diff --git a/packages/frontend-core/src/components/grid/stores/ui.ts b/packages/frontend-core/src/components/grid/stores/ui.ts
index 1ef9c42a32..78a0b9c2b0 100644
--- a/packages/frontend-core/src/components/grid/stores/ui.ts
+++ b/packages/frontend-core/src/components/grid/stores/ui.ts
@@ -14,7 +14,7 @@ export interface UIStore {
   focusedCellAPI: Writable<{
     isReadonly: () => boolean
   } | null>
-  selectedRows: Writable<any>
+  selectedRows: Writable<Record<string, boolean>>
   hoveredRowId: Writable<string | null>
   rowHeight: Writable<number>
   previousFocusedRowId: Writable<string | null>