Catalog
concept#Architecture#Software Engineering#Performance

Server-Side Rendering (SSR)

An approach where HTML is rendered on the server and delivered fully to the client to improve initial load speed and SEO.

Server-side rendering (SSR) delivers fully rendered HTML from the server for each request, improving first-contentful paint and SEO for web applications.
Established
Medium

Classification

  • Medium
  • Technical
  • Architectural
  • Intermediate

Technical context

Content Delivery Network (CDN) for cached SSR responsesReverse proxy / edge servers for caching and routingServer frameworks (Next.js, Nuxt, Rails) for rendering pipelines

Principles & goals

Clear separation of server rendering and client hydrationPlan caching strategies early (CDN, edge cache)Minimize server render work per request
Build
Domain, Team

Use cases & scenarios

Compromises

  • Overload under high traffic without proper caches
  • Inconsistent rendering between client and server
  • Security risks from server-side template injections
  • Use edge or CDN caching for frequently requested pages
  • Perform hydration progressively to improve time-to-interactive
  • Reduce server load with rendering queues or pre-rendering

I/O & resources

  • URL routing, templates or components for server rendering
  • Server-side data sources / APIs for initial content
  • Caching strategy (CDN, edge, server cache)
  • Fully rendered HTML per request
  • Metadata for SEO and social previews
  • Client-hydratable state data

Description

Server-side rendering (SSR) delivers fully rendered HTML from the server for each request, improving first-contentful paint and SEO for web applications. It reduces initial client work but increases server load and complexity. SSR is commonly applied to content-driven sites and single-page applications that need fast initial renders and search-engine visibility.

  • Improved SEO and search engine indexing
  • Faster time-to-first-render for end users
  • Better social preview support for crawlers

  • Increased server load and scaling requirements
  • More complex infrastructure and deployments
  • Potential latency due to server-side data fetches

  • Time to First Byte (TTFB)

    Time until the first byte arrives from the server; impacts SSR latency.

  • First Contentful Paint (FCP)

    Time until first visible content; important for user perception with SSR.

  • Server requests per second

    Number of rendered page requests per second; relevant for capacity planning.

Next.js standard SSR

Next.js provides built-in SSR capabilities for React apps and server-side data fetching.

Ruby on Rails rendering

Classic server-side templates in Rails deliver HTML directly from the server without client hydration.

E-commerce shop with SSR and CDN

Product pages are server-rendered and cached via a CDN to achieve global performance.

1

Analyze requirements: SEO, performance, personalization

2

Select a framework/stack with SSR support

3

Introduce caching, CDN and monitoring before rollout

⚠️ Technical debt & bottlenecks

  • Spaghetti code in server-side templates
  • Outdated rendering strategies without incremental migration
  • Insufficient observability for server render paths
server-cpudatabase-latencycache-invalidation
  • Introducing SSR for internal admin tools without SEO need
  • Running persistent render jobs without rate limiting under high traffic
  • Embedding complex hydration logic in templates instead of modular JS
  • Ignoring cache invalidation leads to stale content
  • Underestimating rendering costs during traffic spikes
  • Lack of tests for SSR and CSR paths causes rendering errors
Server-side web development (Node.js, Ruby, etc.)Performance optimization and caching conceptsMonitoring, load testing and scaling strategies
SEO requirements and crawler compatibilityPerformance: time-to-first-byte and first-contentful-paintScalability and cost of rendering infrastructure
  • Requirement for stable network connectivity to rendering cluster
  • Limited server capacity under burst traffic
  • Compatibility with existing client frameworks