host_context_ = num_threads ? CreateMultiThreadedHostContext(num_threads)
                              : CreateSingleThreadedHostContext();
  tfrt::RegisterStaticKernels(host_context_->GetMutableRegistry());

  // Build an ExecutionContext from the HostContext.
  auto builder = RequestContextBuilder(host_context_.get(), &resource_context_);

  // Get tensorflow::EagerContext for the kernel fallback.