     end
   end
 
-  defp create_build_info(path, build_number, sha, version_string) do
+  defp create_build_info(path, build_number, sha) do
+    short_sha = String.slice(sha, 0..6)
+    version_string =  "#{today}-#{build_number}-#{short_sha}"
+
     build_info_template = ~s"""
     ---
     version: #{version_string}

    end
  end

  defp archive(path, version_string) do
    if File.exists?(Path.join([path, 'bin', 'archive'])) do
      IO.puts("running archive")
      output = Porcelain.shell("cd #{path} && ./bin/archive")

      end
      output.status
    else
      write_archive(path, version_string)
    end
  end

  defp write_archive(path, version_string) do
    archive_path = Path.join(System.tmp_dir(), "#{version_string}.tgz")
    System.cmd("tar", ["--dereference", "-czf", archive_path, path])
    System.cmd("mv", [archive_path, path])
    IO.puts("created #{version_string}.tgz")
    {:ok, nil}
  end

  defp valid?(opts) do
