Package dashboard contains shared configuration and logic used by various pieces of the Go continuous build system.
When adding or removing builders, or changing a builder‘s build policy (which repos/branches get tested), you need to deploy the x/build/cmd/coordinator binary. Additionally, you usually want to re-deploy the x/build/app/appengine code to update https://build.golang.org/. The latter is only for humans (forcing columns to show up and adding the little black dots on cells that aren’t built), but doesn't affect what gets built.