diff --git a/sdks/go/pkg/beam/runners/prism/internal/jobservices/management.go b/sdks/go/pkg/beam/runners/prism/internal/jobservices/management.go
index 3526ee00cc1f..5760ce7871b7 100644
--- a/sdks/go/pkg/beam/runners/prism/internal/jobservices/management.go
+++ b/sdks/go/pkg/beam/runners/prism/internal/jobservices/management.go
@@ -127,6 +127,9 @@ func (s *Server) Prepare(ctx context.Context, req *jobpb.PrepareJobRequest) (*jo
 			urns.TransformCombinePerKey,
 			urns.TransformCombineGlobally,      // Used by Java SDK
 			urns.TransformCombineGroupedValues, // Used by Java SDK
+			urns.TransformMerge,                // Used directly by Python SDK if "pre-optimized"
+			urns.TransformPreCombine,           // Used directly by Python SDK if "pre-optimized"
+			urns.TransformExtract,              // Used directly by Python SDK if "pre-optimized"
 			urns.TransformAssignWindows:
 		// Very few expected transforms types for submitted pipelines.
 		// Most URNs are for the runner to communicate back to the SDK for execution.
@@ -165,12 +168,6 @@ func (s *Server) Prepare(ctx context.Context, req *jobpb.PrepareJobRequest) (*jo
 
 			check("OnWindowExpirationTimerFamily", pardo.GetOnWindowExpirationTimerFamilySpec(), "") // Unsupported for now.
 
-		case "":
-			// Composites can often have no spec
-			if len(t.GetSubtransforms()) > 0 {
-				continue
-			}
-			fallthrough
 		case urns.TransformTestStream:
 			var testStream pipepb.TestStreamPayload
 			if err := proto.Unmarshal(t.GetSpec().GetPayload(), &testStream); err != nil {
@@ -179,7 +176,15 @@ func (s *Server) Prepare(ctx context.Context, req *jobpb.PrepareJobRequest) (*jo
 
 			t.EnvironmentId = "" // Unset the environment, to ensure it's handled prism side.
 			testStreamIds = append(testStreamIds, tid)
+
 		default:
+			// Composites can often have some unknown urn, permit those.
+			// Eg. The Python SDK has urns "beam:transform:generic_composite:v1", "beam:transform:pickled_python:v1", as well as the deprecated "beam:transform:read:v1",
+			// but they are composites. Since we don't do anything special with the high level, we simply use their internal subgraph.
+			if len(t.GetSubtransforms()) > 0 {
+				continue
+			}
+			// But if not, fail.
 			check("PTransform.Spec.Urn", urn+" "+t.GetUniqueName(), "<doesn't exist>")
 		}
 	}
@@ -191,7 +196,8 @@ func (s *Server) Prepare(ctx context.Context, req *jobpb.PrepareJobRequest) (*jo
 	// Inspect Windowing strategies for unsupported features.
 	for wsID, ws := range job.Pipeline.GetComponents().GetWindowingStrategies() {
 		check("WindowingStrategy.AllowedLateness", ws.GetAllowedLateness(), int64(0))
-		check("WindowingStrategy.ClosingBehaviour", ws.GetClosingBehavior(), pipepb.ClosingBehavior_EMIT_IF_NONEMPTY)
+		// Both Closing behaviors are identical without additional trigger firings.
+		check("WindowingStrategy.ClosingBehaviour", ws.GetClosingBehavior(), pipepb.ClosingBehavior_EMIT_IF_NONEMPTY, pipepb.ClosingBehavior_EMIT_ALWAYS)
 		check("WindowingStrategy.AccumulationMode", ws.GetAccumulationMode(), pipepb.AccumulationMode_DISCARDING)
 		if ws.GetWindowFn().GetUrn() != urns.WindowFnSession {
 			check("WindowingStrategy.MergeStatus", ws.GetMergeStatus(), pipepb.MergeStatus_NON_MERGING)
@@ -398,3 +404,50 @@ func (s *Server) GetState(_ context.Context, req *jobpb.GetJobStateRequest) (*jo
 		Timestamp: timestamppb.New(j.stateTime),
 	}, nil
 }
+
+// DescribePipelineOptions is a no-op since it's unclear how it is to function.
+// Apparently only implemented in the Python SDK.
+func (s *Server) DescribePipelineOptions(context.Context, *jobpb.DescribePipelineOptionsRequest) (*jobpb.DescribePipelineOptionsResponse, error) {
+	return &jobpb.DescribePipelineOptionsResponse{
+		Options: []*jobpb.PipelineOptionDescriptor{},
+	}, nil
+}
+
+// GetStateStream returns the job state as it changes.
+func (s *Server) GetStateStream(req *jobpb.GetJobStateRequest, stream jobpb.JobService_GetStateStreamServer) error {
+	s.mu.Lock()
+	job, ok := s.jobs[req.GetJobId()]
+	s.mu.Unlock()
+	if !ok {
+		return fmt.Errorf("job with id %v not found", req.GetJobId())
+	}
+
+	job.streamCond.L.Lock()
+	defer job.streamCond.L.Unlock()
+
+	state := job.state.Load().(jobpb.JobState_Enum)
+	for {
+		job.streamCond.L.Unlock()
+		stream.Send(&jobpb.JobStateEvent{
+			State:     state,
+			Timestamp: timestamppb.Now(),
+		})
+		job.streamCond.L.Lock()
+		switch state {
+		case jobpb.JobState_CANCELLED, jobpb.JobState_DONE, jobpb.JobState_DRAINED, jobpb.JobState_UPDATED, jobpb.JobState_FAILED:
+			// Reached terminal state.
+			return nil
+		}
+		newState := job.state.Load().(jobpb.JobState_Enum)
+		for state == newState {
+			select { // Quit out if the external connection is done.
+			case <-stream.Context().Done():
+				return context.Cause(stream.Context())
+			default:
+			}
+			job.streamCond.Wait()
+			newState = job.state.Load().(jobpb.JobState_Enum)
+		}
+		state = newState
+	}
+}