[{"slug":"what-is-sapper","title":"What is Sapper?","body":"\n

First, you have to know what Svelte is. Svelte is a UI framework with a bold new idea: rather than providing a library that you write code with (like React or Vue, for example), it's a compiler that turns your components into highly optimized vanilla JavaScript. If you haven't already read the introductory blog post, you should!

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Sapper is a Next.js-style framework (more on that here) built around Svelte. It makes it embarrassingly easy to create extremely high performance web apps. Out of the box, you get:

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Code-splitting, dynamic imports and hot module replacement, powered by webpack
Server-side rendering (SSR) with client-side hydration
Service worker for offline support, and all the PWA bells and whistles
The nicest development experience you've ever had, or your money back

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It's implemented as Express middleware. Everything is set up and waiting for you to get started, but you keep complete control over the server, service worker, webpack config and everything else, so it's as flexible as you need it to be.

\n "},{"slug":"how-to-use-sapper","title":"How to use Sapper","body":"\n

Step one

Create a new project, using degit:

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npx degit \"sveltejs/sapper-template#rollup\" my-app\n      cd my-app\n      npm install # or yarn!\n      npm run dev\n

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Step two

Go to localhost:3000. Open my-app in your editor. Edit the files in the src/routes directory or add new ones.

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Step three

...

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Step four

Resist overdone joke formats.

\n "},{"slug":"why-the-name","title":"Why the name?","body":"\n

In war, the soldiers who build bridges, repair roads, clear minefields and conduct demolitions — all under combat conditions — are known as sappers.

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For web developers, the stakes are generally lower than those for combat engineers. But we face our own hostile environment: underpowered devices, poor network connections, and the complexity inherent in front-end engineering. Sapper, which is short for Svelte app maker, is your courageous and dutiful ally.

\n "},{"slug":"how-is-sapper-different-from-next","title":"How is Sapper different from Next.js?","body":"\n

Next.js is a React framework from Vercel, and is the inspiration for Sapper. There are a few notable differences, however:

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It's powered by Svelte instead of React, so it's faster and your apps are smaller
Instead of route masking, we encode route parameters in filenames. For example, the page you're looking at right now is src/routes/blog/[slug].svelte
As well as pages (Svelte components, which render on server or client), you can create server routes in your routes directory. These are just .js files that export functions corresponding to HTTP methods, and receive Express request and response objects as arguments. This makes it very easy to, for example, add a JSON API such as the one powering this very page
Links are just <a> elements, rather than framework-specific <Link> components. That means, for example, that this link right here, despite being inside a blob of HTML, works with the router as you'd expect.

\n "},{"slug":"how-can-i-get-involved","title":"How can I get involved?","body":"\n

We're so glad you asked! Come on over to the Svelte and Sapper repos, and join us in the Discord chatroom. Everyone is welcome, especially you!

\n "}]

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