Redux Toolkit vs Zustand: which is better for global state management in a Next.js e-commerce app?

I am building an e-commerce application with Next.js and I need to manage global state for features like cart, user authentication, and product listings.

I have experience with both Redux Toolkit and Zustand but I am unsure which one is the better choice for a production-level app.

With Redux Toolkit I created a cartSlice using createSlice and configured the store like this:

const cartSlice = createSlice({
  name: "cart",
  initialState: { cartItems: [] },
  reducers: {
    addToCart: (state, action) => {
      state.cartItems.push(action.payload);
    },
  },
});

With Zustand I created a store directly like this:

const useStore = create((set) => ({
  cartItems: [],
  addToCart: (item) =>
    set((state) => ({ cartItems: [...state.cartItems, item] })),
}));

Both work fine for basic use cases but I have some concerns:

1. Which one scales better for large applications?

2. Which one has better TypeScript support?

3. Is Redux Toolkit overkill for a mid-size Next.js project?

4. Does Zustand have any limitations for complex state logic?

I would love to hear from developers who have used both in production and what their experience has been.