29 Common Mistakes Beginners Make When Using Next.js

Next.js is a powerful framework for building React applications, offering many built-in features that streamline the development process. However, for beginners, there are common mistakes that can hinder the learning process and create roadblocks in the development of their projects. In this tutorial, we will outline 29 Next.js mistakes that beginners often make and provide solutions for each one.

1. Not understanding the difference between server-side rendering and client-side rendering

One of the key features of Next.js is its support for server-side rendering (SSR). Many beginners may not fully understand the difference between SSR and client-side rendering (CSR), leading to confusion and potential issues in their projects. SSR renders the initial HTML on the server before sending it to the client, resulting in faster load times and better SEO performance. On the other hand, CSR generates the page on the client-side using JavaScript, which can result in slower load times and potential SEO issues.

To avoid this mistake, beginners should familiarize themselves with the concept of SSR and understand when to use it in their projects. Next.js makes it easy to implement SSR with its built-in support, so take advantage of this feature to improve the performance of your applications.

1. Not setting up a custom server

Another common mistake that beginners make is not setting up a custom server for their Next.js projects. By default, Next.js provides a built-in server that handles routing and rendering, but in some cases, you may need more customization options that require a custom server setup.

To set up a custom server in Next.js, you can create a server.js file in the root of your project and use the express framework to define your server logic. This allows you to add middleware, custom routing rules, and other advanced features to your Next.js application. Remember to update your package.json file to include the necessary scripts for running your custom server.

1. Using next/link incorrectly

Next.js provides a Link component that simplifies client-side navigation and enhances the user experience in your applications. Beginners often make the mistake of not using the Link component correctly, which can lead to issues with navigation and page loading.

To use the Link component in Next.js, import it from next/link and wrap your anchor (<a>) tags with it, passing the href prop as the target route. This allows Next.js to prefetch the linked page and improve the navigation experience for users. Avoid using plain anchor tags for navigation in your Next.js applications, as this can result in unnecessary page reloads and slower performance.

1. Not using getStaticProps and getServerSideProps for data fetching

Data fetching is a crucial aspect of building dynamic applications, and Next.js provides two methods for fetching data: getStaticProps and getServerSideProps. Beginners may overlook these methods and opt for client-side data fetching, which can result in slower load times and potential SEO issues.

To fetch data in Next.js, use the getStaticProps method for static data that can be precomputed at build time and the getServerSideProps method for dynamic data that needs to be fetched on each request. These methods allow you to pre-render your pages with the necessary data, improving performance and SEO for your applications. Make sure to handle data fetching logic correctly in your Next.js components to optimize the rendering process.

1. Not optimizing images for performance

Images are a common element in web applications, but beginners often overlook image optimization for performance in their Next.js projects. Large or unoptimized images can slow down the loading times of your pages and negatively impact the user experience.

To optimize images in Next.js, use the next/image component, which provides built-in functionality for lazy loading, optimization, and resizing of images. Specify the layout prop to determine the image layout (responsive, fixed, or fill) and use the quality and sizes props to control the image quality and dimensions. Additionally, consider using the Image component from the next/image package for advanced features like blur-up loading and placeholder images.

1. Not handling error pages correctly

Error handling is an essential aspect of web development, but beginners often neglect to handle error pages properly in their Next.js projects. Default error pages can be generic and provide a poor user experience, so it’s crucial to customize error pages for a better user experience.

To handle error pages in Next.js, create custom error pages in the pages/_error.js file, which allows you to define custom error handling logic and render specific error messages for different status codes. You can also use the ErrorBoundary component from the next/error package to catch errors and display custom error messages in your Next.js applications. Customize error pages to provide clear, informative feedback to users and improve the overall user experience.

1. Not using environment variables

Environment variables are a useful tool for managing configuration settings and sensitive information in your Next.js projects. Beginners often make the mistake of hardcoding configuration values, which can lead to security vulnerabilities and deployment issues.

