Flutter Bitbucket Pipeline cache

Flutter Bitbucket Pipeline cache

How to speed up the flutter Bitbucket build pipelines by caching libraries and build files.

Alexander Thiele · 2 minute read

It was pretty tricky to speed up the pipeline since there are not so many resources on how to cache your flutter app on Bitbucket Pipeline.

Read how to setup bitbucket pipelines for flutter if you just want to get started.

How Dart/Flutter saves dependencies

Whenever you run flutter pub get, the system downloads all dependencies to the folder .pub-cache in your home directory. The Folder contains all cached dependencies and will look similar to:


Caching those dependencies makes sense since a plugin with a specific version will never change. It's basically not possible to upload the same version with a different code to pub.dev.

Dependency version changes

Whenever you change your dependencies, the new versions will appear in the same Folder.

.pub-cache/hosted/pub.dartlang.org/linkfive_purchases-2.0.1/ .pub-cache/hosted/pub.dartlang.org/linkfive_purchases-2.0.2/

Alright. Let's cache the dependencies with bitbucket pipelines

bitbucket-pipelines.yml config definitions

We want all dependencies to be cached in the .pub-cache folder on bitbucket.

For this we define certain definitions that can be referenced in future steps.

definitions: steps: - step: &Flutter-pub-get name: Flutter Pub Get script: - flutter pub get artifacts: - .dart_tool/** - .flutter-plugins - .flutter-plugins-dependencies - build/** caches: - dartpubcache - step: &Lint-and-test name: Flutter lint and test caches: - dartpubcache script: - flutter analyze - flutter test ./test caches: dartpubcache: $HOME/.pub-cache

We define the steps Flutter-pub-get and Lint-and-test plus the cache directory $HOME/.pub-cache

Now we just need to use the steps in any pipeline runner.

pipelines: pull-requests: '**': - step: *Flutter-pub-get - step: *Lint-and-test - step: name: Build Flutter Android appbundle deployment: production caches: - dartpubcache script: - flutter build appbundle

and Bitbucket also notes that the cache was downloaded

Cache "dartpubcache": Downloading Cache "dartpubcache": Downloaded 40.6 MiB in 2 seconds Cache "dartpubcache": Extracting Cache "dartpubcache": Extracted in 1 seconds

Cache duration

The bitbucket cache will refreshed after a week. You can also delete the cache manually inside the bitbucket pipeline section. Click on the top right Cache button.

Flutter dependency update

It also does not cause any problems if you change your dependencies before the cache has expired. The only thing that happens is that the command flutter pub get takes a little longer because additional dependencies are downloaded.

Flutter bitbucket pipeline lint test cache

Flutter pipeline pull request

Best, Alex