diff --git a/addon_examples/xfer_example.py b/addon_examples/xfer_example.py
index 395b662..b22d247 100644
--- a/addon_examples/xfer_example.py
+++ b/addon_examples/xfer_example.py
@@ -8,7 +8,7 @@ from hippolyzer.lib.proxy.commands import handle_command
 from hippolyzer.lib.proxy.message import ProxiedMessage
 from hippolyzer.lib.proxy.region import ProxiedRegion
 from hippolyzer.lib.proxy.sessions import Session
-from hippolyzer.lib.proxy.templates import XferFilePath
+from hippolyzer.lib.proxy.templates import XferFilePath, AssetType
 
 
 class XferExampleAddon(BaseAddon):
diff --git a/hippolyzer/lib/base/message/message.py b/hippolyzer/lib/base/message/message.py
index 7e63dd3..4323a38 100644
--- a/hippolyzer/lib/base/message/message.py
+++ b/hippolyzer/lib/base/message/message.py
@@ -40,7 +40,7 @@ class Block:
     """
     __slots__ = ('name', 'size', 'vars', 'message_name', '_ser_cache', 'fill_missing',)
 
-    def __init__(self, name, /, fill_missing=False, **kwargs):
+    def __init__(self, name, *, /, fill_missing=False, **kwargs):
         self.name = name
         self.size = 0
         self.message_name: Optional[str] = None
diff --git a/hippolyzer/lib/proxy/xfer_manager.py b/hippolyzer/lib/proxy/xfer_manager.py
index 54ac25e..7c979ce 100644
--- a/hippolyzer/lib/proxy/xfer_manager.py
+++ b/hippolyzer/lib/proxy/xfer_manager.py
@@ -25,7 +25,7 @@ _XFER_MESSAGES = {"AbortXfer", "ConfirmXferPacket", "RequestXfer", "SendXferPack
 
 
 class Xfer:
-    def __init__(self, xfer_id: int):
+    def __init__(self, xfer_id: Optional[int] = None):
         super().__init__()
         self.xfer_id: Optional[int] = xfer_id
         self.chunks: Dict[int, bytes] = {}
@@ -144,3 +144,77 @@ class XferManager:
         xfer.chunks[packet_id.PacketID] = packet_data
         if packet_id.IsEOF and not xfer.done():
             xfer.mark_done()
+
+    def upload_asset(
+            self,
+            asset_type: AssetType,
+            data: bytes,
+            store_local: bool = False,
+            temp_file: bool = False,
+            transaction_id: Optional[UUID] = None,
+    ):
+        """Upload an asset through the Xfer upload path"""
+        if not transaction_id:
+            transaction_id = UUID.random()
+        xfer = Xfer()
+        chunk_num = 0
+        # prepend the length expected length
+        data = TemplateDataPacker.pack(len(data), MsgType.MVT_S32) + data
+        while data:
+            xfer.chunks[chunk_num] = data[:1200]
+            data = data[1200:]
+        self._region.circuit.send_message(ProxiedMessage(
+            "AssetUploadRequest",
+            Block(
+                "AssetBlock",
+                TransactionID=transaction_id,
+                Type=asset_type,
+                Tempfile=temp_file,
+                StoreLocal=store_local,
+                # Can shove in here for assets smaller than 1200 bytes, always
+                # use the long, Xfer path for now.
+                AssetData=b'',
+            )
+        ))
+        fut = asyncio.Future()
+        asyncio.create_task(self._pump_asset_upload(xfer, transaction_id, fut))
+        return fut
+
+    async def _pump_asset_upload(self, xfer: Xfer, transaction_id: UUID, fut: asyncio.Future):
+        message_handler = self._region.message_handler
+        # We'll receive an Xfer request for the asset we're uploading.
+        # asset ID is determined by hashing secure session ID with chosen transaction ID.
+        asset_id: UUID = self._region.session().tid_to_assetid(transaction_id)
+        try:
+            def request_predicate(request_msg: ProxiedMessage):
+                return request_msg["XferID"]["VFileID"] == asset_id
+            msg = await message_handler.wait_for(
+                'RequestXfer', predicate=request_predicate, timeout=5000)
+            xfer.xfer_id = msg["XferID"]["ID"]
+
+            packet_id = 0
+            # TODO: No resend yet. If it's lost, it's lost.
+            while xfer.chunks:
+                chunk = xfer.chunks.pop(packet_id)
+                # EOF if there are no chunks left
+                packet_val = XferPacket(PacketID=packet_id, IsEOF=not bool(xfer.chunks))
+                self._region.circuit.send_message(ProxiedMessage(
+                    "SendXferPacket",
+                    Block("XferID", ID=xfer.xfer_id, Packet_=packet_val),
+                    Block("DataPacket", Data=chunk),
+                ))
+                # Don't care about the value, just want to know it was confirmed.
+                await message_handler.wait_for(
+                    "ConfirmXferPacket", predicate=xfer.is_our_message, timeout=5000)
+                packet_id += 1
+
+            def complete_predicate(complete_msg: ProxiedMessage):
+                return complete_msg["AssetBlock"]["UUID"] == asset_id
+            msg = await message_handler.wait_for('AssetUploadComplete', predicate=complete_predicate)
+            if msg["AssetBlock"]["Success"] == 1:
+                fut.set_result(asset_id)
+            else:
+                fut.set_exception(RuntimeError(f"Xfer for transaction {transaction_id} failed"))
+
+        except asyncio.TimeoutError as e:
+            fut.set_exception(e)