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Download eBook or PDFRead online JavaScript Patterns Patterns focused on plain Javascript and Node.js Introduction to Design Patterns Introduction Introduction to Design Patterns Share a single global instance throughout our application Singleton Pattern Share a single global instance throughout our application Intercept and control interactions to target objects Proxy Pattern Intercept and control interactions to target objects Share properties among many objects of the same type Prototype Pattern Share properties among many objects of the same type Use observables to notify subscribers when an event occurs Observer Pattern Use observables to notify subscribers when an event occurs Split up your code into smaller, reusable pieces Module Pattern Split up your code into smaller, reusable pieces Add functionality to objects or classes without inheritance Mixin Pattern Add functionality to objects or classes without inheritance Use a central mediator object to handle communication between components Mediator/Middleware Pattern Use a central mediator object to handle communication between components Reuse existing instances when working with identical objects Flyweight Pattern Reuse existing instances when working with identical objects Use a factory function in order to create objects Factory Pattern Use a factory function in order to create objects An introduction to animating page transitions using the View Transitions API and libraries Animating View Transitions An introduction to animating page transitions using the View Transitions API and libraries Learn how to optimize your loading sequence to improve how quickly your app is usable Optimize your loading sequence Learn how to optimize your loading sequence to improve how quickly your app is usable Import code that has been exported by another module Static Import Import code that has been exported by another module Import parts of your code on demand Dynamic Import Import parts of your code on demand Load non-critical components when they are visible in the viewport Import On Visibility Load non-critical components when they are visible in the viewport Load non-critical resources when a user interacts with UI requiring it Import On Interaction Load non-critical resources when a user interacts with UI requiring it Dynamically load components based on the current route Route Based Splitting Dynamically load components based on the current route Split your code into small, reusable pieces Bundle Splitting Split your code into small, reusable pieces Optimize initial load through precaching, lazy loading, and minimizing roundtrips PRPL Pattern Optimize initial load through precaching, lazy loading, and minimizing roundtrips Reduce the bundle size by eliminating dead code Tree Shaking Reduce the bundle size by eliminating dead code Inform the browser of critical resources before they are discovered Preload Inform the browser of critical resources before they are discovered Fetch and cache resources that may be requested some time soon Prefetch Fetch and cache resources that may be requested some time soon Reduce the performance impact third-party scripts have on your site. Optimize loading third-parties Reduce the performance impact third-party scripts have on your site. Optimize list performance with list virtualization List Virtualization Optimize list performance with list virtualization Reduce the time needed to transfer scripts over the network. Compressing JavaScript Reduce the time needed to transfer scripts over the network. React Patterns Patterns focused on React and Next.js A UI library for building reusable user interface components Overview of React.js A UI library for building reusable user interface components Vercel's full-stack React framework for hybrid applications Overview of Next.js Vercel's full-stack React framework for hybrid applications Enforce separation of concerns by separating the view from the application logic Container/Presentational Pattern Enforce separation of concerns by separating the view from the application logic Pass reusable logic down as props to components throughout your application HOC Pattern Pass reusable logic down as props to components throughout your application Pass JSX elements to components through props Render Props Pattern Pass JSX elements to components through props Use functions to reuse stateful logic among multiple components throughout the app Hooks Pattern Use functions to reuse stateful logic among multiple components throughout the app Create multiple components that work together to perform a single task Compound Pattern Create multiple components that work together to perform a single task Render your application's UI on the client Client-side Rendering Render your application's UI on the client Generate HTML to be rendered on the server in response to a user request Server-side Rendering Generate HTML to be rendered on the server in response to a user request Deliver pre-rendered HTML content that was generated when the site was built Static Rendering Deliver pre-rendered HTML content that was generated when the site was built Update static content after you have built your site Incremental Static Generation Update static content after you have built your site Delay loading JavaScript for less important parts of the page Progressive Hydration Delay loading JavaScript for less important parts of the page Generate HTML to be rendered on the server in response to a user request Streaming Server-Side Rendering Generate HTML to be rendered on the server in response to a user request Server Components compliment SSR, rendering to an intermediate abstraction without needing to add to the JavaScript bundle React Server Components Server Components compliment SSR, rendering to an intermediate abstraction without needing to add to the JavaScript bundle With Next.js, there are several components that can help improve Core Web Vitals metrics Optimize Next.js apps for the Core Web Vitals With Next.js, there are several components that can help improve Core Web Vitals metrics A comprehensive guide to building React apps in 2025/2026, covering frameworks, build tools, routing, state management, and AI integration React Stack Patterns A comprehensive guide to building React apps in 2025/2026, covering frameworks, build tools, routing, state management, and AI integration Vue Patterns Patterns focused on Vue.js Introduction to Vue Patterns Introduction Introduction to Vue Patterns Self-contained modules that couple markup (HTML), logic (JS), and styles (CSS) within them Components Self-contained modules that couple markup (HTML), logic (JS), and styles (CSS) within them Optimize web app performance by asynchronously loading components. Async Components Optimize web app performance by asynchronously loading components. Functions to encapsulate and reuse stateful logic among multiple components Composables Functions to encapsulate and reuse stateful logic among multiple components Enforce separation of concerns by separating the view from the application logic Container/Presentational Pattern Enforce separation of concerns by separating the view from the application logic Utilize renderless components for managing and providing data Data Provider Pattern Utilize renderless components for managing and providing data Dynamically switch between components with the special element Dynamic Components Dynamically switch between components with the special element Have nested components access data without using props Provide/Inject Have nested components access data without using props Create component templates with programmatic JavaScript Render functions Create component templates with programmatic JavaScript Components that don't render their own markup Renderless components Components that don't render their own markup Compile-time syntactic sugar for using the Composition API