diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index d1e0831..5c4b513 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -15,10 +15,11 @@ repos:
     hooks:
     - id: flake8
 -   repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.3.0
+    rev: v1.6.1
     hooks:
     -   id: mypy
-        files: ^aiostream/
+        files: ^(?!tests)
+        types: [python]
 - repo: https://github.com/astral-sh/ruff-pre-commit
   # Ruff version.
   rev: v0.0.272
diff --git a/aiostream/core.py b/aiostream/core.py
index e224a8e..a11f082 100644
--- a/aiostream/core.py
+++ b/aiostream/core.py
@@ -109,14 +109,14 @@ def __await__(self) -> Generator[Any, None, T]:
         """
         return wait_stream(self).__await__()
 
-    def __or__(self, func: Callable[[BaseStream[T]], BaseStream[X]]) -> BaseStream[X]:
+    def __or__(self, func: Callable[[BaseStream[T]], X]) -> X:
         """Pipe protocol.
 
         Allow to pipe stream operators.
         """
         return func(self)
 
-    def __add__(self, value: BaseStream[X]) -> BaseStream[Union[X, T]]:
+    def __add__(self, value: AsyncIterable[X]) -> Stream[Union[X, T]]:
         """Addition protocol.
 
         Concatenate with a given asynchronous sequence.
@@ -125,7 +125,7 @@ def __add__(self, value: BaseStream[X]) -> BaseStream[Union[X, T]]:
 
         return chain(self, value)
 
-    def __getitem__(self, value: Union[int, slice]) -> BaseStream[T]:
+    def __getitem__(self, value: Union[int, slice]) -> Stream[T]:
         """Get item protocol.
 
         Accept index or slice to extract the corresponding item(s)
@@ -276,7 +276,9 @@ def raw(
     ) -> AsyncIterator[T]:
         ...
 
-    def pipe(self, source: AsyncIterable[A]) -> Stream[T]:
+    def pipe(
+        self, *args: P.args, **kwargs: P.kwargs
+    ) -> Callable[[AsyncIterable[A]], Stream[T]]:
         ...
 
 
@@ -555,7 +557,7 @@ def pipe(
         "__doc__": doc,
         "raw": staticmethod(raw),
         "original": staticmethod(original),
-        "pipe": classmethod(pipe),
+        "pipe": classmethod(pipe),  # type: ignore[arg-type]
     }
 
     # Create operator class
diff --git a/aiostream/pipe.py b/aiostream/pipe.py
index 1dd44bd..c27e101 100644
--- a/aiostream/pipe.py
+++ b/aiostream/pipe.py
@@ -3,19 +3,37 @@
 
 from . import stream
 
-__all__: list[str] = []
-
-
-def update_pipe_module() -> None:
-    """Populate the pipe module dynamically."""
-    module_dir = __all__
-    operators = stream.__dict__
-    for key, value in operators.items():
-        if getattr(value, "pipe", None):
-            globals()[key] = value.pipe
-            if key not in module_dir:
-                module_dir.append(key)
-
-
-# Populate the module
-update_pipe_module()
+accumulate = stream.accumulate.pipe
+action = stream.action.pipe
+amap = stream.amap.pipe
+chain = stream.chain.pipe
+chunks = stream.chunks.pipe
+concat = stream.concat.pipe
+concatmap = stream.concatmap.pipe
+cycle = stream.cycle.pipe
+delay = stream.delay.pipe
+dropwhile = stream.dropwhile.pipe
+enumerate = stream.enumerate.pipe
+filter = stream.filter.pipe
+flatmap = stream.flatmap.pipe
+flatten = stream.flatten.pipe
+getitem = stream.getitem.pipe
+list = stream.list.pipe
+map = stream.map.pipe
+merge = stream.merge.pipe
+print = stream.print.pipe
+reduce = stream.reduce.pipe
+skip = stream.skip.pipe
+skiplast = stream.skiplast.pipe
+smap = stream.smap.pipe
+spaceout = stream.spaceout.pipe
+starmap = stream.starmap.pipe
+switch = stream.switch.pipe
+switchmap = stream.switchmap.pipe
+take = stream.take.pipe
+takelast = stream.takelast.pipe
+takewhile = stream.takewhile.pipe
+timeout = stream.timeout.pipe
+until = stream.until.pipe
+zip = stream.zip.pipe
+ziplatest = stream.ziplatest.pipe
diff --git a/examples/demo.py b/examples/demo.py
index 1c6ca32..e1352c6 100644
--- a/examples/demo.py
+++ b/examples/demo.py
@@ -3,12 +3,16 @@
 from aiostream import pipe, stream
 
 
-async def main():
+def square(x: int, *_: int) -> int:
+    return x**2
+
+
+async def main() -> None:
     # Create a counting stream with a 0.2 seconds interval
     xs = stream.count(interval=0.2)
 
     # Operators can be piped using '|'
-    ys = xs | pipe.map(lambda x: x**2)
+    ys = xs | pipe.map(square)
 
     # Streams can be sliced
     zs = ys[1:10:2]
diff --git a/examples/extra.py b/examples/extra.py
index bab5e9c..5a2084e 100644
--- a/examples/extra.py
+++ b/examples/extra.py
@@ -1,11 +1,14 @@
 import asyncio
 import random as random_module
+from typing import AsyncIterable, AsyncIterator
 
 from aiostream import operator, pipable_operator, pipe, streamcontext
 
 
 @operator
-async def random(offset=0.0, width=1.0, interval=0.1):
+async def random(
+    offset: float = 0.0, width: float = 1.0, interval: float = 0.1
+) -> AsyncIterator[float]:
     """Generate a stream of random numbers."""
     while True:
         await asyncio.sleep(interval)
@@ -13,7 +16,9 @@ async def random(offset=0.0, width=1.0, interval=0.1):
 
