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How to deploy a Sapper PWA on GitHub Pages

pixeline profile image Alexandre Plennevaux ・2 min read

Here is a quick and easy tutorial on how to deploy a PWA made with Sapper & Svelte on GitHub Pages.

  1. Configure your project's GitHub repository (in the repository /settings) to use the GitHub Pages functionality and choose to publish the content of the gh-pages branch.

GitHub Settings interface

Pay extra attention to your repository slug name: it will become the foldername value to use later. In this example, it is "mathr", a personal project of mine (math quizz game for my bored teenage girl πŸ€“ )

1. Build your SPA

... until the point of readiness (obviously ;-) )

2. Export the code and check if it is good to go

npx sapper export
npx serve __sapper__/export

4. Serving from a subfolder

That's the tricky part. Since as a GitHub Pages, your project will most probably be served in a subfolder (unless you use your own domain name), modify the file src/server.js, to mention your subfolder. It will be used as the base tag href attribute value:

<base href="/yourproject">
        'yourproject', // <-- replace yourproject with your repo name
        compression({ threshold: 0 }),
        sirv('static', { dev }),
    .listen(PORT, err => {
        if (err) console.log('error', err);

5. Deploy via the Terminal

We want to be able to deploy using a simple command:

npm run deploy

To achieve that, install this npm package: gh-pages - npm

npm install gh-pages --save-dev

Then, in the root of your project folder, create the file /scripts/gh-pages.js with this content:

var ghpages = require('gh-pages');

    '__sapper__/export/yourproject',// <-- replace yourproject with your repo name
        branch: 'gh-pages',
        repo: 'https://github.com/username/yourproject.git',
        user: {
            name: 'Your name',
            email: 'Your Email address'
    () => {
        console.log('Deploy Complete!')

Finally, update your package.json project file with the following (again, replace yourproject with your repo name):

"scripts": {
    "export": "sapper export --basepath yourproject --legacy",
    "deploy": "npm run export && node ./scripts/gh-pages.js"


6. Finally, test it out !

From inside your project folder, launch this command:

npm run deploy

Following these steps worked for me πŸš€. Do let me know if you run into hiccups ;-)


Editor guide
emma profile image
Emma Goto πŸ™

This was really useful - thanks!! Just want to point out that if you choose the webpack option when setting up Sapper, the --legacy export option doesn't work, so you'll need to make sure you use Rollup.

pixeline profile image
Alexandre Plennevaux Author

Hi Emma, Thank you for your feedback, I'm glad this was helpful :-)

shaone profile image

Very helpful, big thanks!

I'd had a few goes at this setup. Your article finally gave me the missing piece, with the explanation about the /subfolder, aha :)