeWidget({});
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1231,7 +1231,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
         escapeHTML: true,
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1247,7 +1247,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
         escapeHTML: false,
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1263,7 +1263,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
         showPrevious: true,
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1278,7 +1278,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
         showPrevious: true,
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           page: 0,
         },
@@ -1295,7 +1295,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/infinite-hi
         showPrevious: true,
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           page: 3,
         },
diff --git a/src/connectors/infinite-hits/connectInfiniteHits.ts b/src/connectors/infinite-hits/connectInfiniteHits.ts
index b0d63a76db..7fc4039f6d 100644
--- a/src/connectors/infinite-hits/connectInfiniteHits.ts
+++ b/src/connectors/infinite-hits/connectInfiniteHits.ts
@@ -296,11 +296,11 @@ const connectInfiniteHits: InfiniteHitsConnector = function connectInfiniteHits(
           sendEvent = createSendEventForHits({
             instantSearchInstance,
             index: helper.getIndex(),
-            widgetType: this.$$type!,
+            widgetType: this.$$type,
           });
           bindEvent = createBindEventForHits({
             index: helper.getIndex(),
-            widgetType: this.$$type!,
+            widgetType: this.$$type,
           });
           isFirstPage =
             helper.state.page === undefined ||
diff --git a/src/connectors/menu/__tests__/connectMenu-test.ts b/src/connectors/menu/__tests__/connectMenu-test.ts
index b0b3a72760..d58bd083be 100644
--- a/src/connectors/menu/__tests__/connectMenu-test.ts
+++ b/src/connectors/menu/__tests__/connectMenu-test.ts
@@ -101,7 +101,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       });
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       ).toEqual(
@@ -127,7 +127,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       });
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       ).toEqual(
@@ -155,7 +155,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       limit: 9,
     });
 
-    const config = widget.getWidgetSearchParameters!(new SearchParameters(), {
+    const config = widget.getWidgetSearchParameters(new SearchParameters(), {
       uiState: {},
     });
     expect(config).toEqual(
@@ -233,7 +233,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -283,7 +283,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -409,7 +409,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -472,7 +472,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!!(new SearchParameters(), {
+      widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       })
     );
@@ -492,7 +492,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       const helper = jsHelper(
         createSearchClient(),
         'indexName',
-        menu.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+        menu.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
       );
 
       const renderState1 = menu.getRenderState(
@@ -500,7 +500,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
         createInitOptions({ helper })
       );
 
-      expect(renderState1.menu!.brand).toEqual({
+      expect(renderState1.menu.brand).toEqual({
         items: [],
         createURL: expect.any(Function),
         refine: expect.any(Function),
@@ -523,7 +523,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       const helper = jsHelper(
         createSearchClient(),
         'indexName',
-        menu.getWidgetSearchParameters!(new SearchParameters(), {
+        menu.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -571,7 +571,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       const helper = jsHelper(
         createSearchClient(),
         'indexName',
-        menu.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+        menu.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
       );
 
       const renderState1 = menu.getWidgetRenderState(
@@ -601,7 +601,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       const helper = jsHelper(
         createSearchClient(),
         'indexName',
-        menu.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+        menu.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
       );
 
       const renderState1 = menu.getWidgetRenderState(
@@ -749,7 +749,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
           const helper = jsHelper(
             createSearchClient(),
             'indexName',
-            menu.getWidgetSearchParameters!(new SearchParameters(), {
+            menu.getWidgetSearchParameters(new SearchParameters(), {
               uiState: {},
             })
           );
@@ -800,7 +800,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       });
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       ).toEqual(
@@ -828,7 +828,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       });
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       ).toEqual(
@@ -857,7 +857,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       });
 
       // When
-      const config = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const config = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
       const helper = jsHelper(createSearchClient(), '', config);
@@ -889,7 +889,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       });
 
       // When
-      const config = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const config = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
       const helper = jsHelper(createSearchClient(), '', config);
@@ -959,7 +959,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       });
 
       // When
-      const config = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const config = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
       const helper = jsHelper(createSearchClient(), '', config);
@@ -1014,7 +1014,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -1042,7 +1042,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -1074,7 +1074,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {
           menu: {
             categories: 'Phone',
@@ -1102,7 +1102,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1135,7 +1135,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1157,7 +1157,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           menu: {
             brand: 'Apple',
@@ -1194,7 +1194,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           menu: {
             brand: 'Apple',
@@ -1221,7 +1221,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
           attribute: 'brand',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1235,7 +1235,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
           limit: 5,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1249,7 +1249,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
           showMore: true,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1264,7 +1264,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
           showMoreLimit: 15,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1280,7 +1280,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
           attribute: 'brand',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1297,7 +1297,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
           limit: 110,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -1318,7 +1318,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       const helper = jsHelper(
         createSearchClient(),
         indexName,
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -1417,7 +1417,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       const helper = jsHelper(
         createSearchClient(),
         indexName,
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -1460,7 +1460,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       const helper = jsHelper(
         createSearchClient(),
         'test',
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -1480,7 +1480,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/#co
       const helper = jsHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
diff --git a/src/connectors/menu/connectMenu.ts b/src/connectors/menu/connectMenu.ts
index f07c67a566..7d713c5bba 100644
--- a/src/connectors/menu/connectMenu.ts
+++ b/src/connectors/menu/connectMenu.ts
@@ -252,7 +252,7 @@ const connectMenu: MenuConnector = function connectMenu(
             instantSearchInstance,
             helper,
             attribute,
-            widgetType: this.$$type!,
+            widgetType: this.$$type,
           });
         }
 
diff --git a/src/connectors/numeric-menu/__tests__/connectNumericMenu-test.ts b/src/connectors/numeric-menu/__tests__/connectNumericMenu-test.ts
index 0e2ca13114..786460e680 100644
--- a/src/connectors/numeric-menu/__tests__/connectNumericMenu-test.ts
+++ b/src/connectors/numeric-menu/__tests__/connectNumericMenu-test.ts
@@ -742,7 +742,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
     test('returns the `uiState` empty', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -758,7 +758,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
 
       helper.addNumericRefinement('numerics', '=', 20);
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -778,7 +778,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
 
       helper.addNumericRefinement('numerics', '>=', 10);
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -798,7 +798,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
 
       helper.addNumericRefinement('numerics', '<=', 20);
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -819,7 +819,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
       helper.addNumericRefinement('numerics', '>=', 10);
       helper.addNumericRefinement('numerics', '<=', 20);
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -840,7 +840,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
       helper.addNumericRefinement('numerics', '>=', 10);
       helper.addNumericRefinement('numerics', '<=', 20);
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {
           numericMenu: {
             numerics2: '27:36',
@@ -865,7 +865,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
     test('returns the `SearchParameters` with the default value', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -884,7 +884,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
 
