What are the key upgrades introduced in Next.js 15?
Next.js 15 includes enhanced integration of Turbopack, support for React 19, stability improvements, and new features like the Next Form component and after hooks for request lifecycle management.
Why did Next.js 15 take longer to release compared to previous versions?
The team decided to take more time to ensure the release was polished, bundling significant changes and stability improvements to set a new baseline for the app router.
What is the significance of Turbopack in Next.js 15?
Turbopack is now stable for development, offering a 95% faster hot module replacement (HMR) compared to previous versions, significantly improving developer iteration speed.
How does Turbopack improve development performance?
Turbopack reduces the time it takes to see changes reflected in the browser by only recompiling the affected parts of the code, rather than the entire module graph, resulting in faster updates.
What is the motivation behind the async request APIs in Next.js 15?
The async request APIs were introduced to prepare for the upcoming dynamic IO feature, which simplifies the distinction between static and dynamic content by marking pages as dynamic if they use promises.
How does Next.js 15 handle static vs. dynamic content determination?
Next.js 15 uses dynamic IO to determine if a page is static or dynamic based on whether the code uses asynchronous operations, marking it as dynamic if it does.
What is the relationship between Next.js and React in terms of development?
Next.js and React have a close relationship, with Next.js often integrating React's latest features, such as server components and new directives, to enhance the framework's capabilities.
Why did Next.js 15 release with an RC version of React 19?
Next.js 15 released with React 19 RC to align with the React team's roadmap, but the stable release was delayed due to a significant change in React's suspense behavior, which Next.js decided not to block on.
What is the purpose of the Next Form component in Next.js 15?
The Next Form component is a drop-in replacement for the standard HTML form, adding features like prefetching and client-side navigation to improve form handling and user experience.
How does Next.js support self-hosting and non-Vercel deployments?
Next.js supports self-hosting through tools like Open Next, which allows deployment on various serverless platforms. The team is also working to standardize infrastructure outputs to make self-hosting easier.
- Enhanced TurboPack integration for faster development
- Support for React 19
- Improved stability and numerous bug fixes
- Next Form component for easier form handling
- After hooks for request lifecycle access
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