To use environment variables in Next.js, create a .env file in the root of your project and define your environment variables using the NEXT_PUBLIC_ prefix for client-side variables and the NEXT_ prefix for server-side variables. Access environment variables in your Next.js components using the process.env object, which allows you to access configuration values securely and manage sensitive information effectively. Remember to secure your environment variables and avoid committing them to version control to prevent security risks.

1. Not optimizing performance with code splitting and lazy loading

Performance optimization is crucial for web applications, but beginners often overlook code splitting and lazy loading techniques in their Next.js projects. Large bundles of JavaScript can slow down the loading times of your pages, leading to a poor user experience.

To optimize performance in Next.js, use code splitting techniques to split your JavaScript bundles into smaller chunks that are loaded only when needed. Use dynamic imports (import()) to lazy load components, libraries, and routes in your Next.js applications, reducing the initial load times and improving the performance of your pages. Take advantage of Next.js’s built-in support for dynamic imports and code splitting to optimize the loading process and create faster, more responsive applications.

1. Not using TypeScript for type safety

Type safety is an important aspect of modern web development, but beginners often overlook TypeScript integration in their Next.js projects. TypeScript provides static typing and improved code quality, helping to catch errors early in the development process and enhance the overall maintainability of your codebase.

To use TypeScript in Next.js, install the necessary dependencies (typescript, @types/react, @types/node) and create a tsconfig.json file in the root of your project to configure TypeScript settings. Use TypeScript interfaces, types, and generics to define the shape of your data structures and ensure type safety throughout your Next.js components. Take advantage of TypeScript’s features like type inference, strict mode, and strict null checks to catch errors and improve code quality in your applications.

1. Not using serverless functions for backend logic

Serverless functions are a powerful tool for building backend logic in Next.js applications, but beginners often overlook this feature and opt for traditional server setups. Serverless functions allow you to run server-side code in response to HTTP requests without managing servers or infrastructure, making it easy to build scalable and cost-effective backend services.

To use serverless functions in Next.js, create API routes in the pages/api directory of your project, defining serverless functions that handle HTTP requests and return JSON responses. Use the req and res objects to access request and response data in your serverless functions and leverage the built-in support for serverless functions in the Next.js framework. Deploy serverless functions to platforms like Vercel, AWS Lambda, or Netlify to run backend logic in a serverless environment and build dynamic, responsive applications with Next.js.

1. Not understanding the Next.js data fetching lifecycle

Next.js provides a robust data fetching lifecycle that allows you to fetch data at various points in the rendering process, but beginners may not fully understand how this works. The getInitialProps, getStaticProps, and getServerSideProps methods all play a role in data fetching in Next.js, each serving a different purpose depending on the data requirements of your application.

To understand the Next.js data fetching lifecycle, familiarize yourself with the differences between getInitialProps, getStaticProps, and getServerSideProps, and when to use each method based on your data fetching needs. Use getInitialProps for universal data fetching in both client-side and server-side rendering, getStaticProps for pre-rendering static data at build time, and getServerSideProps for server-side rendering of dynamic data on each request. Choose the appropriate data fetching method based on the requirements of your application to optimize performance, improve SEO, and enhance the user experience in your Next.js projects.

1. Not optimizing routes and navigation

Routes and navigation are fundamental aspects of web applications, but beginners may overlook route optimization techniques in their Next.js projects. Routing plays a crucial role in the user experience of your applications, impacting page load times, user engagement, and SEO performance.

To optimize routes and navigation in Next.js, use dynamic routing to create flexible, parameterized routes that can handle dynamic data and content. Leverage the Link component for client-side navigation, prefetching linked pages to improve the navigation experience for users. Implement navigation techniques like breadcrumbs, pagination, and deep linking to enhance the usability of your Next.js applications and provide a seamless browsing experience for users.

1. Not handling layout and styling effectively

Layout and styling are essential aspects of web development, but beginners may struggle with handling layout and styling in their Next.js projects. Effective layout and styling techniques can improve the visual appeal and usability of your applications, creating a better user experience for your visitors.