       helper.addNumericRefinement('numerics', '=', [5, 10]);
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -905,7 +905,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
         .addNumericRefinement('numerics', '>=', [10])
         .addNumericRefinement('numerics', '<=', [20]);
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           numericMenu: {
             numerics: '10',
@@ -928,7 +928,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
     test('returns the `SearchParameters` with the value from `uiState` (only min)', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           numericMenu: {
             numerics: '10:',
@@ -951,7 +951,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
     test('returns the `SearchParameters` with the value from `uiState` (only max)', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           numericMenu: {
             numerics: ':20',
@@ -974,7 +974,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
     test('returns the `SearchParameters` with the value from `uiState` (range)', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           numericMenu: {
             numerics: '10:20',
@@ -998,7 +998,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
     test('returns the `SearchParameters` with the value from `uiState` (exact)', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           numericMenu: {
             numerics: '10',
@@ -1148,8 +1148,8 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/numeric-men
       expect(renderState2.numericMenu).toEqual({
         numerics: {
           createURL: expect.any(Function),
-          refine: renderState1.numericMenu!.numerics.refine,
-          sendEvent: renderState1.numericMenu!.numerics.sendEvent,
+          refine: renderState1.numericMenu.numerics.refine,
+          sendEvent: renderState1.numericMenu.numerics.sendEvent,
           hasNoResults: true,
           items: [
             {
diff --git a/src/connectors/numeric-menu/connectNumericMenu.ts b/src/connectors/numeric-menu/connectNumericMenu.ts
index 8729cd6ac8..6c18f805e7 100644
--- a/src/connectors/numeric-menu/connectNumericMenu.ts
+++ b/src/connectors/numeric-menu/connectNumericMenu.ts
@@ -354,11 +354,11 @@ const connectNumericMenu: NumericMenuConnector = function connectNumericMenu(
         }
 
         return {
-          createURL: connectorState.createURL!(state),
+          createURL: connectorState.createURL(state),
           items: transformItems(prepareItems(state)),
           hasNoResults: results ? results.nbHits === 0 : true,
-          refine: connectorState.refine!,
-          sendEvent: connectorState.sendEvent!,
+          refine: connectorState.refine,
+          sendEvent: connectorState.sendEvent,
           widgetParams,
         };
       },
@@ -372,9 +372,7 @@ function isRefined(
   option: NumericMenuConnectorParamsItem
 ) {
   // @TODO: same as another spot, why is this mixing arrays & elements?
-  const currentRefinements = state.getNumericRefinements(
-    attribute
-  ) as SearchParameters.OperatorList;
+  const currentRefinements = state.getNumericRefinements(attribute);
 
   if (option.start !== undefined && option.end !== undefined) {
     if (option.start === option.end) {
@@ -409,9 +407,7 @@ function getRefinedState(
   const refinedOption = JSON.parse(decodeURI(facetValue));
 
   // @TODO: why is array / element mixed here & hasRefinements; seems wrong?
-  const currentRefinements = resolvedState.getNumericRefinements(
-    attribute
-  ) as SearchParameters.OperatorList;
+  const currentRefinements = resolvedState.getNumericRefinements(attribute);
 
   if (refinedOption.start === undefined && refinedOption.end === undefined) {
     return resolvedState.removeNumericRefinement(attribute);
diff --git a/src/connectors/pagination/__tests__/connectPagination-test.ts b/src/connectors/pagination/__tests__/connectPagination-test.ts
index 134ce13c54..de53d7c469 100644
--- a/src/connectors/pagination/__tests__/connectPagination-test.ts
+++ b/src/connectors/pagination/__tests__/connectPagination-test.ts
@@ -355,7 +355,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/pagination/
     test('returns the `uiState` empty', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -371,7 +371,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/pagination/
 
       helper.setQueryParameter('page', 4);
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -389,7 +389,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/pagination/
     test('returns the `SearchParameters` with the value from `uiState`', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           page: 5,
         },
@@ -406,7 +406,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/pagination/
     test('returns the `SearchParameters` with the default value', () => {
       const [widget, helper] = getInitializedWidget();
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -424,7 +424,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/pagination/
       helper.setPage(200);
       expect(helper.state.page).toBe(200);
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
diff --git a/src/connectors/query-rules/__tests__/connectQueryRules-test.ts b/src/connectors/query-rules/__tests__/connectQueryRules-test.ts
index e280ffecdb..e7caf78d47 100644
--- a/src/connectors/query-rules/__tests__/connectQueryRules-test.ts
+++ b/src/connectors/query-rules/__tests__/connectQueryRules-test.ts
@@ -413,7 +413,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
 
         // Query parameters are initially set in the helper.
         // Therefore, `ruleContexts` should be set.
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
+        expect(helper.state.ruleContexts).toEqual([
           'ais-brand-Samsung',
           'ais-brand-Apple',
           'ais-price-500',
@@ -446,9 +446,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
-          'overriden-rule',
-        ]);
+        expect(helper.state.ruleContexts).toEqual(['overriden-rule']);
         expect(brandFilterSpy).toHaveBeenCalledTimes(1);
         expect(brandFilterSpy).toHaveBeenCalledWith([]);
       });
@@ -475,9 +473,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
         );
 
         // There's no results yet, so no `ruleContexts` should be set.
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(brandFilterSpy).toHaveBeenCalledTimes(0);
         expect(priceFilterSpy).toHaveBeenCalledTimes(0);
 
@@ -502,9 +498,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
         // There are some results with the facets that we track in the
         // widget but the query parameters are not set in the helper.
         // Therefore, no `ruleContexts` should be set.
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(brandFilterSpy).toHaveBeenCalledTimes(0);
         expect(priceFilterSpy).toHaveBeenCalledTimes(0);
 
@@ -542,7 +536,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
 
         // The search state contains the facets that we track,
         // therefore the `ruleContexts` should finally be set.
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
+        expect(helper.state.ruleContexts).toEqual([
           'ais-brand-Samsung',
           'ais-brand-Apple',
           'ais-price-500',
@@ -574,9 +568,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(brandFilterSpy).toHaveBeenCalledTimes(0);
 
         widget.render!(
@@ -597,9 +589,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(brandFilterSpy).toHaveBeenCalledTimes(0);
 
         helper.setState({
@@ -626,9 +616,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
-          'ais-brand-Samsung',
-        ]);
+        expect(helper.state.ruleContexts).toEqual(['ais-brand-Samsung']);
         expect(brandFilterSpy).toHaveBeenCalledTimes(1);
         expect(brandFilterSpy).toHaveBeenCalledWith(['Samsung', 'Apple']);
       });
@@ -650,9 +638,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(priceFilterSpy).toHaveBeenCalledTimes(0);
 
         widget.render!(
@@ -666,9 +652,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(priceFilterSpy).toHaveBeenCalledTimes(0);
 
         helper.setState({
@@ -691,9 +675,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
-          'ais-price-500',
-        ]);
+        expect(helper.state.ruleContexts).toEqual(['ais-price-500']);
         expect(priceFilterSpy).toHaveBeenCalledTimes(1);
         expect(priceFilterSpy).toHaveBeenCalledWith([500, 400, 100]);
       });
@@ -718,9 +700,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(querySpy).toHaveBeenCalledTimes(0);
 
         widget.render!(
@@ -734,9 +714,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(querySpy).toHaveBeenCalledTimes(0);
 
         helper.setState({
@@ -754,9 +732,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
-          'ais-query-cats_are_cool',
-        ]);
+        expect(helper.state.ruleContexts).toEqual(['ais-query-cats_are_cool']);
         expect(querySpy).toHaveBeenCalledTimes(1);
         expect(querySpy).toHaveBeenCalledWith(['cats are cool']);
 
