React is undoubtedly the most popular JavaScript framework for building modern web applications. With its component-based architecture, declarative programming approach, and extensive ecosystem of tools and libraries, React simplifies front-end development significantly.

However, React applications have traditionally relied on client-side rendering, where the entire UI is rendered in the browser. This leads to poor page load performance and SEO issues.

Enter Next.js – the popular React framework that provides server side rendering (SSR) out of the box, solving these problems. In this post, we’ll understand what SSR is, why it matters, and how Next.js implements it seamlessly.

What is Server Side Rendering (SSR)?

With traditional client-side rendered (CSR) apps, an empty HTML shell is served to the browser first. Then the entire JavaScript application is downloaded, parsed, and executed before the UI is rendered.

This leads to 2 major drawbacks:

  1. Poor Page Load Performance – Users stare at a blank screen until the JavaScript executes. This leads to slow first load times.
  2. Negative Impact on SEO – Search engine crawlers have trouble indexing the content inside a CSR application. This negatively impacts rankings and visibility.

React Js Server side rendering solves both these issues by pre-rendering the HTML on the server instead of the client.

So with ReactJs SSR, the server sends a fully rendered HTML page that is ready to be consumed by the browser. The client-side JavaScript then takes over and handles any further interactions.

This offers 2 key benefits:

  1. Faster Page Loads – Users no longer have to stare at blank screens as the HTML is delivered instantly. This significantly improves user experience.
  2. SEO Friendly – Search engines now see a fully rendered HTML page that they can crawl easily for better content indexing.

In summary, SSR React shifts the initial rendering job from client to server, eliminating performance bottlenecks and SEO issues.

SSR with Next.js

Next.js is a popular and developer-friendly React framework that makes implementing SSR a breeze.

The key capabilities Next.js brings to the table are:

1. File-based Routing – Pages are defined in files instead of React components. Next.js routes requests to the right page automatically.
2. Pre-rendering – HTML files are generated at build time enabling faster initial page loads.
3. Hybrid Rendering – Shifts gracefully between static generation and server side rendering automatically based on pages/content.
4. Rich Data Fetching Options – Integrated data fetching methods like getStaticProps and getServerSideProps help pre-populate pages with data easily.
5. Fullstack Capabilities – Node.js support allows easier server-side logic implementation.

Implementing SSR in Next.js is simple. Here is a sample page component:

export async function getServerSideProps() {

  // Fetch data from external API
  const res = await fetch(`https://...`)
  const data = await res.json()

  // Pass data to the page via props
  return { props: { data } }
}

export default function Home({ data }) {
  return (
    <div>
     <h1>My Data-Driven Server-Side Rendered Page</h1>
     {data.map((dataItem) => (
       <div key={dataItem.id}>
         <h2>{dataItem.name}</h2>
         <p>{dataItem.description}</p>
       </div>
     ))}
    </div>
  )
}

Here is what happens step-by-step when a user requests this page:

1. The getServerSideProps lifecycle method fetches data from an external API and returns it as page props. This fetch happens server-side.

2. Next.js pre-renders the page as static HTML, populating the markup using the fetched data.

3. The pre-rendered HTML is sent to the client for first load containing page data.

4. Hydration kicks in and the client-side JavaScript takes over for subsequent interactivity.

As you can see, adding SSR requires minimal additional effort compared to traditional React. Next.js handles all the heavy lifting for you.

Benefits of SSR with Next.js

Let’s recap the key benefits of using Next js SSR:

1. Faster First Load Times – Static HTML generation coupled with data pre-fetching achieves quicker first paint and time-to-interactive metrics.
2. Improved SEO – Full HTML content readily available for search engine crawlers to index. Easy to implement SEO best practices.
3. Hybrid Rendering – Get the best of both static generation and server side rendering based on use cases within the same app.
4. Scalability – Minimal Node.js server logic and static file serving allows cost-efficient scaling on CDNs and serverless platforms.
5. Easy Data Fetching – Simple data fetching via getServerSideProps and getStaticProps helps tackle the hardest problem in web dev – dealing with data.
6. Large Ecosystem – Benefit from the rich React ecosystem of tools, libraries and support available.
7. Future-Proof – Next.js receives frequent updates from Vercel, aligned closely with React roadmap items.

As you can see, Next.js ticks all boxes for a modern web tech stack optimized for performance, scale and developer productivity.

Conclusion

Server side rendering unlocks performance gains and SEO optimization needed by the most mission-critical React applications today. Next.js elegantly solves these problems by making SSR simple yet flexible.

Reach out to the experts

As an experienced software developer, I specialize in front-end development with React, Next.js and other modern web technologies.

I have over a decade of experience building performant, scalable and user-friendly web applications.

If you’re looking to build or revamp a React-based web app, get in touch to see how I can help. Whether you need an entire application built from scratch or a modernization of an existing one, I am available as a dedicated consultant to assist your team.