Buck vs fastlane: What are the differences?

Buck: A build system developed and used by Facebook. Buck encourages the creation of small, reusable modules consisting of code and resources, and supports a variety of languages on many platforms; fastlane: Connect all iOS deployment tools into one streamlined workflow. fastlane lets you define and run your deployment pipelines for different environments. It helps you unify your app’s release process and automate the whole process. fastlane connects all fastlane tools and third party tools, like CocoaPods.

Buck belongs to "Java Build Tools" category of the tech stack, while fastlane can be primarily classified under "Mobile Continuous Integration".

Some of the features offered by Buck are:

• Speed up your Android builds. Buck builds independent artifacts in parallel to take advantage of multiple cores. Further, it reduces incremental build times by keeping track of unchanged modules so that the minimal set of modules is rebuilt.
• Introduce ad-hoc build steps for building artifacts that are not supported out-of-the-box using the standard Ant build scripts for Android.
• Keep the logic for generating build rules in the build system instead of requiring a separate system to generate build files.

On the other hand, fastlane provides the following key features:

• Connect all build tools together
• Define multiple lanes for different needs
• Jenkins Integration

Buck and fastlane are both open source tools. It seems that fastlane with 26K GitHub stars and 3.97K forks on GitHub has more adoption than Buck with 6.82K GitHub stars and 1.02K GitHub forks.