@@ -775,7 +751,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toBeUndefined();
+        expect(helper.state.ruleContexts).toBeUndefined();
         expect(querySpy).toHaveBeenCalledTimes(2);
         expect(querySpy).toHaveBeenCalledWith(['dogs are cool']);
       });
@@ -822,7 +798,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/query-rules
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
+        expect(helper.state.ruleContexts).toEqual([
           'ais-brand-Insignia_',
           'ais-brand-_Apple',
         ]);
@@ -899,10 +875,8 @@ Consider using \`transformRuleContexts\` to minimize the number of rules sent to
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toHaveLength(
-          10
-        );
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
+        expect(helper.state.ruleContexts).toHaveLength(10);
+        expect(helper.state.ruleContexts).toEqual([
           'ais-brand-Insignia',
           'ais-brand-Canon',
           'ais-brand-Dynex',
@@ -959,7 +933,7 @@ Consider using \`transformRuleContexts\` to minimize the number of rules sent to
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
+        expect(helper.state.ruleContexts).toEqual([
           'initial-rule',
           'ais-brand-Samsung',
           'ais-brand-Apple',
@@ -989,9 +963,7 @@ Consider using \`transformRuleContexts\` to minimize the number of rules sent to
           },
         });
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
 
         widget.init!(
           createInitOptions({
@@ -1000,9 +972,7 @@ Consider using \`transformRuleContexts\` to minimize the number of rules sent to
           })
         );
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
-          'ais-brand-Samsung',
-        ]);
+        expect(helper.state.ruleContexts).toEqual(['ais-brand-Samsung']);
         expect(brandFilterSpy).toHaveBeenCalledTimes(1);
         expect(brandFilterSpy).toHaveBeenCalledWith(['Samsung']);
 
@@ -1014,9 +984,7 @@ Consider using \`transformRuleContexts\` to minimize the number of rules sent to
           },
         });
 
-        expect((helper.state as SearchParameters).ruleContexts).toEqual(
-          undefined
-        );
+        expect(helper.state.ruleContexts).toEqual(undefined);
         expect(brandFilterSpy).toHaveBeenCalledTimes(1);
       });
     });
@@ -1072,7 +1040,7 @@ Consider using \`transformRuleContexts\` to minimize the number of rules sent to
           'ais-brand-Samsung',
           'ais-brand-Apple',
         ]);
-        expect((helper.state as SearchParameters).ruleContexts).toEqual([
+        expect(helper.state.ruleContexts).toEqual([
           'initial-rule',
           'transformed-brand-Samsung',
           'transformed-brand-Apple',
diff --git a/src/connectors/range/__tests__/connectRange-test.ts b/src/connectors/range/__tests__/connectRange-test.ts
index aed6dac878..a3f1026460 100644
--- a/src/connectors/range/__tests__/connectRange-test.ts
+++ b/src/connectors/range/__tests__/connectRange-test.ts
@@ -106,7 +106,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       attribute,
     });
 
-    const config = widget.getWidgetSearchParameters!(new SearchParameters(), {
+    const config = widget.getWidgetSearchParameters(new SearchParameters(), {
       uiState: {},
     });
     expect(config).toEqual(
@@ -179,7 +179,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       makeWidget({
         attribute,
         min: 0,
-      }).getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      }).getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     ).toEqual(
       new SearchParameters({
         disjunctiveFacets: [attribute],
@@ -193,7 +193,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       makeWidget({
         attribute,
         max: 100,
-      }).getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      }).getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     ).toEqual(
       new SearchParameters({
         disjunctiveFacets: [attribute],
@@ -208,7 +208,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute,
         min: 0,
         max: 100,
-      }).getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      }).getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     ).toEqual(
       new SearchParameters({
         disjunctiveFacets: [attribute],
@@ -234,7 +234,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -295,7 +295,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -327,7 +327,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
 
     const attribute = 'price';
     const widget = makeWidget({ attribute, min: 0, max: 500 });
-    const configuration = widget.getWidgetSearchParameters!(
+    const configuration = widget.getWidgetSearchParameters(
       new SearchParameters({
         index: 'movie',
       }),
@@ -375,7 +375,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
     helper.search = jest.fn();
 
@@ -434,7 +434,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(createSearchClient(), '');
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { range } = widget.getWidgetRenderState(
@@ -459,7 +459,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(createSearchClient(), '');
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { range } = widget.getWidgetRenderState(
@@ -484,7 +484,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(createSearchClient(), '');
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { range } = widget.getWidgetRenderState(
@@ -509,7 +509,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(createSearchClient(), '');
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { range } = widget.getWidgetRenderState(
@@ -534,7 +534,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(createSearchClient(), '');
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { range } = widget.getWidgetRenderState(
@@ -559,7 +559,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(createSearchClient(), '');
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { range } = widget.getWidgetRenderState(
@@ -587,7 +587,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = createHelper();
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { start } = widget.getWidgetRenderState(
@@ -609,7 +609,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = createHelper();
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
       helper.addNumericRefinement(attribute, '>=', 10);
       helper.addNumericRefinement(attribute, '<=', 100);
@@ -634,7 +634,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = createHelper();
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
       helper.addNumericRefinement(attribute, '>=', 10.9);
       helper.addNumericRefinement(attribute, '<=', 99.1);
@@ -706,7 +706,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -736,7 +736,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -765,7 +765,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -795,7 +795,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute, min: 10 });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -826,7 +826,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -859,7 +859,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '>=', 10);
@@ -892,7 +892,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '>=', 10);
@@ -925,7 +925,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '>=', 10);
@@ -959,7 +959,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '>=', 10);
@@ -993,7 +993,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '>=', 10);
@@ -1025,7 +1025,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '<=', 490);
@@ -1060,7 +1060,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '>=', 20);
@@ -1093,7 +1093,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '>=', 240);
@@ -1123,7 +1123,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -1151,7 +1151,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -1179,7 +1179,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -1207,7 +1207,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const widget = connectRange(rendering)({ attribute });
 