To handle layout and styling in Next.js, use CSS-in-JS solutions like styled-components, emotion, or @emotion/styled to define component styles directly in your JavaScript code. Leverage CSS frameworks like Tailwind CSS, Bootstrap, or Bulma to streamline the styling process and create responsive, visually appealing layouts for your Next.js applications. Organize your styles using component-based styling techniques, separating concerns and improving code maintainability in your projects.

1. Not optimizing for SEO

SEO (Search Engine Optimization) is crucial for ensuring that your Next.js applications rank well in search engine results and drive organic traffic to your website. Beginners often overlook SEO optimization techniques, missing out on valuable opportunities to increase visibility and reach a larger audience.

To optimize your Next.js applications for SEO, follow best practices like using descriptive page titles, meta descriptions, and structured data to improve the visibility of your content in search engine results. Implement server-side rendering (SSR) to improve crawlability and indexability by search engines, ensuring that your content is accessible to search engine bots and optimized for SEO performance. Monitor and analyze your website’s SEO performance using tools like Google Search Console and Google Analytics to track keyword rankings, traffic trends, and user engagement metrics, adjusting your SEO strategy accordingly to improve the visibility and reach of your Next.js applications.

1. Not optimizing for accessibility

Accessibility is a critical aspect of web development, ensuring that your Next.js applications are inclusive and usable for all users, including those with disabilities. Beginners may not prioritize accessibility in their projects, overlooking important accessibility considerations that can impact the user experience and compliance with web accessibility standards.

To optimize your Next.js applications for accessibility, follow best practices like providing alternative text for images, using semantic HTML elements for better screen reader support, and ensuring keyboard navigation and focus management for interactive elements. Leverage accessibility tools like axe or react-axe to test and audit your applications for accessibility issues, identifying and addressing common accessibility barriers that can hinder user interaction and navigation. Follow the Web Content Accessibility Guidelines (WCAG) to ensure that your Next.js applications meet accessibility standards and provide a better user experience for all visitors.

1. Not optimizing for performance

Performance optimization is crucial for delivering fast and responsive web applications, but beginners may not prioritize performance optimization in their Next.js projects. Slow load times, high latency, and poor responsiveness can negatively impact the user experience and discourage visitors from engaging with your applications.

To optimize performance in Next.js, follow best practices like code splitting, lazy loading, and image optimization to reduce the size of your bundles and improve the loading times of your pages. Use server-side rendering (SSR) and client-side hydration to preload and render critical content on the server before sending it to the client, reducing initial load times and improving perceived performance for users. Monitor performance metrics like page load times, time to interactive, and first contentful paint using tools like Lighthouse, WebPageTest, or Chrome DevTools to identify performance bottlenecks and optimize your Next.js applications for speed and responsiveness.

1. Not using version control

Version control is a fundamental best practice in software development, allowing you to track changes, collaborate with team members, and revert to previous versions of your codebase when needed. Beginners may not use version control effectively in their Next.js projects, leading to issues with code organization, collaboration, and deployment.

To use version control in Next.js, initialize a Git repository in the root of your project and commit your code changes regularly using descriptive commit messages to track the evolution of your codebase. Create feature branches for new features or bug fixes, branching off from the main master branch to isolate changes and collaborate with team members on specific tasks. Use version control platforms like GitHub, GitLab, or Bitbucket to host your repositories remotely, providing backup, collaboration, and deployment options for your Next.js projects.

1. Not testing code properly

Testing is an essential aspect of software development, ensuring that your Next.js applications are free of bugs, errors, and regressions that could impact the user experience. Beginners may struggle with testing code effectively in their projects, leading to issues with code quality, reliability, and maintainability.

To test code in Next.js, leverage testing frameworks like Jest, React Testing Library, or Cypress to write unit tests, integration tests, and end-to-end tests for your components, pages, and features. Use test runners like jest or react-scripts to run your tests locally, automating the testing process and validating the behavior of your Next.js applications against expected outcomes. Follow test-driven development (TDD) practices to write tests before implementing new features or changes, ensuring that your code conforms to requirements and specifications throughout the development process.

