diff --git a/python/langsmith/_internal/_operations.py b/python/langsmith/_internal/_operations.py
index 66decff0f..89d5f12fc 100644
--- a/python/langsmith/_internal/_operations.py
+++ b/python/langsmith/_internal/_operations.py
@@ -141,6 +141,27 @@ def serialize_run_dict(
         attachments=attachments if attachments is not None else None,
     )
 
+def serialize_run_dict_for_compressed_ingest(
+    operation: Literal["post", "patch"], payload: dict
+):
+    inputs = payload.pop("inputs", None)
+    outputs = payload.pop("outputs", None)
+    events = payload.pop("events", None)
+    attachments = payload.pop("attachments", None)
+    serialized = ...
+    extra = ...
+    return SerializedRunOperation(
+        operation=operation,
+        id=payload["id"],
+        trace_id=payload["trace_id"],
+        _none=_dumps_json(payload),
+        inputs=_dumps_json(inputs) if inputs is not None else None,
+        outputs=_dumps_json(outputs) if outputs is not None else None,
+        events=_dumps_json(events) if events is not None else None,
+        attachments=attachments if attachments is not None else None,
+    )
+
+
 
 def combine_serialized_queue_operations(
     ops: list[Union[SerializedRunOperation, SerializedFeedbackOperation]],
diff --git a/python/langsmith/client.py b/python/langsmith/client.py
index a6377e23e..63c93fc03 100644
--- a/python/langsmith/client.py
+++ b/python/langsmith/client.py
@@ -494,10 +494,13 @@ def __init__(
             if info is None or isinstance(info, ls_schemas.LangSmithInfo)
             else ls_schemas.LangSmithInfo(**info)
         )
+        self.compressed_multipart_buffer = ...
         weakref.finalize(self, close_session, self.session)
         atexit.register(close_session, session_)
         # Initialize auto batching
-        if auto_batch_tracing:
+        if auto_batch_tracing and _compression_enabled:
+            ...
+        elif auto_batch_tracing:
             self.tracing_queue: Optional[PriorityQueue] = PriorityQueue()
 
             threading.Thread(
@@ -1295,6 +1298,10 @@ def create_run(
                 self.tracing_queue.put(
                     TracingQueueItem(run_create["dotted_order"], serialized_op)
                 )
+            elif os.environ["COMP"]:
+                # Do something different
+                # Use existing serialized_run_dict
+
             else:
                 # Neither Rust nor Python batch ingestion is configured,
                 # fall back to the non-batch approach.