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       helper.addNumericRefinement(attribute, '>=', 10);
@@ -1237,7 +1237,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = createHelper();
       const widget = connectRange(rendering)({ attribute });
       helper.setState(
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} })
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} })
       );
 
       const { refine } = widget.getWidgetRenderState(
@@ -1271,7 +1271,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -1289,7 +1289,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(
         createSearchClient(),
         indexName,
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -1310,7 +1310,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(
         createSearchClient(),
         indexName,
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
@@ -1357,7 +1357,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           helper,
@@ -1384,7 +1384,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           helper,
@@ -1410,7 +1410,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           helper,
@@ -1440,7 +1440,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           helper,
@@ -1471,7 +1471,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           helper,
@@ -1502,7 +1502,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           helper,
@@ -1533,7 +1533,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           helper,
@@ -1564,7 +1564,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {
           range: {
             age: '16:',
@@ -1802,7 +1802,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1828,7 +1828,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -1846,7 +1846,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {
             price: '100:1000',
@@ -1871,7 +1871,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {
             price: '100:',
@@ -1895,7 +1895,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {
             price: ':1000',
@@ -1919,7 +1919,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {},
         },
@@ -1939,7 +1939,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {
             price: 'min:max',
@@ -1961,7 +1961,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {
             price: 'wrong-format',
@@ -1989,7 +1989,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute: 'price',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {
             price: '100:1000',
@@ -2021,7 +2021,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         max: 500,
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {
             price: '0:400',
@@ -2045,7 +2045,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         max: 500,
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           range: {
             price: '-20:600',
@@ -2065,7 +2065,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         attribute,
       });
 
-      const actual = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const actual = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
 
@@ -2086,7 +2086,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         max: 500,
       });
 
-      const actual = widget.getWidgetSearchParameters!(
+      const actual = widget.getWidgetSearchParameters(
         new SearchParameters({
           numericRefinements: {
             price: {
@@ -2125,7 +2125,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         },
       });
 
-      const actual = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const actual = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
 
@@ -2148,7 +2148,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         },
       });
 
-      const actual = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const actual = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
 
@@ -2173,7 +2173,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
         },
       });
 
-      const actual = widget.getWidgetSearchParameters!(new SearchParameters(), {
+      const actual = widget.getWidgetSearchParameters(new SearchParameters(), {
         uiState: {},
       });
 
@@ -2228,7 +2228,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/range-input
       const helper = jsHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       );
diff --git a/src/connectors/rating-menu/__tests__/connectRatingMenu-test.ts b/src/connectors/rating-menu/__tests__/connectRatingMenu-test.ts
index f7f3b5de75..4fec9f8d20 100644
--- a/src/connectors/rating-menu/__tests__/connectRatingMenu-test.ts
+++ b/src/connectors/rating-menu/__tests__/connectRatingMenu-test.ts
@@ -24,7 +24,7 @@ describe('connectRatingMenu', () => {
       ...config,
     });
 
-    const initialConfig = widget.getWidgetSearchParameters!(
+    const initialConfig = widget.getWidgetSearchParameters(
       new SearchParameters({}),
       { uiState: {} }
     );
@@ -383,7 +383,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/rating-menu
         attribute: 'grade',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -410,7 +410,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/rating-menu
         attribute: 'grade',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -441,7 +441,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/rating-menu
         attribute: 'grade',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {
           ratingMenu: {
             rating: 4,
@@ -573,7 +573,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/rating-menu
           createURL: expect.any(Function),
           canRefine: true,
           refine: expect.any(Function),
-          sendEvent: renderState1.ratingMenu!.grade.sendEvent,
+          sendEvent: renderState1.ratingMenu.grade.sendEvent,
           hasNoResults: true,
           widgetParams: {
             attribute: 'grade',
@@ -709,7 +709,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/rating-menu
         attribute: 'grade',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -739,7 +739,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/rating-menu
         attribute: 'grade',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
 
@@ -762,7 +762,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/rating-menu
         attribute: 'grade',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           ratingMenu: {
             grade: 3,
@@ -800,7 +800,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/rating-menu
         attribute: 'grade',
       });
 
-      const actual = widget.getWidgetSearchParameters!(helper.state, {
+      const actual = widget.getWidgetSearchParameters(helper.state, {
         uiState: {
           ratingMenu: {
             grade: 3,
diff --git a/src/connectors/rating-menu/connectRatingMenu.ts b/src/connectors/rating-menu/connectRatingMenu.ts
index bd2bb8f5d0..e1a71a1141 100644
--- a/src/connectors/rating-menu/connectRatingMenu.ts
+++ b/src/connectors/rating-menu/connectRatingMenu.ts
@@ -247,12 +247,12 @@ const connectRatingMenu: RatingMenuConnector = function connectRatingMenu(
     function getRefinedState(state: SearchParameters, facetValue: string) {
       const isRefined = getRefinedStar(state) === Number(facetValue);
 
-      const emptyState = state.resetPage().removeNumericRefinement(attribute!);
+      const emptyState = state.resetPage().removeNumericRefinement(attribute);
 
       if (!isRefined) {
         return emptyState
-          .addNumericRefinement(attribute!, '<=', max)
-          .addNumericRefinement(attribute!, '>=', Number(facetValue));
+          .addNumericRefinement(attribute, '<=', max)
+          .addNumericRefinement(attribute, '>=', Number(facetValue));
       }
       return emptyState;
     }
diff --git a/src/connectors/refinement-list/__tests__/connectRefinementList-test.ts b/src/connectors/refinement-list/__tests__/connectRefinementList-test.ts
index d8b3c4b8cc..b8f086e4b7 100644
--- a/src/connectors/refinement-list/__tests__/connectRefinementList-test.ts
+++ b/src/connectors/refinement-list/__tests__/connectRefinementList-test.ts
@@ -124,7 +124,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       });
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       ).toEqual(
@@ -144,7 +144,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       });
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters(), {
+        widget.getWidgetSearchParameters(new SearchParameters(), {
           uiState: {},
         })
       ).toEqual(
@@ -156,7 +156,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       );
 
       expect(
-        widget.getWidgetSearchParameters!(
+        widget.getWidgetSearchParameters(
           new SearchParameters({ maxValuesPerFacet: 100 }),
           { uiState: {} }
         )
@@ -181,7 +181,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       const helper = jsHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       );
@@ -230,7 +230,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       secondRenderingOptions.toggleShowMore();
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       ).toEqual(
@@ -242,7 +242,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       );
 
       expect(
-        widget.getWidgetSearchParameters!(
+        widget.getWidgetSearchParameters(
           new SearchParameters({ maxValuesPerFacet: 100 }),
           { uiState: {} }
         )
@@ -266,7 +266,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       const helper = jsHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       );
@@ -315,7 +315,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       secondRenderingOptions.toggleShowMore();
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       ).toEqual(
@@ -335,7 +335,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       });
 
       expect(
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       ).toEqual(
@@ -357,7 +357,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       limit: 9,
     });
 
