diff --git a/packages/omniviewdev-runtime/src/hooks/resource/useEventBatcher.test.ts b/packages/omniviewdev-runtime/src/hooks/resource/useEventBatcher.test.ts
index 0bd10871..34185848 100644
--- a/packages/omniviewdev-runtime/src/hooks/resource/useEventBatcher.test.ts
+++ b/packages/omniviewdev-runtime/src/hooks/resource/useEventBatcher.test.ts
@@ -126,6 +126,25 @@ describe('applyBatch', () => {
     expect(result.success).toBe(true);
   });
 
+  it('handles class instances (non-plain objects) as oldData', () => {
+    class ListResult {
+      result: any[];
+      success: boolean;
+      totalCount: number;
+      constructor() {
+        this.result = [makeItem('pod-1')];
+        this.success = true;
+        this.totalCount = 1;
+      }
+    }
+    const classData = new ListResult();
+    const events: ResourceEvent[] = [
+      { type: 'ADD', payload: { data: makeItem('pod-2'), key: 'k', connection: 'c', id: 'pod-2', namespace: 'default' } },
+    ];
+    const result = applyBatch(classData, events, idAccessor);
+    expect(result.result).toHaveLength(2);
+  });
+
   it('supports nested id accessor paths', () => {
     const deepAccessor = 'spec.id';
     const data = {
diff --git a/packages/omniviewdev-runtime/src/hooks/resource/useEventBatcher.ts b/packages/omniviewdev-runtime/src/hooks/resource/useEventBatcher.ts
index aee34d4b..32d62e53 100644
--- a/packages/omniviewdev-runtime/src/hooks/resource/useEventBatcher.ts
+++ b/packages/omniviewdev-runtime/src/hooks/resource/useEventBatcher.ts
@@ -1,6 +1,5 @@
 import { useCallback, useEffect, useRef } from 'react';
 import type { QueryClient, QueryKey } from '@tanstack/react-query';
-import { produce } from 'immer';
 import get from 'lodash.get';
 import type { WatchState } from '../../types/watch';
 
@@ -37,6 +36,9 @@ export type ResourceEvent =
 /**
  * Apply a batch of resource events to a list query cache entry.
  * Extracted for testability — this is the core batching logic.
+ *
+ * Returns a new plain object (immutable-style) without relying on Immer,
+ * avoiding issues with Wails binding class instances that Immer cannot draft.
  */
 export function applyBatch(
   oldData: any,
@@ -44,39 +46,38 @@ export function applyBatch(
   idAccessor: string,
 ): any {
   const base = oldData ?? { result: [], success: true, totalCount: 0 };
-  return produce(base, (draft: any) => {
-    for (const event of events) {
-      switch (event.type) {
-        case 'ADD': {
-          const idx = draft.result.findIndex(
-            (item: any) => get(event.payload.data, idAccessor) === get(item, idAccessor),
-          );
-          if (idx === -1) {
-            draft.result.push(event.payload.data);
-          }
-          break;
+  // Shallow-copy the result array so we never mutate the cached version.
+  const result = [...(base.result ?? [])];
+
+  for (const event of events) {
+    const eventId = get(event.payload.data, idAccessor);
+
+    switch (event.type) {
+      case 'ADD': {
+        const idx = result.findIndex((item: any) => get(item, idAccessor) === eventId);
+        if (idx === -1) {
+          result.push(event.payload.data);
         }
-        case 'UPDATE': {
-          const idx = draft.result.findIndex(
-            (item: any) => get(event.payload.data, idAccessor) === get(item, idAccessor),
-          );
-          if (idx !== -1) {
-            draft.result[idx] = event.payload.data;
-          }
-          break;
+        break;
+      }
+      case 'UPDATE': {
+        const idx = result.findIndex((item: any) => get(item, idAccessor) === eventId);
+        if (idx !== -1) {
+          result[idx] = event.payload.data;
         }
-        case 'DELETE': {
-          const idx = draft.result.findIndex(
-            (item: any) => get(event.payload.data, idAccessor) === get(item, idAccessor),
-          );
-          if (idx !== -1) {
-            draft.result.splice(idx, 1);
-          }
-          break;
+        break;
+      }
+      case 'DELETE': {
+        const idx = result.findIndex((item: any) => get(item, idAccessor) === eventId);
+        if (idx !== -1) {
+          result.splice(idx, 1);
         }
+        break;
       }
     }
-  });
+  }
+
+  return { ...base, result };
 }
 
 /**
diff --git a/packages/omniviewdev-runtime/src/hooks/resource/useWatchState.ts b/packages/omniviewdev-runtime/src/hooks/resource/useWatchState.ts
index 61e4a296..5dca8eae 100644
--- a/packages/omniviewdev-runtime/src/hooks/resource/useWatchState.ts
+++ b/packages/omniviewdev-runtime/src/hooks/resource/useWatchState.ts
@@ -1,8 +1,6 @@
 import { useCallback, useEffect, useRef } from 'react';
 import { useQuery, useQueryClient } from '@tanstack/react-query';
-import { produce } from 'immer';
-
-import { GetWatchState } from '../../bindings/github.com/omniviewdev/omniview/backend/pkg/plugin/resource/servicewrapper';
+import { GetWatchState} from '../../bindings/github.com/omniviewdev/omniview/backend/pkg/plugin/resource/servicewrapper';
 import { Events } from '@wailsio/runtime';
 import { useResolvedPluginId } from '../useResolvedPluginId';
 import type {
@@ -43,20 +41,19 @@ export const useWatchState = ({
   const applyEvent = useCallback((event: WatchStateEvent) => {
     queryClient.setQueryData<WatchConnectionSummary>(queryKey, (old) => {
       if (!old) return old;
-      return produce(old, (draft) => {
-        draft.resources[event.resourceKey] = event.state;
-        draft.resourceCounts[event.resourceKey] = event.resourceCount;
-
-        // Recompute aggregates
-        let synced = 0;
-        let errors = 0;
-        for (const state of Object.values(draft.resources)) {
-          if (state === WatchState.WatchStateSynced) synced++;
-          if (state === WatchState.WatchStateError || state === WatchState.WatchStateFailed) errors++;
-        }
-        draft.syncedCount = synced;
-        draft.errorCount = errors;
-      });
+
+      const resources = { ...old.resources, [event.resourceKey]: event.state };
+      const resourceCounts = { ...old.resourceCounts, [event.resourceKey]: event.resourceCount };
+
+      // Recompute aggregates
+      let synced = 0;
+      let errors = 0;
+      for (const state of Object.values(resources)) {
+        if (state === WatchState.WatchStateSynced) synced++;
+        if (state === WatchState.WatchStateError || state === WatchState.WatchStateFailed) errors++;
+      }
+
+      return { ...old, resources, resourceCounts, totalResources: Object.keys(resources).length, syncedCount: synced, errorCount: errors };
     });
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [queryClient, pluginID, connectionID]);