public function sealRequest(
        RequestInterface $request,
        SealingPublicKey $publicKey
    ): RequestInterface {
        $sealed = Simple::seal(
            (string) $request->getBody(),
            $publicKey
        );
        return $request->withBody(
            $this->adapter->stringToStream(
                Base64UrlSafe::encode($sealed)
            )
        );
    }