-    const config = widget.getWidgetSearchParameters!(new SearchParameters({}), {
+    const config = widget.getWidgetSearchParameters(new SearchParameters({}), {
       uiState: {},
     });
     expect(config).toEqual(
@@ -462,7 +462,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -529,7 +529,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -584,7 +584,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -640,7 +640,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -695,7 +695,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -756,7 +756,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -817,7 +817,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -881,7 +881,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -986,7 +986,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -1195,7 +1195,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     });
 
     const helper = jsHelper(createSearchClient(), '', {
-      ...widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      ...widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       }),
       maxValuesPerFacet: 10,
@@ -1293,7 +1293,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     });
 
     const helper = jsHelper(createSearchClient(), '', {
-      ...widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      ...widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       }),
       maxValuesPerFacet: 10,
@@ -1389,7 +1389,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -1475,7 +1475,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     });
 
     const helper = jsHelper(createSearchClient(), '', {
-      ...widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      ...widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       }),
       maxValuesPerFacet: 3,
@@ -1566,7 +1566,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -1678,7 +1678,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -1754,7 +1754,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -1856,7 +1856,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     });
 
     const helper = jsHelper(createSearchClient(), '', {
-      ...widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      ...widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       }),
       // Here we simulate that another widget has set some highlight tags
@@ -1962,7 +1962,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     });
 
     const helper = jsHelper(createSearchClient(), '', {
-      ...widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      ...widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       }),
       // Here we simulate that another widget has set some highlight tags
@@ -2065,7 +2065,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
     const helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -2090,7 +2090,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       const helper = jsHelper(
         createSearchClient(),
         indexName,
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       );
@@ -2185,7 +2185,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       const helper = jsHelper(
         createSearchClient(),
         indexName,
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       );
@@ -2276,7 +2276,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -2301,7 +2301,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {},
         {
           searchParameters: helper.state,
@@ -2330,7 +2330,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
         attribute: 'brand',
       });
 
-      const actual = widget.getWidgetUiState!(
+      const actual = widget.getWidgetUiState(
         {
           refinementList: {
             categories: ['Phone', 'Tablet'],
@@ -2459,10 +2459,10 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
               value: 'Samsung',
             },
           ],
-          refine: renderState1.refinementList!.brand.refine,
+          refine: renderState1.refinementList.brand.refine,
           searchForItems: expect.any(Function),
           sendEvent: expect.any(Function),
-          toggleShowMore: renderState1.refinementList!.brand.toggleShowMore,
+          toggleShowMore: renderState1.refinementList.brand.toggleShowMore,
           widgetParams: {
             attribute: 'brand',
           },
@@ -2680,7 +2680,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           const helper = jsHelper(
             createSearchClient(),
             'indexName',
-            refinementList.getWidgetSearchParameters!(new SearchParameters(), {
+            refinementList.getWidgetSearchParameters(new SearchParameters(), {
               uiState: {
                 refinementList: { brand: ['Apple', 'Samsung'] },
               },
@@ -2734,7 +2734,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           attribute: 'brand',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2750,7 +2750,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           limit: 5,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2766,7 +2766,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           showMore: true,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2783,7 +2783,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           showMoreLimit: 15,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2801,7 +2801,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           attribute: 'brand',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2820,7 +2820,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           limit: 110,
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2838,7 +2838,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           operator: 'and',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2863,7 +2863,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           operator: 'and',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2882,7 +2882,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           operator: 'and',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {
             refinementList: {
               brand: ['Apple', 'Samsung'],
@@ -2911,7 +2911,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           operator: 'and',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {
             refinementList: {
               brand: ['Apple', 'Samsung'],
@@ -2935,7 +2935,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           attribute: 'brand',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2959,7 +2959,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           attribute: 'brand',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {},
         });
 
@@ -2977,7 +2977,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           attribute: 'brand',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {
             refinementList: {
               brand: ['Apple', 'Samsung'],
@@ -3005,7 +3005,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
           attribute: 'brand',
         });
 
-        const actual = widget.getWidgetSearchParameters!(helper.state, {
+        const actual = widget.getWidgetSearchParameters(helper.state, {
           uiState: {
             refinementList: {
               brand: ['Apple', 'Samsung'],
@@ -3034,7 +3034,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/refinement-
       const helper = jsHelper(
         createSearchClient(),
         '',
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       );
diff --git a/src/connectors/refinement-list/connectRefinementList.ts b/src/connectors/refinement-list/connectRefinementList.ts
index 134d7f6793..39a8bd987b 100644
--- a/src/connectors/refinement-list/connectRefinementList.ts
+++ b/src/connectors/refinement-list/connectRefinementList.ts
@@ -371,7 +371,7 @@ const connectRefinementList: RefinementListConnector =
               instantSearchInstance,
               helper,
               attribute,
-              widgetType: this.$$type!,
+              widgetType: this.$$type,
             });
 
             triggerRefine = (facetValue) => {
diff --git a/src/connectors/relevant-sort/__tests__/connectRelevantSort-test.ts b/src/connectors/relevant-sort/__tests__/connectRelevantSort-test.ts
index 8be85c658d..825e93909f 100644
--- a/src/connectors/relevant-sort/__tests__/connectRelevantSort-test.ts
+++ b/src/connectors/relevant-sort/__tests__/connectRelevantSort-test.ts
@@ -46,7 +46,7 @@ describe('connectRelevantSort', () => {
     );
     refine(10);
     expect(
-      widget.getWidgetSearchParameters!(helper.state, {
+      widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       }).relevancyStrictness
     ).toEqual(10);
@@ -245,7 +245,7 @@ describe('connectRelevantSort', () => {
       const makeWidget = connectRelevantSort(noop);
       const widget = makeWidget({});
 
-      const widgetUiState = widget.getWidgetUiState!(
+      const widgetUiState = widget.getWidgetUiState(
         {},
         { helper, searchParameters: helper.state }
       );
@@ -264,7 +264,7 @@ describe('connectRelevantSort', () => {
       refine(25);
 
       expect(
-        widget.getWidgetUiState!({}, { helper, searchParameters: helper.state })
+        widget.getWidgetUiState({}, { helper, searchParameters: helper.state })
       ).toEqual({
         relevantSort: 25,
       });
@@ -276,7 +276,7 @@ describe('connectRelevantSort', () => {
       const widget = makeWidget({});
 
       expect(
-        widget.getWidgetUiState!(
+        widget.getWidgetUiState(
           { relevantSort: 25 },
           { helper, searchParameters: helper.state }
         )
@@ -291,7 +291,7 @@ describe('connectRelevantSort', () => {
 
       // applies 30 from searchParameters
       expect(
-        widget.getWidgetUiState!(
+        widget.getWidgetUiState(
           { relevantSort: 25 },
           { helper, searchParameters: helper.state }
         )
@@ -306,7 +306,7 @@ describe('connectRelevantSort', () => {
       const makeWidget = connectRelevantSort(noop);
       const widget = makeWidget({});
 
-      const searchParameters = widget.getWidgetSearchParameters!(
+      const searchParameters = widget.getWidgetSearchParameters(
         new SearchParameters(),
         {
           uiState: {},
@@ -319,7 +319,7 @@ describe('connectRelevantSort', () => {
       const makeWidget = connectRelevantSort(noop);
       const widget = makeWidget({});
 
-      const searchParameters = widget.getWidgetSearchParameters!(
+      const searchParameters = widget.getWidgetSearchParameters(
         new SearchParameters(),
         {
           uiState: {
@@ -342,7 +342,7 @@ describe('connectRelevantSort', () => {
       );
       refine(25);
 
