The Next.js Horror Picture Show: Why Your Website Is Slower Than You Think

This talk is confirmed. The time of the talk will be announced soon.
The recording will be published after editing. Multipass and Full ticket holders have early access.
Bookmark
Rate this content
Sentry
Promoted
Code breaks, fix it faster

Crashes, slowdowns, regressions in prod. Seer by Sentry unifies traces, replays, errors, profiles to find root causes fast.

Get started

In this data-driven talk, we will bypass marketing hype and unmask the hidden creatures behind Next.js., Using massive, real-world datasets from the HTTP Archive and the Chrome User Experience Report (CrUX), we will review the chronological evolution of Next.js performance and contrast its promised performance features with the real-world metrics of massive sites struggling with performance debt. Don’t dream your web is fast. Face the reality before it's too late.

This talk has been presented at React Advanced 2026, check out the latest edition of this React Conference.

Estela Franco
Estela Franco
Video transcription, chapters and summary will be available later.

Check out more articles and videos

We constantly think of articles and videos that might spark Git people interest / skill us up or help building a stellar career

A Guide to React Rendering Behavior
React Advanced 2022React Advanced 2022
25 min
A Guide to React Rendering Behavior
Top Content
This transcription provides a brief guide to React rendering behavior. It explains the process of rendering, comparing new and old elements, and the importance of pure rendering without side effects. It also covers topics such as batching and double rendering, optimizing rendering and using context and Redux in React. Overall, it offers valuable insights for developers looking to understand and optimize React rendering.
Speeding Up Your React App With Less JavaScript
React Summit 2023React Summit 2023
32 min
Speeding Up Your React App With Less JavaScript
Top Content
Mishko, the creator of Angular and AngularJS, discusses the challenges of website performance and JavaScript hydration. He explains the differences between client-side and server-side rendering and introduces Quik as a solution for efficient component hydration. Mishko demonstrates examples of state management and intercommunication using Quik. He highlights the performance benefits of using Quik with React and emphasizes the importance of reducing JavaScript size for better performance. Finally, he mentions the use of QUIC in both MPA and SPA applications for improved startup performance.
Routing in React 18 and Beyond
React Summit 2022React Summit 2022
20 min
Routing in React 18 and Beyond
Top Content
Routing in React 18 brings a native app-like user experience and allows applications to transition between different environments. React Router and Next.js have different approaches to routing, with React Router using component-based routing and Next.js using file system-based routing. React server components provide the primitives to address the disadvantages of multipage applications while maintaining the same user experience. Improving navigation and routing in React involves including loading UI, pre-rendering parts of the screen, and using server components for more performant experiences. Next.js and Remix are moving towards a converging solution by combining component-based routing with file system routing.
React Concurrency, Explained
React Summit 2023React Summit 2023
23 min
React Concurrency, Explained
Top Content
React 18's concurrent rendering, specifically the useTransition hook, optimizes app performance by allowing non-urgent updates to be processed without freezing the UI. However, there are drawbacks such as longer processing time for non-urgent updates and increased CPU usage. The useTransition hook works similarly to throttling or bouncing, making it useful for addressing performance issues caused by multiple small components. Libraries like React Query may require the use of alternative APIs to handle urgent and non-urgent updates effectively.
Optimizing HTML5 Games: 10 Years of Learnings
JS GameDev Summit 2022JS GameDev Summit 2022
33 min
Optimizing HTML5 Games: 10 Years of Learnings
Top Content
PlayCanvas is an open-source game engine used by game developers worldwide. Optimization is crucial for HTML5 games, focusing on load times and frame rate. Texture and mesh optimization can significantly reduce download sizes. GLTF and GLB formats offer smaller file sizes and faster parsing times. Compressing game resources and using efficient file formats can improve load times. Framerate optimization and resolution scaling are important for better performance. Managing draw calls and using batching techniques can optimize performance. Browser DevTools, such as Chrome and Firefox, are useful for debugging and profiling. Detecting device performance and optimizing based on specific devices can improve game performance. Apple is making progress with WebGPU implementation. HTML5 games can be shipped to the App Store using Cordova.
How React Compiler Performs on Real Code
React Advanced 2024React Advanced 2024
31 min
How React Compiler Performs on Real Code
Top Content
I'm Nadia, a developer experienced in performance, re-renders, and React. The React team released the React compiler, which eliminates the need for memoization. The compiler optimizes code by automatically memoizing components, props, and hook dependencies. It shows promise in managing changing references and improving performance. Real app testing and synthetic examples have been used to evaluate its effectiveness. The impact on initial load performance is minimal, but further investigation is needed for interactions performance. The React query library simplifies data fetching and caching. The compiler has limitations and may not catch every re-render, especially with external libraries. Enabling the compiler can improve performance but manual memorization is still necessary for optimal results. There are risks of overreliance and messy code, but the compiler can be used file by file or folder by folder with thorough testing. Practice makes incredible cats. Thank you, Nadia!

