thunk-model.ts

import { thunk } from "easy-peasy"; // 👈

const store = createStore<StoreModel>({
  todos: {
    items: ["Install easy-peasy", "Build app", "profit"],
    // 👇renamed
    saved: (state, payload) => {
      state.items.push(payload);
    },
    // 👇our thunk
    save: thunk(async (actions, payload) => {
      await todoService.save(payload);
      actions.saved(payload);
    })
  },
  // ...
});