Continuous Integration & Delivery
In the previous lesson, we talked about writing tests.
But tests are only useful if we run them regularly.
The most popular CI systems for Flutter are Codemagic and Github Actions. These systems let you automate your tests by setting up workflows that run when you want.
For example, you could use them to run your entire test suite when you push a new branch or open/update a pull request. This is useful as you can ensure that all the tests are green before merging changes to the main branch.
You can also use CI tools to build release versions of your apps and deliver them to the App Store or Play Store.
Or, if you want to distribute internal builds to your beta testers, you can do that too.
So, how are Codemagic and GitHub Actions different?
Codemagic
The main strength of Codemagic is that it’s easy to use. You can set up and customize your workflows visually and add custom build steps and various 3rd party integrations. For example, you can configure it to send a Slack notification when your builds succeed or fail.
This article offers a good overview of Codemagic:
Codemagic offers 500 build minutes for free every month. See this pricing page for more information.
GitHub Actions
Unlike Codemagic, GitHub Actions does not offer a UI interface. Instead, you write custom build workflows in yaml format, and you can use pre-built actions that are freely available in the GitHub marketplace.
For an example of how GitHub workflows look like, you can check the documentation for the Flutter action:
For a detailed introduction to GitHub Actions, you can follow this guide:
Or if you prefer a video tutorial, Robert Brunhage has you covered:
Actions are quite powerful, but they come with a steeper learning curve. If you make a typo or mistake in your workflow file, you can only find out what went wrong by inspecting the build log once the build has completed.
Regarding pricing, GitHub Actions offers 2000 minutes per month on the Free plan, though macOS minutes are 10x more expensive than the basic Linux minutes. For a full overview of GitHub Actions pricing, see this page:
Fastlane
Fastlane is an open-source tool that makes it easy to automate beta deployments and releases for your iOS and Android apps.
Fastlane is particularly useful for managing and updating the code signing certificates (which is a painful thing to do on iOS) and signing release apps.
As a result, many people use Fastlane in their Flutter build workflows, either with GitHub Actions or Codemagic.
The official Flutter documentation offers a good overview of continuous delivery with fastlane:
Rody Davis also has a useful guide for setting up Flutter & Fastlane in his blog:
It can take a bit of time to set up Fastlane the first time, but once it’s up and running, it can save a lot of time in the future.
Releasing to the App Stores
Once your app is ready, it’s time to release it to your users.
The official documentation includes some important steps that you need to follow in preparation for this:
Or, if you prefer, you can watch these video tutorials:
- Flutter Tutorial - How To Publish Flutter App on the Play Store
- Flutter Tutorial - How to Publish Flutter App on the App Store
If your app uses Firebase, you may also find this release checklist useful:
Daily Challenge - Add test CI workflow
Take one of your existing Flutter projects and add a basic CI workflow that runs the tests every time you push your changes to GitHub.
You can use this guide as a reference:
Happy coding!