Workshops on related topic

React Performance Debugging Masterclass
React Summit 2023React Summit 2023
170 min
React Performance Debugging Masterclass
Top Content
Featured Workshop
Ivan Akulov
Ivan Akulov
Ivan’s first attempts at performance debugging were chaotic. He would see a slow interaction, try a random optimization, see that it didn't help, and keep trying other optimizations until he found the right one (or gave up).
Back then, Ivan didn’t know how to use performance devtools well. He would do a recording in Chrome DevTools or React Profiler, poke around it, try clicking random things, and then close it in frustration a few minutes later. Now, Ivan knows exactly where and what to look for. And in this workshop, Ivan will teach you that too.
Here’s how this is going to work. We’ll take a slow app → debug it (using tools like Chrome DevTools, React Profiler, and why-did-you-render) → pinpoint the bottleneck → and then repeat, several times more. We won’t talk about the solutions (in 90% of the cases, it’s just the ol’ regular useMemo() or memo()). But we’ll talk about everything that comes before – and learn how to analyze any React performance problem, step by step.
(Note: This workshop is best suited for engineers who are already familiar with how useMemo() and memo() work – but want to get better at using the performance tools around React. Also, we’ll be covering interaction performance, not load speed, so you won’t hear a word about Lighthouse 🤐)
AI for React Developers
React Advanced 2024React Advanced 2024
142 min
AI for React Developers
Top Content
Featured Workshop
Eve Porcello
Eve Porcello
Knowledge of AI tooling is critical for future-proofing the careers of React developers, and the Vercel suite of AI tools is an approachable on-ramp. In this course, we’ll take a closer look at the Vercel AI SDK and how this can help React developers build streaming interfaces with JavaScript and Next.js. We’ll also incorporate additional 3rd party APIs to build and deploy a music visualization app.
Topics:- Creating a React Project with Next.js- Choosing a LLM- Customizing Streaming Interfaces- Building Routes- Creating and Generating Components - Using Hooks (useChat, useCompletion, useActions, etc)
Tracing: Frontend Issues With Backend Solutions
React Summit US 2024React Summit US 2024
112 min
Tracing: Frontend Issues With Backend Solutions
Top Content
Featured WorkshopFree
Lazar Nikolov
Sarah Guthals
2 authors
Frontend issues that affect your users are often triggered by backend problems. In this workshop, you’ll learn how to identify issues causing slow web pages and poor Core Web Vitals using tracing.
Then, try it for yourself by setting up Sentry in a ready-made Next.js project to discover performance issues including slow database queries in an interactive pair-programming session.
You’ll leave the workshop being able to:- Find backend issues that might be slowing down your frontend apps- Setup tracing with Sentry in a Next.js project- Debug and fix poor performance issues using tracing
This will be a live 2-hour event where you’ll have the opportunity to code along with us and ask us questions.
From Frontend to Fullstack Development With Next.js
React Summit 2025React Summit 2025
91 min
From Frontend to Fullstack Development With Next.js
Top Content
Featured Workshop
Eric Burel
Eric Burel
Join us as we journey from React frontend development to fullstack development with Next.js. During this workshop, we'll follow along the official Next.js Learn tutorial with Eric Burel, professional trainer and author of NextPatterns.dev. Together, we'll set up a Next.js website and explore its server-side features to build performant apps.
Build a Headless WordPress App with Next.js and WPGraphQL
React Summit 2022React Summit 2022
173 min
Build a Headless WordPress App with Next.js and WPGraphQL
Top Content
Workshop
Kellen Mace
Kellen Mace
In this workshop, you’ll learn how to build a Next.js app that uses Apollo Client to fetch data from a headless WordPress backend and use it to render the pages of your app. You’ll learn when you should consider a headless WordPress architecture, how to turn a WordPress backend into a GraphQL server, how to compose queries using the GraphiQL IDE, how to colocate GraphQL fragments with your components, and more.
Next.js 13: Data Fetching Strategies
React Day Berlin 2022React Day Berlin 2022
53 min
Next.js 13: Data Fetching Strategies
Top Content
Workshop
Alice De Mauro
Alice De Mauro
- Introduction- Prerequisites for the workshop- Fetching strategies: fundamentals- Fetching strategies – hands-on: fetch API, cache (static VS dynamic), revalidate, suspense (parallel data fetching)- Test your build and serve it on Vercel- Future: Server components VS Client components- Workshop easter egg (unrelated to the topic, calling out accessibility)- Wrapping up