diff --git a/kioss/__init__.py b/kioss/__init__.py
index 693c771..c8d4c57 100644
--- a/kioss/__init__.py
+++ b/kioss/__init__.py
@@ -1,4 +1,4 @@
-from kioss._plan import SourcePipe as Pipe
+from kioss._plan import APipe as Pipe
 from kioss._util import LOGGER
 from kioss import _plan, _visitor
 _plan.APipe.ITERATOR_GENERATING_VISITOR_CLASS = _visitor.IteratorGeneratingVisitor
\ No newline at end of file
diff --git a/kioss/_concurrent_exec.py b/kioss/_concurrent_exec.py
index 39fbebf..6477fa4 100644
--- a/kioss/_concurrent_exec.py
+++ b/kioss/_concurrent_exec.py
@@ -86,7 +86,7 @@ def __iter__(self) -> Iterator[Union[R, _ExceptionContainer]]:
 
 
 
-class ThreadedFlatteningIteratorWrapper(ThreadedMappingIteratorWrapper[Union[T, _Skip]]):
+class ThreadedFlatteningIteratorWrapper(ThreadedMappingIteratorWrapper[T]):
     _SKIP: _Skip = _Skip()
     _BUFFER_SIZE = 32
     _INIT_RETRY_BACKFOFF = 0.0005
diff --git a/kioss/_plan.py b/kioss/_plan.py
index 9ec0461..ac45d22 100644
--- a/kioss/_plan.py
+++ b/kioss/_plan.py
@@ -2,6 +2,8 @@
 from typing import (
     Any,
     Callable,
+    Collection,
+    Generic,
     Iterable,
     Iterator,
     List,
@@ -22,7 +24,7 @@
 
 class APipe(Iterable[T], ABC):
     ITERATOR_GENERATING_VISITOR_CLASS: "Optional[Type[_visitor.IteratorGeneratingVisitor]]" = None
-    def __init__(self, upstream: "APipe[U]"):
+    def __init__(self, upstream: "APipe"):
         self.upstream = upstream
         if self.ITERATOR_GENERATING_VISITOR_CLASS is None:
             raise ValueError("ITERATOR_GENERATING_VISITOR_CLASS not instantiated")
@@ -238,6 +240,9 @@ def register_error_sample(error):
 
         return samples
 
+    @classmethod
+    def __rshift__(cls, source: Callable[[], Iterator[T]]) -> "SourcePipe[T]":
+        return SourcePipe(source)
 
 class SourcePipe(APipe[T]):
     def __init__(self, source: Callable[[], Iterator[T]]):
diff --git a/tests/test_legacy.py b/tests/test_legacy.py
index 2a4d495..b2ab58d 100644
--- a/tests/test_legacy.py
+++ b/tests/test_legacy.py
@@ -181,11 +181,11 @@ def store_error_types(error):
         # test rasing:
         self.assertRaises(
             ValueError,
-            Pipe([map(int, "12-3")].__iter__).flatten(n_threads=n_threads).collect,
+            Pipe([map(int, "12-3")].__iter__).flatten(n_threads=n_threads).collect, # type: ignore
         )
         self.assertRaises(
             ValueError,
-            Pipe(lambda: map(int, "-")).flatten(n_threads=n_threads).collect,
+            Pipe(lambda: map(int, "-")).flatten(n_threads=n_threads).collect,  # type: ignore
         )
 
     def test_add(self):
@@ -220,10 +220,11 @@ def test_map(self, n_threads: int):
             ),
             set(map(func, range(1, N))),
         )
+        l: List[List[int]] = [[1], [], [3]]
         self.assertSetEqual(
             set(
-                Pipe([[1], [], [3]].__iter__)
-                .map(iter)
+                Pipe(l.__iter__)
+                .map(lambda l: iter(l))
                 .map(next, n_threads=n_threads)
                 .catch(RuntimeError)
             ),
@@ -505,7 +506,7 @@ def test_invalid_source(self):
     @parameterized.expand([[1], [2], [3]])
     def test_invalid_flatten_upstream(self, n_threads: int):
         self.assertRaises(
-            TypeError, Pipe(range(3).__iter__).flatten(n_threads=n_threads).collect
+            TypeError, Pipe(range(3).__iter__).flatten(n_threads=n_threads).collect # type: ignore
         )
 
     def test_planning_and_execution_decoupling(self):