Build Basics

A build system is one of the most important parts of an engineering organization because each developer interacts with it potentially dozens or hundreds of times per day. A fully featured build system is necessary to enable developer productivity as an organization scales. For individual developers, it’s straightforward to just compile your code and so a build system might seem excessive. But at a larger scale, having a build system helps with managing shared dependencies, such as relying on another part of the code base, or an external resource, such as a library. Build systems help to make sure that you have everything you need to build your code before it starts building. Build systems also increase velocity when they’re set up to help engineers share resources and results.

This section covers some history and basics of building and build systems, including design decisions that went into making Bazel. If you’re familiar with artifact-based build systems, such as Bazel, Buck, and Pants, you can skip this section, but it’s a helpful overview to understand why artifact-based build systems are excellent at enabling scale.

Note: Much of this section’s content comes from the Build Systems and Build Philosophy chapter of the Software Engineering at Google book. Thank you to the original author, Erik Kuefler, for allowing its reuse and modification here!

• Why a Build System?

  If you haven’t used a build system before, start here. This page covers why you should use a build system, and why compilers and build scripts aren’t the best choice once your organization starts to scale beyond a few developers.

• Task-Based Build Systems

  This page discusses task-based build systems (such as Make, Maven, and Gradle) and some of their challenges.

• Artifact-Based Build Systems

  This page discusses artifact-based build systems in response to the pain points of task-based build systems.

• Distributed Builds

  This page covers distributed builds, or builds that are executed outside of your local machine. This requires more robust infrastructure to share resources and build results (and is where the true wizardry happens!)

• Dependency Management

  This page covers some complications of dependencies at a large scale and strategies to counteract those complications.