Server-Side Rendering vs. Static Site Generation in the Modern Web

Hello everyone, 🤗

Today, I’ll delve into Server-Side Rendering (SSR) and Static Site Generation (SSG) in Next.js. These concepts presented a significant learning curve for me, but through lots of hands-on experience and numerous side projects, I’ve finally grasped some of their core principles.

As web development progresses, choosing between SSR and SSG can be essential for building efficient and scalable applications. Frameworks like React and Next.js provide excellent support for both, each with its own strengths.

What is Server-Side Rendering (SSR)?

Server-Side Rendering generates HTML for a page on the server at runtime, based on the user’s request. This ensures that the user receives a fully rendered page upon loading, improving SEO and providing faster Time to First Byte (TTFB) compared to traditional client-side rendering.

Key Benefits:

• Dynamic Content: Ideal for pages that require frequently updated or personalized data.
• SEO Optimization: Search engines can crawl fully rendered pages easily.

Example in Next.js (app directory, v13 and later):

import { getTeamMembers } from '@/app/api/strapi';
import TeamMemberCard from '@/components/team-member-card';
import React from 'react'

const Team = async () => {
  const teamMembers = await getTeamMembers()

  return (
    <div>
      <h1 className='text-xl font-semibold mb-4'>Our Team</h1>
      <div className='grid grid-cols-1 md:grid-cols-2 lg:grid-cols-4 gap-8'>
        {teamMembers.data.map((member: TeamMemberProps) => (
          <TeamMemberCard key={member.documentId} {...member}/>
        ))}
      </div>
    </div>
  )
}

export default Team

In this example, teamMembers is fetched server-side using the new app directory features and passed to the component.

Downsides of SSR:

• Slower Initial Load Time: Each request to the server requires rendering the page on the fly, which can introduce latency, especially if the server is slow or under heavy load.
• Higher Server Load: Since the server generates the page on each request, it can become a bottleneck. High traffic can result in performance degradation or even downtime if the server can’t handle the load.
• Less Caching Efficiency: While caching strategies can help mitigate performance issues, SSR doesn’t benefit from the same level of optimization as SSG, where pages can be cached at the CDN level.
• State Management Challenges: Managing server-side state (especially when interacting with databases or APIs) can become more complex with SSR, and it may involve additional synchronization between the server and client.

What is Static Site Generation (SSG)?

Static Site Generation creates HTML at build time, producing static files that can be served by a Content Delivery Network (CDN). This approach is highly performant for pages where content does not change frequently.

Key Benefits:

• Speed: Pre-rendered pages ensure ultra-fast load times.
• Scalability: Static files can handle high traffic with minimal server resources.

Example in Next.js (app directory, v13 and later):

import { getTeamMembers } from '@/app/api/strapi';
import TeamMemberCard from '@/components/team-member-card';
import React from 'react'

const Team = async () => {
  const teamMembers = await getTeamMembers()

  return (
    <div>
      <h1 className='text-xl font-semibold mb-4'>Our Team</h1>
      <div className='grid grid-cols-1 md:grid-cols-2 lg:grid-cols-4 gap-8'>
        {teamMembers.data.map((member: TeamMemberProps) => (
          <TeamMemberCard key={member.documentId} {...member}/>
        ))}
      </div>
    </div>
  )
}

export default Team

Here’s a brief explanation:

• generateStaticParams: This function fetches the list of team members and returns an array of parameters (slugs) that will be used to generate static pages for each team member, while the component fetches the details of a team member based on the slug and renders the content. Since it uses generateStaticParams, it will be statically generated at build time.

This setup ensures that the pages for each team member are pre-rendered and served as static HTML, which is the essence of SSG.

Downsides of SSG:

• Longer Build Times: For large sites with a high number of pages, generating static pages can be time-consuming. This can lead to delays during deployment, especially if the content updates frequently.
• Limited to Non-Dynamic Content: SSG is best suited for content that doesn’t change often or requires real-time interaction. Dynamic content is challenging to integrate and may require additional workarounds like client-side JavaScript or hybrid approaches (e.g., ISR).
• Stale Content: Static pages are generated at build time, which means any content updates won’t reflect until the next build and deployment. This can be problematic if the website relies on real-time or frequently changing data.
• Difficult to Handle User-Specific Content: If your application requires personalized content (like user dashboards, authenticated areas, etc.), SSG is less ideal, since static pages aren’t tailored to individual users.
• Dependency on CDNs: SSG relies heavily on CDNs for delivering static content efficiently. If there’s an issue with the CDN, the site might experience downtime or slowdowns.
• Choosing Between SSR and SSG

Use SSR when:

• Content changes frequently and must be personalized.
• SEO is critical, and the data needs to be up-to-date.
• Example: E-commerce product pages with real-time inventory.

Use SSG when:

• Content is largely static or updated at predictable intervals.
• Scalability and performance are top priorities.
• Example: Marketing websites or blogs.

Hybrid Approaches

Next.js also supports hybrid rendering, allowing developers to combine SSR and SSG within the same application. For example, static generation can be used for blog pages, while server-side rendering is used for a user’s dashboard.

Conclusion

Understanding the strengths and limitations of SSR and SSG is essential for creating efficient web applications. By leveraging frameworks like Next.js, developers can choose the right approach — or even a hybrid one — to meet their application’s specific needs. This flexibility ensures both optimal performance and a seamless user experience.

Until next time 👋,

Stefania

P.S. Don’t forget to like, comment, and share with others if you found this helpful!

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