-      const searchParameters = widget.getWidgetSearchParameters!(helper.state, {
+      const searchParameters = widget.getWidgetSearchParameters(helper.state, {
         uiState: {},
       });
       expect(searchParameters.relevancyStrictness).toEqual(25);
@@ -358,7 +358,7 @@ describe('connectRelevantSort', () => {
       );
       refine(25);
 
-      const searchParameters = widget.getWidgetSearchParameters!(
+      const searchParameters = widget.getWidgetSearchParameters(
         new SearchParameters(),
         {
           uiState: {
diff --git a/src/connectors/search-box/__tests__/connectSearchBox-test.ts b/src/connectors/search-box/__tests__/connectSearchBox-test.ts
index cf34f438d6..775aa1792c 100644
--- a/src/connectors/search-box/__tests__/connectSearchBox-test.ts
+++ b/src/connectors/search-box/__tests__/connectSearchBox-test.ts
@@ -348,10 +348,10 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/search-box/
       const renderState2 = searchBox.getRenderState({}, createRenderOptions());
 
       expect(renderState2.searchBox).toEqual({
-        clear: renderState1.searchBox!.clear,
+        clear: renderState1.searchBox.clear,
         isSearchStalled: false,
         query: '',
-        refine: renderState1.searchBox!.refine,
+        refine: renderState1.searchBox.refine,
         widgetParams: {
           queryHook,
         },
diff --git a/src/connectors/sort-by/__tests__/connectSortBy-test.ts b/src/connectors/sort-by/__tests__/connectSortBy-test.ts
index b811e597cb..99d1f678f2 100644
--- a/src/connectors/sort-by/__tests__/connectSortBy-test.ts
+++ b/src/connectors/sort-by/__tests__/connectSortBy-test.ts
@@ -706,7 +706,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/sort-by/js/
 
         const uiState = {};
         const searchParametersBefore = SearchParameters.make(helper.state);
-        const searchParametersAfter = widget.getWidgetSearchParameters!(
+        const searchParametersAfter = widget.getWidgetSearchParameters(
           searchParametersBefore,
           { uiState }
         );
@@ -722,7 +722,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/sort-by/js/
         };
 
         const searchParametersBefore = SearchParameters.make(helper.state);
-        const searchParametersAfter = widget.getWidgetSearchParameters!(
+        const searchParametersAfter = widget.getWidgetSearchParameters(
           searchParametersBefore,
           { uiState }
         );
@@ -741,7 +741,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/sort-by/js/
 
         const uiState = {};
         const searchParametersBefore = new SearchParameters(helper.state);
-        const searchParametersAfter = widget.getWidgetSearchParameters!(
+        const searchParametersAfter = widget.getWidgetSearchParameters(
           searchParametersBefore,
           { uiState }
         );
@@ -764,7 +764,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/sort-by/js/
           ],
         });
 
-        const actual = widget.getWidgetSearchParameters!(
+        const actual = widget.getWidgetSearchParameters(
           new SearchParameters({
             index: 'relevance',
           }),
diff --git a/src/lib/utils/checkIndexUiState.ts b/src/lib/utils/checkIndexUiState.ts
index 1f58a1101f..9123e84b7b 100644
--- a/src/lib/utils/checkIndexUiState.ts
+++ b/src/lib/utils/checkIndexUiState.ts
@@ -156,7 +156,7 @@ ${missingWidgets
     return `- \`${stateParameter}\` needs one of these widgets: ${(
       [] as string[]
     )
-      .concat(...widgets.map((name) => getWidgetNames(name!)))
+      .concat(...widgets.map((name) => getWidgetNames(name)))
       .map((name: string) => `"${name}"`)
       .join(', ')}`;
   })
diff --git a/src/lib/utils/mergeSearchParameters.ts b/src/lib/utils/mergeSearchParameters.ts
index c46790c842..862aca1e6e 100644
--- a/src/lib/utils/mergeSearchParameters.ts
+++ b/src/lib/utils/mergeSearchParameters.ts
@@ -30,7 +30,7 @@ const mergeFacets: Merger = (left, right) =>
   right.facets!.reduce((_, name) => _.addFacet(name), left);
 
 const mergeDisjunctiveFacets: Merger = (left, right) =>
-  right.disjunctiveFacets!.reduce(
+  right.disjunctiveFacets.reduce(
     (_, name) => _.addDisjunctiveFacet(name),
     left
   );
@@ -53,7 +53,7 @@ const mergeHierarchicalFacets: Merger = (left, right) =>
 
 // Merge facet refinements
 const mergeTagRefinements: Merger = (left, right) =>
-  right.tagRefinements!.reduce((_, value) => _.addTagRefinement(value), left);
+  right.tagRefinements.reduce((_, value) => _.addTagRefinement(value), left);
 
 const mergeFacetRefinements: Merger = (left, right) =>
   left.setQueryParameters({
diff --git a/src/widgets/__tests__/index.test.ts b/src/widgets/__tests__/index.test.ts
index 4d5d3e483b..7f80fc13ba 100644
--- a/src/widgets/__tests__/index.test.ts
+++ b/src/widgets/__tests__/index.test.ts
@@ -165,7 +165,7 @@ describe('widgets', () => {
       const widgetInstances = initiateAllWidgets();
 
       widgetInstances.forEach(([name, widget]) =>
-        expect([name, widget.$$type!.substr(0, 4)]).toEqual([name, 'ais.'])
+        expect([name, widget.$$type.substr(0, 4)]).toEqual([name, 'ais.'])
       );
     });
   });
diff --git a/src/widgets/dynamic-widgets/__tests__/dynamic-widgets-test.ts b/src/widgets/dynamic-widgets/__tests__/dynamic-widgets-test.ts
index 7c61419f62..2363018273 100644
--- a/src/widgets/dynamic-widgets/__tests__/dynamic-widgets-test.ts
+++ b/src/widgets/dynamic-widgets/__tests__/dynamic-widgets-test.ts
@@ -161,7 +161,7 @@ describe('dynamicWidgets()', () => {
         }),
       ]);
 
-      indexWidget.init!(createInitOptions({ instantSearchInstance }));
+      indexWidget.init(createInitOptions({ instantSearchInstance }));
 
       // set results to the relevant index, so it renders all children
       instantSearchInstance.mainHelper!.derivedHelpers[0].lastResults =
@@ -172,7 +172,7 @@ describe('dynamicWidgets()', () => {
           createMultiSearchResponse({}).results
         );
 
-      indexWidget.render!(createRenderOptions({ instantSearchInstance }));
+      indexWidget.render(createRenderOptions({ instantSearchInstance }));
 
       await wait(0);
 
@@ -237,7 +237,7 @@ describe('dynamicWidgets()', () => {
         }),
       ]);
 
-      indexWidget.init!(createInitOptions({ instantSearchInstance }));
+      indexWidget.init(createInitOptions({ instantSearchInstance }));
 
