code: func genBinaries(osType string) {
  	cwd := filepath.Join(workDir, osType)
  	check(os.MkdirAll(cwd, 0755))
  	image := goDockerImage
  	args := []string{
  		"run",
  		"--rm",
  		"--volume=" + cwd + ":/OUT",
  		"--volume=" + filepath.Join(releaseDir, "build-binaries.go") + ":" + genBinariesProgram + ":ro",
  	}
  	if isWIP() {
  		args = append(args, "--volume="+localCamliSource()+":/IN:ro",
  			image, goCmd, "run", genBinariesProgram, "--rev=WIP:/IN", "--os="+osType)
  	} else {
  		args = append(args, image, goCmd, "run", genBinariesProgram, "--rev="+rev(), "--os="+osType)
  	}
  	cmd := exec.Command("docker", args...)
  	cmd.Stdout = os.Stdout
  	cmd.Stderr = os.Stderr
  	if err := cmd.Run(); err != nil {
  		log.Fatalf("Error building binaries in go container: %v", err)
  	}
  	fmt.Printf("Perkeep binaries successfully generated in %v\n", filepath.Join(cwd, "bin"))
  }
docs: // genBinaries runs go run make.go for the given osType in a docker container.