1. How do you configure a store in Redux Toolkit?

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When building large-scale applications, organizing RTK Query API slices properly ensures your codebase remains modular, maintainable, and easy to scale. A good structure helps with team collaboration, reusability, and performance. **1. Use a Feature-Based Approach:** Group endpoints by domain or feature (e.g., usersApi, postsApi) instead of having one massive API slice. **2. Create a Shared Root API:** Define a common createApi instance (with shared baseQuery, headers, and tag types) and extend it with injectEndpoints for modularity. **3. Use Consistent Tagging:** Define clear tagTypes to manage cache invalidation across different slices. **4. Co-locate APIs with Features:** Place API files alongside their corresponding feature components and Redux slices for better discoverability. **5. Keep API Logic Pure:** Avoid adding UI or business logic inside API definitions—use onQueryStarted only for small side effects like optimistic updates. **6. Re-export Hooks:** Only export the generated hooks (e.g., useGetPostsQuery) from each API slice to keep imports clean and maintain encapsulation. **7. Use TypeScript for Strong Typing:** Ensure your endpoints have typed request parameters and responses for better safety and autocompletion. // rootApi.js
import { createApi, fetchBaseQuery } from '@reduxjs/toolkit/query/react';

export const rootApi = createApi({
  reducerPath: 'rootApi',
  baseQuery: fetchBaseQuery({ baseUrl: '/api' }),
  tagTypes: ['User', 'Post'],
  endpoints: () => ({}),
});

// postsApi.js
import { rootApi } from './rootApi';

export const postsApi = rootApi.injectEndpoints({
  endpoints: (builder) => ({
    getPosts: builder.query({
      query: () => '/posts',
      providesTags: ['Post'],
    }),
  }),
});

export const { useGetPostsQuery } = postsApi; This modular approach lets you split endpoints across files, improve code organization, and scale the app as it grows — while keeping all API logic under a consistent root. **- Scalability:** Easily add or modify feature APIs without touching unrelated code. **- Maintainability:** Clear structure improves readability and debugging. **- Modularity:** Independent feature slices allow better code reuse and lazy loading. **- Team Collaboration:** Different teams can safely manage different slices. Following these practices helps large applications stay efficient, organized, and easier to maintain as the codebase evolves.

1. How do you configure a store in Redux Toolkit?

Best Practices for Structuring RTK Query API Slices in Large Applications

1. How do you configure a store in Redux Toolkit?

Best Practices for Structuring RTK Query API Slices in Large Applications

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