 
 @pipable_operator
-async def power(source, exponent):
+async def power(
+    source: AsyncIterable[float], exponent: float | int
+) -> AsyncIterator[float]:
     """Raise the elements of an asynchronous sequence to the given power."""
     async with streamcontext(source) as streamer:
         async for item in streamer:
@@ -21,12 +26,12 @@ async def power(source, exponent):
 
 
 @pipable_operator
-def square(source):
+def square(source: AsyncIterable[float]) -> AsyncIterator[float]:
     """Square the elements of an asynchronous sequence."""
     return power.raw(source, 2)
 
 
-async def main():
+async def main() -> None:
     xs = (
         random()  # Stream random numbers
         | square.pipe()  # Square the values
diff --git a/examples/norm_server.py b/examples/norm_server.py
index 5aa955a..a1283f2 100644
--- a/examples/norm_server.py
+++ b/examples/norm_server.py
@@ -14,6 +14,7 @@
     [...]
 """
 
+import math
 import asyncio
 
 from aiostream import pipe, stream
@@ -40,22 +41,24 @@
 # Client handler
 
 
-async def euclidean_norm_handler(reader, writer):
+async def euclidean_norm_handler(
+    reader: asyncio.StreamReader, writer: asyncio.StreamWriter
+) -> None:
     # Define lambdas
-    def strip(x):
+    def strip(x: bytes, *_: object) -> str:
         return x.decode().strip()
 
-    def nonempty(x):
+    def nonempty(x: str) -> bool:
         return x != ""
 
-    def square(x):
+    def square(x: float, *_: object) -> float:
         return x**2
 
-    def write_cursor(x):
+    def write_cursor(_: float) -> None:
         return writer.write(b"> ")
 
-    def square_root(x):
-        return x**0.5
+    def square_root(x: float, *_: object) -> float:
+        return math.sqrt(x)
 
     # Create awaitable
     handle_request = (
@@ -67,7 +70,7 @@ def square_root(x):
         | pipe.map(square)
         | pipe.print("square: {:.2f}")
         | pipe.action(write_cursor)
-        | pipe.accumulate(initializer=0)
+        | pipe.accumulate(initializer=0.0)
         | pipe.map(square_root)
         | pipe.print("norm -> {:.2f}")
     )
@@ -86,7 +89,7 @@ def square_root(x):
 # Main function
 
 
-async def main(bind="127.0.0.1", port=8888):
+async def main(bind: str = "127.0.0.1", port: int = 8888) -> None:
     # Start the server
     server = await asyncio.start_server(euclidean_norm_handler, bind, port)
 
diff --git a/examples/preserve.py b/examples/preserve.py
index d6faf48..9fedb0b 100644
--- a/examples/preserve.py
+++ b/examples/preserve.py
@@ -1,10 +1,11 @@
 import asyncio
+from typing import AsyncIterator
 
 from aiostream import operator, stream
 
 
-async def main():
-    async def agen():
+async def main() -> None:
+    async def agen() -> AsyncIterator[int]:
         yield 1
         yield 2
         yield 3
diff --git a/examples/simple.py b/examples/simple.py
index dd9569d..2d5d74c 100644
--- a/examples/simple.py
+++ b/examples/simple.py
@@ -3,14 +3,22 @@
 from aiostream import pipe, stream
 
 
-async def main():
+def is_odd(x: int) -> bool:
+    return x % 2 == 1
+
+
+def square(x: int, *_: object) -> int:
+    return x**2
+
+
+async def main() -> None:
     # This stream computes 11² + 13² in 1.5 second
     xs = (
         stream.count(interval=0.1)  # Count from zero every 0.1 s
         | pipe.skip(10)  # Skip the first 10 numbers
         | pipe.take(5)  # Take the following 5
-        | pipe.filter(lambda x: x % 2)  # Keep odd numbers
-        | pipe.map(lambda x: x**2)  # Square the results
+        | pipe.filter(is_odd)  # Keep odd numbers
+        | pipe.map(square)  # Square the results
         | pipe.accumulate()  # Add the numbers together
     )
     print("11² + 13² = ", await xs)
diff --git a/setup.cfg b/setup.cfg
index b939c7e..e9876ef 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -16,7 +16,7 @@ ignore = F401, F403, E731, W503, E501, E203
 
 [mypy]
 strict = True
-packages = aiostream
+packages = aiostream, examples
 
 [mypy-aiostream.test_utils]
 ignore_errors = True
diff --git a/tests/test_pipe.py b/tests/test_pipe.py
new file mode 100644
index 0000000..66f3596
--- /dev/null
+++ b/tests/test_pipe.py
@@ -0,0 +1,10 @@
+from aiostream import stream, pipe
+
+
+def test_pipe_module():
+    for name in dir(stream):
+        obj = getattr(stream, name)
+        pipe_method = getattr(obj, "pipe", None)
+        if pipe_method is None:
+            continue
+        assert getattr(pipe, name) == pipe_method