if err != nil {
			log.Fatal(err)
		}
		if strings.HasSuffix(path, ".zip") {
			log.Fatalf("unexpected file during walk: %s", path)
		}
		name := filepath.ToSlash(path)
		w, err := zw.CreateRaw(&zip.FileHeader{
			Name:               name,
			Method:             zip.Store,
			CompressedSize64:   uint64(len(data)),
			UncompressedSize64: uint64(len(data)),
			CRC32:              crc32.ChecksumIEEE(data),
		})