gRPC does not support a PHP server implementation. However, implementing a gRPC server in PHP is possible using RoadRunner

• https://docs.roadrunner.dev/docs/plugins/grpc

I've experimented with this web server and gRPC server implementation, and it's incredible. We are using it to run a proxy server for Bigtable conformance tests (see googleapis/google-cloud-php#7959).

We should update the docs to highlight roadrunner.dev as a good option for PHP devs looking to implement a gRPC server. We can update the docs here: https://grpc.io/docs/languages/php/quickstart and potentially elsewhere.