       // set results to the relevant index, so it renders all children
       instantSearchInstance.mainHelper!.derivedHelpers[0].lastResults =
@@ -248,7 +248,7 @@ describe('dynamicWidgets()', () => {
           createMultiSearchResponse({}).results
         );
 
-      indexWidget.render!(createRenderOptions({ instantSearchInstance }));
+      indexWidget.render(createRenderOptions({ instantSearchInstance }));
 
       await wait(0);
 
@@ -317,7 +317,7 @@ describe('dynamicWidgets()', () => {
         }),
       ]);
 
-      indexWidget.init!(createInitOptions({ instantSearchInstance }));
+      indexWidget.init(createInitOptions({ instantSearchInstance }));
 
       // set results to the relevant index, so it renders all children
       instantSearchInstance.mainHelper!.derivedHelpers[0].lastResults =
@@ -330,7 +330,7 @@ describe('dynamicWidgets()', () => {
           }).results
         );
 
-      indexWidget.render!(createRenderOptions({ instantSearchInstance }));
+      indexWidget.render(createRenderOptions({ instantSearchInstance }));
 
       await wait(0);
 
@@ -374,7 +374,7 @@ describe('dynamicWidgets()', () => {
           }).results
         );
 
-      indexWidget.render!(createRenderOptions({ instantSearchInstance }));
+      indexWidget.render(createRenderOptions({ instantSearchInstance }));
 
       expect(rootContainer).toMatchInlineSnapshot(`
         <div>
@@ -445,7 +445,7 @@ describe('dynamicWidgets()', () => {
         }),
       ]);
 
-      indexWidget.init!(createInitOptions({ instantSearchInstance }));
+      indexWidget.init(createInitOptions({ instantSearchInstance }));
 
       // set results to the relevant index, so it renders all children
       instantSearchInstance.mainHelper!.derivedHelpers[0].lastResults =
@@ -458,7 +458,7 @@ describe('dynamicWidgets()', () => {
           }).results
         );
 
-      indexWidget.render!(createRenderOptions({ instantSearchInstance }));
+      indexWidget.render(createRenderOptions({ instantSearchInstance }));
 
       await wait(0);
 
@@ -524,7 +524,7 @@ describe('dynamicWidgets()', () => {
         }),
       ]);
 
-      indexWidget.init!(createInitOptions({ instantSearchInstance }));
+      indexWidget.init(createInitOptions({ instantSearchInstance }));
 
       // set results to the relevant index, so it renders all children
       instantSearchInstance.mainHelper!.derivedHelpers[0].lastResults =
@@ -537,7 +537,7 @@ describe('dynamicWidgets()', () => {
           }).results
         );
 
-      indexWidget.render!(createRenderOptions({ instantSearchInstance }));
+      indexWidget.render(createRenderOptions({ instantSearchInstance }));
 
       await wait(0);
 
diff --git a/src/widgets/hits-per-page/__tests__/hits-per-page-test.ts b/src/widgets/hits-per-page/__tests__/hits-per-page-test.ts
index ec48c18830..d7cf9bc4de 100644
--- a/src/widgets/hits-per-page/__tests__/hits-per-page-test.ts
+++ b/src/widgets/hits-per-page/__tests__/hits-per-page-test.ts
@@ -83,7 +83,7 @@ describe('hitsPerPage()', () => {
     });
 
     expect(
-      widgetWithDefaults.getWidgetSearchParameters!(new SearchParameters({}), {
+      widgetWithDefaults.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     ).toEqual(
diff --git a/src/widgets/index/__tests__/index-test.ts b/src/widgets/index/__tests__/index-test.ts
index 24efb605cf..db65a74d2d 100644
--- a/src/widgets/index/__tests__/index-test.ts
+++ b/src/widgets/index/__tests__/index-test.ts
@@ -167,7 +167,8 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
       }).toThrow();
 
       expect(() => {
-        instance.addWidgets(createWidget() as any);
+        // @ts-expect-error
+        instance.addWidgets(createWidget());
       }).toThrowErrorMatchingInlineSnapshot(`
 "The \`addWidgets\` method expects an array of widgets.
 
@@ -434,7 +435,8 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
       }).toThrow();
 
       expect(() => {
-        instance.removeWidgets(createWidget() as any);
+        // @ts-expect-error
+        instance.removeWidgets(createWidget());
       }).toThrowErrorMatchingInlineSnapshot(`
 "The \`removeWidgets\` method expects an array of widgets.
 
diff --git a/src/widgets/index/index.ts b/src/widgets/index/index.ts
index 9744a98917..cd32fe871d 100644
--- a/src/widgets/index/index.ts
+++ b/src/widgets/index/index.ts
@@ -247,7 +247,7 @@ const index = (widgetParams: IndexWidgetParams): IndexWidget => {
     },
 
     createURL(nextState: SearchParameters) {
-      return localInstantSearchInstance!._createURL!({
+      return localInstantSearchInstance!._createURL({
         [indexId]: getLocalWidgetsUiState(localWidgets, {
           searchParameters: nextState,
           helper: helper!,
@@ -432,7 +432,7 @@ const index = (widgetParams: IndexWidgetParams): IndexWidget => {
       // aware of the `searchClient`).
       helper.search = () => {
         if (instantSearchInstance.onStateChange) {
-          instantSearchInstance.onStateChange!({
+          instantSearchInstance.onStateChange({
             uiState: instantSearchInstance.mainIndex.getWidgetUiState({}),
             setUiState: instantSearchInstance.setUiState.bind(
               instantSearchInstance
diff --git a/src/widgets/menu-select/__tests__/menu-select-test.ts b/src/widgets/menu-select/__tests__/menu-select-test.ts
index 6fa2450272..d7bec8ba04 100644
--- a/src/widgets/menu-select/__tests__/menu-select-test.ts
+++ b/src/widgets/menu-select/__tests__/menu-select-test.ts
@@ -111,7 +111,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu-select
         });
 
         helper.setState(
-          widget.getWidgetSearchParameters!(new SearchParameters({}), {
+          widget.getWidgetSearchParameters(new SearchParameters({}), {
             uiState: {
               menu: {
                 amazingBrand: 'algolia',
diff --git a/src/widgets/menu/__tests__/menu-test.ts b/src/widgets/menu/__tests__/menu-test.ts
index 3e5d757f22..4323feb8a0 100644
--- a/src/widgets/menu/__tests__/menu-test.ts
+++ b/src/widgets/menu/__tests__/menu-test.ts
@@ -48,7 +48,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/"
       const helper = jsHelper(createSearchClient(), '');
 
       helper.setState(
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       );
@@ -95,7 +95,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/menu/js/"
       const helper = jsHelper(createSearchClient(), '');
 
       helper.setState(
-        widget.getWidgetSearchParameters!(new SearchParameters({}), {
+        widget.getWidgetSearchParameters(new SearchParameters({}), {
           uiState: {},
         })
       );
diff --git a/src/widgets/numeric-menu/__tests__/numeric-menu-test.ts b/src/widgets/numeric-menu/__tests__/numeric-menu-test.ts
index 375a374ff1..809532c739 100644
--- a/src/widgets/numeric-menu/__tests__/numeric-menu-test.ts
+++ b/src/widgets/numeric-menu/__tests__/numeric-menu-test.ts
@@ -71,7 +71,7 @@ describe('numericMenu()', () => {
     helper = algoliasearchHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     );
 
     jest.spyOn(helper, 'search');
diff --git a/src/widgets/places/__tests__/places-test.ts b/src/widgets/places/__tests__/places-test.ts
index 82076f3549..2e6497a9fc 100644
--- a/src/widgets/places/__tests__/places-test.ts
+++ b/src/widgets/places/__tests__/places-test.ts
@@ -155,7 +155,7 @@ describe('places', () => {
 
         widget.init!(createInitOptions({ helper }));
         // Trigger the initialization of `aroundLatLngViaIP`.
-        widget.getWidgetSearchParameters!(helper.state, { uiState: {} });
+        widget.getWidgetSearchParameters(helper.state, { uiState: {} });
 
         expect(helper.state.aroundLatLngViaIP).toBe(true);
 
