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Follow the directions on "Getting and building CockroachDB from source" or "Building from source on macOS" to get your development environment set up. If you’ve installed everything you need for the make build, you should already have more than enough for the Bazel build – for example, you don’t actually need Golang installed to build with Bazel (the Bazel build will download Go toolchain bits as needed).
Note that you do need a full installation of XCode to build on macOS. (No, a command-line tools instance does not suffice.)
Getting started
Introduction to dev
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