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+# Electron Builder Action
+
+**GitHub Action for building and releasing Electron apps**
+
+This is a GitHub Action for automatically building and releasing your Electron app using GitHub's CI/CD capabilities. It uses [`electron-builder`](https://github.com/electron-userland/electron-builder) to package your app for macOS, Windows and Linux, and release it to a platform like GitHub Releases.
+
+GitHub Actions allows you to build your app on all three platforms without having access to a machine/VM with each of these operating systems.
+
+## Usage
+
+1. Install and configure `electron-builder` in your Electron app. You can read about this in [the project's docs](https://www.electron.build) or in [my blog post](https://samuelmeuli.com/blog/2019-04-07-packaging-and-publishing-an-electron-app).
+
+   **Important:** You no longer need an NPM script which runs `electron-builder`, this action will do that for you.
+
+2. If you are building for macOS, you'll want your code to be [signed](https://samuelmeuli.com/blog/2019-04-07-packaging-and-publishing-an-electron-app/#code-signing). GitHub Actions therefore needs access to your code signing certificate:
+
+   - Open the Keychain Access app or the Apple Developer Portal. Export all certificates related to your app into a _single_ file (e.g. `certs.p12`) and set a strong password
+   - Base64-encode your certificates using the following command: `base64 -i certs.p12 -o encoded.txt`
+   - In your project's GitHub repository, go to Settings → Secrets and add the following two variables:
+     - `mac_certs`: Your encoded certificates, i.e. the content of the `encoded.txt` file you created before
+     - `mac_certs_password`: The password you set when exporting the certificates
+
+3. Add a workflow file to your project (e.g. `.github/workflows/build.yml`):
+
+   ```yml
+   name: Build/release
+
+   # Only run the workflow when a new tag is found
+   on:
+     push:
+       tags:
+         - "*"
+
+   jobs:
+     release:
+       runs-on: ${{ matrix.os }}
+
+       # Platforms to build on/for
+       strategy:
+         matrix:
+           os: [macos-10.14, windows-2019, ubuntu-18.04]
+
+       steps:
+         - name: Check out Git repository
+           uses: actions/checkout@v1
+
+         - name: Install Node.js and Yarn
+           uses: actions/setup-node@v1
+           with:
+             node-version: 10
+
+         - name: Build/release Electron app
+           uses: samuelmeuli/action-electron-builder@master
+           with:
+             github_token: ${{ secrets.github_token }} # Automatically generated
+             mac_certs: ${{ secrets.mac_certs }}
+             mac_certs_password: ${{ secrets.mac_certs_password }}
+   ```
+
+**Please note:** Before `v1.0`, the action's behavior might still change. Instead of using the latest commit (`samuelmeuli/action-electron-builder@master`), you might therefore want to pin a specific commit for now (e.g. `samuelmeuli/action-electron-builder@4fef1fe`).
+
+## Behavior
+
+The action…
+
+1. Installs your dependencies
+2. Runs your `build` NPM script (necessary if you use preprocessors, module bundlers, etc. for your app)
+3. Builds your app using `electron-builder`
+4. Optionally releases your app
+
+## Development
+
+### Contributing
+
+Suggestions and contributions are always welcome! Please discuss larger changes via issue before submitting a pull request.
+
+### TODO
+
+This project is still WIP. The following needs to be implemented before `v1.0`:
+
+- [ ] Add support for NPM (besides Yarn)
+- [ ] Make the `build` NPM script optional
+- [ ] In the sample workflow, add tag detection, which should decide whether to release after the build
+- [ ] Add support for publishing to Snapcraft