1. Not handling state management effectively

State management is a critical aspect of building complex web applications, allowing you to manage and synchronize the state of your components, pages, and features in Next.js projects. Beginners may struggle with state management techniques like useState, useReducer, or global state management solutions like Redux or Context API, leading to issues with data flow, reactivity, and synchronization in their applications.

To handle state management in Next.js, use React’s built-in state management hooks like useState and useReducer to manage component-level state and trigger re-renders based on state changes. Leverage global state management solutions like Redux, MobX, or Context API to manage application-level state and handle complex data sharing and synchronization between components and pages. Use state management libraries and tools to simplify state management logic, optimize data flow, and improve code maintainability in your Next.js projects.

1. Not optimizing for mobile devices

Mobile responsiveness is crucial for ensuring that your Next.js applications are accessible and usable across a wide range of devices and screen sizes, but beginners may overlook mobile optimization techniques in their projects. Mobile users represent a significant portion of web traffic, so optimizing for mobile devices is essential for reaching a diverse audience and providing a seamless user experience on smartphones and tablets.

To optimize your Next.js applications for mobile devices, follow best practices like using responsive design techniques, media queries, and viewport meta tags to adapt your layouts and styles to different screen sizes and resolutions. Test your applications on various devices and emulators to ensure that they display correctly and function smoothly on mobile devices, identifying and addressing any issues with layout, navigation, or performance that may impact the user experience. Prioritize mobile optimization in your Next.js projects to reach a wider audience and create a better user experience for mobile users.

1. Not following best practices for security

Security is a critical consideration in web development, ensuring that your Next.js applications are protected against security threats, vulnerabilities, and data breaches. Beginners may not follow best practices for security in their projects, leading to issues with data privacy, user authentication, and authorization that can compromise the integrity and confidentiality of their applications.

To follow best practices for security in Next.js, implement authentication and authorization mechanisms like JWT, OAuth, or sessions to protect your applications from unauthorized access and secure sensitive data. Use HTTPS encryption to encrypt data transmission between clients and servers, preventing eavesdropping and man-in-the-middle attacks that can compromise data integrity and confidentiality. Sanitize user input, validate data, and escape output to prevent cross-site scripting (XSS) attacks, SQL injection, and other security vulnerabilities that can expose your applications to malicious actors. Audit and monitor your applications for security vulnerabilities using tools like OWASP ZAP, Nmap, or Burp Suite to identify and address potential security risks, protecting your Next.js applications from cybersecurity threats and breaches.

1. Not optimizing for internationalization and localization

Internationalization (i18n) and localization (l10n) are important considerations for building multilingual and globally accessible Next.js applications, but beginners may not prioritize i18n and l10n features in their projects. Supporting multiple languages and regions in your applications can expand your reach and appeal to a diverse audience, enhancing the user experience for users worldwide.

To optimize your Next.js applications for internationalization and localization, use i18n libraries and tools like react-intl, i18next, or @formatjs to manage translations, locale data, and language switching in your components and pages. Define localized text, strings, and formats using localization files or JSON objects to provide content in multiple languages and regions, catering to a global audience and improving accessibility for non-English speakers. Implement language detection, content negotiation, and locale switching features to enable users to select their preferred language and region, customizing the user experience based on their language preferences and cultural background. Prioritize internationalization and localization in your Next.js projects to create inclusive, accessible applications that resonate with users worldwide.

1. Not optimizing for performance

2. Not optimizing for accessibility

3. Not following best practices for security

4. Not optimizing for internationalization and localization

5. Not prioritizing user experience

6. Not following coding standards and conventions

7. Not seeking help and asking questions

In conclusion, these are some of the common mistakes that beginners make while working with Next.js. By following the solutions and best practices outlined in this tutorial, you can avoid these pitfalls and build high-quality Next.js applications that are performant, accessible, secure, and user-friendly. Remember to prioritize learning, experimentation, and continuous improvement in your Next.js projects to enhance your skills and deliver exceptional web experiences for your users. Happy coding!