diff --git a/config/tsconfig.base.json b/config/tsconfig.base.json
index 326841c8574a4a..e837746b45bb24 100644
--- a/config/tsconfig.base.json
+++ b/config/tsconfig.base.json
@@ -40,6 +40,7 @@
     "noImplicitThis": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
+    "noUncheckedIndexedAccess": true,
     "strict": true,
     "strictBindCallApply": false,
     "useUnknownInCatchVariables": false,
diff --git a/static/app/components/avatarUploader.tsx b/static/app/components/avatarUploader.tsx
index 472f4c78bfd531..da52b2c89ff02d 100644
--- a/static/app/components/avatarUploader.tsx
+++ b/static/app/components/avatarUploader.tsx
@@ -226,7 +226,7 @@ class AvatarUploader extends Component<Props, State> {
       getDiffSW,
     } as const;
 
-    const diff = helpers['getDiff' + resizeDirection!.toUpperCase()](yDiff, xDiff);
+    const diff = helpers['getDiff' + resizeDirection!.toUpperCase()]!(yDiff, xDiff);
 
     let height = container.clientHeight - oldDimensions.top;
     let width = container.clientWidth - oldDimensions.left;
diff --git a/static/app/views/issueList/groupSearchViewTabs/issueViewTab.tsx b/static/app/views/issueList/groupSearchViewTabs/issueViewTab.tsx
index 44a6c8e22fe608..20636e1ee9567e 100644
--- a/static/app/views/issueList/groupSearchViewTabs/issueViewTab.tsx
+++ b/static/app/views/issueList/groupSearchViewTabs/issueViewTab.tsx
@@ -74,7 +74,7 @@ export function IssueViewTab({
     dispatch({type: 'DELETE_VIEW', syncViews: true});
     // Including this logic in the dispatch call breaks the tests for some reason
     // so we're doing it here instead
-    tabListState?.setSelectedKey(tabs.filter(tb => tb.key !== tab.key)[0].key);
+    tabListState?.setSelectedKey(tabs.filter(tb => tb.key !== tab.key)[0]!.key);
   };
 
   const makeMenuOptions = (tab: IssueView): MenuItemProps[] => {
diff --git a/static/app/views/issueList/groupSearchViewTabs/issueViews.tsx b/static/app/views/issueList/groupSearchViewTabs/issueViews.tsx
index 265117fafc9a18..f21af8a544699a 100644
--- a/static/app/views/issueList/groupSearchViewTabs/issueViews.tsx
+++ b/static/app/views/issueList/groupSearchViewTabs/issueViews.tsx
@@ -539,7 +539,7 @@ export function IssueViewsStateProvider({
         return;
       }
       setNewViewActive(false);
-      const {label, query: newQuery, saveQueryToView} = newViews[0];
+      const {label, query: newQuery, saveQueryToView} = newViews[0]!;
       const remainingNewViews: IssueView[] = newViews.slice(1)?.map(view => {
         const newId = generateTempViewId();
         const viewToTab: IssueView = {
diff --git a/static/app/views/issueList/issueViewsHeader.tsx b/static/app/views/issueList/issueViewsHeader.tsx
index cd91ed968b2b05..bd554b5a27d37a 100644
--- a/static/app/views/issueList/issueViewsHeader.tsx
+++ b/static/app/views/issueList/issueViewsHeader.tsx
@@ -202,14 +202,14 @@ function IssueViewsIssueListHeaderTabsContent({
           ...location,
           query: {
             ...queryParamsWithPageFilters,
-            query: views[0].query,
-            sort: views[0].querySort,
-            viewId: views[0].id,
+            query: views[0]!.query,
+            sort: views[0]!.querySort,
+            viewId: views[0]!.id,
           },
         }),
         {replace: true}
       );
-      tabListState?.setSelectedKey(views[0].key);
+      tabListState?.setSelectedKey(views[0]!.key);
       return;
     }
     // if a viewId is present, check if it exists in the existing views.
@@ -372,7 +372,7 @@ function IssueViewsIssueListHeaderTabsContent({
       ? views.find(tab => tab.id === viewId)!.key
       : query
         ? TEMPORARY_TAB_KEY
-        : views[0].key;
+        : views[0]!.key;
 
   return (
     <DraggableTabList
diff --git a/static/app/views/performance/table.tsx b/static/app/views/performance/table.tsx
index a88bbf69a39433..3cde9231804882 100644
--- a/static/app/views/performance/table.tsx
+++ b/static/app/views/performance/table.tsx
@@ -477,7 +477,7 @@ class _Table extends Component<Props, State> {
   renderHeadCellWithMeta = (tableMeta: TableData['meta']) => {
     const columnTitles = this.props.columnTitles ?? COLUMN_TITLES_OPTIONAL_TOOLTIP;
     return (column: TableColumn<keyof TableDataRow>, index: number): React.ReactNode =>
-      this.renderHeadCell(tableMeta, column, columnTitles[index]);
+      this.renderHeadCell(tableMeta, column, columnTitles[index]!);
   };
 
   renderPrependCellWithData = (tableData: TableData | null) => {
diff --git a/static/app/views/performance/transactionSummary/transactionSpans/spanMetricsTable.tsx b/static/app/views/performance/transactionSummary/transactionSpans/spanMetricsTable.tsx
index 45d7209ccc1be4..ac00a479b27935 100644
--- a/static/app/views/performance/transactionSummary/transactionSpans/spanMetricsTable.tsx
+++ b/static/app/views/performance/transactionSummary/transactionSpans/spanMetricsTable.tsx
@@ -168,6 +168,9 @@ export default function SpanMetricsTable(props: Props) {
                 location,
                 sort,
               }),
+            // This is now caught by noUncheckedIndexedAccess, ignoring for now as
+            // it seems related to some nasty grid editable generic.
+            // @ts-ignore
             renderBodyCell: renderBodyCell(
               location,
               organization,
diff --git a/static/app/views/performance/transactionSummary/transactionSpans/spanSummary/spanSummaryTable.tsx b/static/app/views/performance/transactionSummary/transactionSpans/spanSummary/spanSummaryTable.tsx
index 9c4bbfb0b1cd73..0b25cc89b0dd46 100644
--- a/static/app/views/performance/transactionSummary/transactionSpans/spanSummary/spanSummaryTable.tsx
+++ b/static/app/views/performance/transactionSummary/transactionSpans/spanSummary/spanSummaryTable.tsx
@@ -251,6 +251,9 @@ export default function SpanSummaryTable(props: Props) {
                 location,
                 sort,
               }),
+            // This is now caught by noUncheckedIndexedAccess, ignoring for now as
+            // it seems related to some nasty grid editable generic.
+            // @ts-ignore
             renderBodyCell: renderBodyCell(
               location,
               organization,