@@ -198,7 +198,7 @@ describe('places', () => {
 
         widget.init!(createInitOptions({ helper }));
 
-        const nextSearchParameters = widget.getWidgetSearchParameters!(
+        const nextSearchParameters = widget.getWidgetSearchParameters(
           helper.state,
           {
             uiState: {},
@@ -222,7 +222,7 @@ describe('places', () => {
 
         widget.init!(createInitOptions({ helper }));
 
-        const nextSearchParameters = widget.getWidgetSearchParameters!(
+        const nextSearchParameters = widget.getWidgetSearchParameters(
           helper.state,
           {
             uiState: {
@@ -253,7 +253,7 @@ describe('places', () => {
 
         widget.init!(createInitOptions({ helper }));
 
-        const nextSearchParameters = widget.getWidgetSearchParameters!(
+        const nextSearchParameters = widget.getWidgetSearchParameters(
           helper.state,
           {
             uiState: {
@@ -284,7 +284,7 @@ describe('places', () => {
 
         widget.init!(createInitOptions({ helper }));
 
-        const nextSearchParameters = widget.getWidgetSearchParameters!(
+        const nextSearchParameters = widget.getWidgetSearchParameters(
           helper.state,
           {
             uiState: {},
@@ -318,7 +318,7 @@ describe('places', () => {
           },
         };
 
-        widget.getWidgetSearchParameters!(previousSearchParameters, {
+        widget.getWidgetSearchParameters(previousSearchParameters, {
           uiState,
         });
 
@@ -348,7 +348,7 @@ describe('places', () => {
           0
         );
 
-        widget.getWidgetSearchParameters!(helper.state, {
+        widget.getWidgetSearchParameters(helper.state, {
           uiState: {
             places: {
               query: 'Paris, Île-de-France, France',
@@ -372,7 +372,7 @@ describe('places', () => {
         });
 
         const previousUiState = {};
-        const nextUiState = widget.getWidgetUiState!(previousUiState, {
+        const nextUiState = widget.getWidgetUiState(previousUiState, {
           helper,
           searchParameters: helper.state,
         });
@@ -389,7 +389,7 @@ describe('places', () => {
         });
 
         const previousUiState = {};
-        const nextUiState = widget.getWidgetUiState!(previousUiState, {
+        const nextUiState = widget.getWidgetUiState(previousUiState, {
           helper,
           searchParameters: helper.state,
         });
@@ -422,7 +422,7 @@ describe('places', () => {
         });
 
         const previousUiState = {};
-        const nextUiState = widget.getWidgetUiState!(previousUiState, {
+        const nextUiState = widget.getWidgetUiState(previousUiState, {
           helper,
           searchParameters: helper.state,
         });
@@ -452,7 +452,7 @@ describe('places', () => {
         clearEventListener();
 
         const previousUiState = {};
-        const nextUiState = widget.getWidgetUiState!(previousUiState, {
+        const nextUiState = widget.getWidgetUiState(previousUiState, {
           helper,
           searchParameters: helper.state,
         });
@@ -478,7 +478,7 @@ describe('places', () => {
         clearEventListener();
 
         const previousUiState = {};
-        const nextUiState = widget.getWidgetUiState!(previousUiState, {
+        const nextUiState = widget.getWidgetUiState(previousUiState, {
           helper,
           searchParameters: helper.state,
         });
diff --git a/src/widgets/query-rule-custom-data/query-rule-custom-data.tsx b/src/widgets/query-rule-custom-data/query-rule-custom-data.tsx
index 217e9803c7..16c9276500 100644
--- a/src/widgets/query-rule-custom-data/query-rule-custom-data.tsx
+++ b/src/widgets/query-rule-custom-data/query-rule-custom-data.tsx
@@ -67,7 +67,7 @@ const renderer =
   ({ items }: QueryRulesRenderState) => {
     render(
       <CustomData
-        cssClasses={cssClasses as QueryRuleCustomDataComponentCSSClasses}
+        cssClasses={cssClasses}
         templates={templates}
         items={items}
       />,
diff --git a/src/widgets/rating-menu/__tests__/rating-menu-integration-test.ts b/src/widgets/rating-menu/__tests__/rating-menu-integration-test.ts
index 6d1cafde99..30fbdf7796 100644
--- a/src/widgets/rating-menu/__tests__/rating-menu-integration-test.ts
+++ b/src/widgets/rating-menu/__tests__/rating-menu-integration-test.ts
@@ -21,7 +21,7 @@ function getInitializedWidget() {
   const helper = jsHelper(
     createSearchClient(),
     '',
-    widget.getWidgetSearchParameters!(new SearchParameters({}), {
+    widget.getWidgetSearchParameters(new SearchParameters({}), {
       uiState: {},
     })
   );
diff --git a/src/widgets/rating-menu/__tests__/rating-menu-test.ts b/src/widgets/rating-menu/__tests__/rating-menu-test.ts
index 0113ca8883..ad8b591fd7 100644
--- a/src/widgets/rating-menu/__tests__/rating-menu-test.ts
+++ b/src/widgets/rating-menu/__tests__/rating-menu-test.ts
@@ -55,7 +55,7 @@ describe('ratingMenu()', () => {
     helper = jsHelper(
       createSearchClient(),
       '',
-      widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );
@@ -80,7 +80,7 @@ describe('ratingMenu()', () => {
 
   it('configures the underlying disjunctive facet', () => {
     expect(
-      widget.getWidgetSearchParameters!(new SearchParameters(), { uiState: {} })
+      widget.getWidgetSearchParameters(new SearchParameters(), { uiState: {} })
     ).toEqual(
       new SearchParameters({
         disjunctiveFacets: ['anAttrName'],
@@ -231,7 +231,7 @@ describe('ratingMenu()', () => {
     const _helper = jsHelper(
       createSearchClient(),
       '',
-      _widget.getWidgetSearchParameters!(new SearchParameters({}), {
+      _widget.getWidgetSearchParameters(new SearchParameters({}), {
         uiState: {},
       })
     );