}
  }

  /** Builds a configured certificate pinner. */
  class Builder {
    val pins = mutableListOf<Pin>()

    /**
     * Pins certificates for `pattern`.
     *
     * @param pattern lower-case host name or wildcard pattern such as `*.example.com`.
     * @param pins SHA-256 or SHA-1 hashes. Each pin is a hash of a certificate's Subject Public Key
     *     Info, base64-encoded and prefixed with either `sha256/` or `sha1/`.