# Code Signing

Code signing is a security technology that you use to certify that an app was 
created by you.

On macOS the system can detect any change to the  app, whether the change is
introduced accidentally or by malicious code.

On Windows the system assigns a trust level to your code signing certificate which
if you don't have, or if your trust level is low will cause security dialogs to
appear when users start using your application.  Trust level builds over time
so it's better to start code signing as early as possible.

While it is possible to distribute unsigned apps, it is not recommended. 
For example, here's what macOS users see when attempting to start an unsigned app:

![unsigned app warning on macOS](https://user-images.githubusercontent.com/2289/39488937-bdc854ba-4d38-11e8-88f8-7b3c125baefc.png)

> App can't be opened because it is from an unidentified developer

If you are building an Electron app that you intend to package and distribute, 
it should be code signed. The Mac and Windows app stores do not allow unsigned 
apps.

# Signing macOS builds

Before signing macOS builds, you must do the following:

1. Enroll in the [Apple Developer Program](Apple Developer Program) (requires an annual fee)
2. Download and install Xcode
3. Generate, download, and install [signing certificates]

There are a number of tools for signing your packaged app:

- [`electron-osx-sign`] is a standalone tool for signing macOS packages.
- [`electron-packager`] bundles `electron-osx-sign`. If you're using `electron-packager`,
pass the `--osx-sign=true` flag to sign your build.
  - [`electron-forge`] uses `electron-packager` internally, you can set the `osxSign` option
    in your forge config.
- [`electron-builder`] has built-in code-signing capabilities. See [electron.build/code-signing](https://www.electron.build/code-signing)

For more info, see the [Mac App Store Submission Guide].

# Signing Windows builds

Before signing Windows builds, you must do the following:

1. Get a Windows Authenticode code signing certificate
2. Install Visual Studio 2015/2017 (to get the signing utility)

You can get a code signing certificate from a lot of resellers, popular ones include:

* [digicert](https://www.digicert.com/code-signing/microsoft-authenticode.htm)
* [Comodo](https://www.comodo.com/landing/ssl-certificate/authenticode-signature/)
* [GoDaddy](https://au.godaddy.com/web-security/code-signing-certificate)
* Amongst others, please shop around to find one that suits your needs, Google is your friend :)

There are a number of tools for signing your packaged app:

- [`electron-winstaller`] will generate an installer for windows and sign it for you
- [`electron-forge`] can sign installers it generates through the Squirrel.Windows or MSI targets.
- [`electron-builder`] can sign some of its windows targets

## Windows Store

See the [Windows Store Guide].

[Apple Developer Program]: https://developer.apple.com/programs/
[`electron-builder`]: https://github.com/electron/electron-builder
[`electron-forge`]: https://github.com/electron-userland/electron-forge
[`electron-osx-sign`]: https://github.com/electron-userland/electron-osx-sign
[`electron-packager`]: https://github.com/electron-userland/electron-packager
[`electron-winstaller`]: https://github.com/electron/windows-installer
[Xcode]: https://developer.apple.com/xcode
[signing certificates]: https://github.com/electron-userland/electron-osx-sign/wiki/1.-Getting-Started#certificates
[Mac App Store Submission Guide]: mac-app-store-submission-guide.md
[Windows Store Guide]: windows-store-guide.md