diff --git a/docs/source/autodoc/engineer.rst b/docs/source/autodoc/engineer.rst
index 9ce9fdc3..e42beb8c 100644
--- a/docs/source/autodoc/engineer.rst
+++ b/docs/source/autodoc/engineer.rst
@@ -21,6 +21,14 @@
 ----------------------------------------------
 
 .. automodule:: royalnet.engineer.sentry
+   :imported-members:
+
+
+``filter`` - Fluent filtering asyncio queue
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. automodule:: royalnet.engineer.sentry.filter
+   :imported-members:
 
 
 ``dispenser`` - Function parameter validation
diff --git a/royalnet/engineer/exc.py b/royalnet/engineer/exc.py
index 07bb9e99..7c18c7b3 100644
--- a/royalnet/engineer/exc.py
+++ b/royalnet/engineer/exc.py
@@ -46,3 +46,30 @@ class OutTeleporterError(TeleporterError):
     """
     The return value validation failed.
     """
+
+
+class SentryError(EngineerException):
+    """
+    An error related to the :mod:`royalnet.engineer.sentry`.
+    """
+
+
+class FilterError(SentryError):
+    """
+    An error related to the :class:`royalnet.engineer.sentry.Filter`.
+    """
+
+
+class Discard(FilterError):
+    """
+    Discard the object from the queue.
+    """
+    def __init__(self, obj, message):
+        self.obj = obj
+        self.message = message
+
+    def __repr__(self):
+        return f"<Discard>"
+
+    def __str__(self):
+        return f"Discarded {self.obj}: {self.message}"
diff --git a/royalnet/engineer/sentry.py b/royalnet/engineer/sentry.py
deleted file mode 100644
index 8b3d3acd..00000000
--- a/royalnet/engineer/sentry.py
+++ /dev/null
@@ -1,21 +0,0 @@
-from royalnet.royaltyping import *
-import logging
-import asyncio
-
-log = logging.getLogger(__name__)
-
-
-class Sentry:
-    """
-    A class that allows using the ``await`` keyword to suspend a command execution until a new message is received.
-    """
-
-    def __init__(self):
-        self.queue = asyncio.queues.Queue()
-
-    def __repr__(self):
-        return f"<Sentry, {self.queue.qsize()} items queued>"
-
-    async def wait_for_item(self) -> Any:
-        log.debug("Waiting for an item...")
-        return await self.queue.get()
diff --git a/royalnet/engineer/sentry/__init__.py b/royalnet/engineer/sentry/__init__.py
new file mode 100644
index 00000000..ef4d371e
--- /dev/null
+++ b/royalnet/engineer/sentry/__init__.py
@@ -0,0 +1 @@
+from .sentry import *
diff --git a/royalnet/engineer/sentry/filter.py b/royalnet/engineer/sentry/filter.py
new file mode 100644
index 00000000..e3c2601c
--- /dev/null
+++ b/royalnet/engineer/sentry/filter.py
@@ -0,0 +1,167 @@
+"""
+.. note:: I'm not sure about this module. It doesn't seem to be really pythonic. It will probably be deprecated in the
+          future...
+"""
+
+from __future__ import annotations
+from royalnet.royaltyping import *
+import functools
+import logging
+
+from engineer import exc, blueprints
+
+log = logging.getLogger(__name__)
+
+
+class Filter:
+    """
+    A fluent interface for filtering data.
+    """
+
+    def __init__(self, func: Callable):
+        self.func: Callable = func
+
+    async def get(self) -> Any:
+        """
+        Wait until an :class:`object` leaves the queue and passes through the filter, then return it.
+
+        :return: The :class:`object` which entered the queue.
+        """
+        while True:
+            try:
+                result = await self.func(None)
+            except exc.Discard as e:
+                log.debug(str(e))
+                continue
+            else:
+                log.debug(f"Dequeued {result}")
+                return result
+
+    @staticmethod
+    def _deco_type(t: type):
+        def decorator(func):
+            @functools.wraps(func)
+            def decorated(obj):
+                result: Any = func(obj)
+                if not isinstance(result, t):
+                    raise exc.Discard(result, f"Not instance of type {t}")
+                return result
+            return decorated
+        return decorator
+
+    def type(self, t: type) -> Filter:
+        """
+        :exc:`exc.Discard` all objects that are not an instance of ``t``.
+
+        :param t: The type that objects should be instances of.
+        :return: A new :class:`Filter` with the new requirements.
+        """
+        return self.__class__(self._deco_type(t)(self.func))
+
+    def msg(self) -> Filter:
+        """
+        :exc:`exc.Discard` all objects that are not an instance of :class:`.blueprints.Message`.
+
+        :return: A new :class:`Filter` with the new requirements.
+        """
+        return self.__class__(self._deco_type(blueprints.Message)(self.func))
+
+    @staticmethod
+    def _deco_requires(*fields):
+        def decorator(func):
+            @functools.wraps(func)
+            def decorated(obj):
+                result: blueprints.Blueprint = func(obj)
+                try:
+                    result.requires(*fields)
+                except exc.NotAvailableError:
+                    raise exc.Discard(result, "Missing data")
+                except AttributeError:
+                    raise exc.Discard(result, "Missing .requires() method")
+                return result
+            return decorated
+        return decorator
+
+    def requires(self, *fields) -> Filter:
+        """
+        Test an object's fields by using its ``.requires()`` method (expecting it to be
+        :meth:`.blueprints.Blueprint.requires`) and discard everything that does not pass the check.
+
+        :param fields: The fields to test for.
+        :return: A new :class:`Filter` with the new requirements.
+        """
+        return self.__class__(self._deco_requires(*fields)(self.func))
+
+    @staticmethod
+    def _deco_text():
+        def decorator(func):
+            @functools.wraps(func)
+            def decorated(obj):
+                result: blueprints.Message = func(obj)
+                try:
+                    text = result.text()
+                except exc.NotAvailableError:
+                    raise exc.Discard(result, "No text")
+                except AttributeError:
+                    raise exc.Discard(result, "Missing text method")
+                return text
+            return decorated
+        return decorator
+
+    def text(self) -> Filter:
+        """
+        Get the text of the passed object by using its ``.text()`` method (expecting it to be
+        :meth:`.blueprints.Message.text`), while discarding all objects that don't have a text.
+
+        :return: A new :class:`Filter` with the new requirements.
+        """
+        return self.__class__(self._deco_text()(self.func))
+
+    @staticmethod
+    def _deco_regex(pattern: Pattern):
+        def decorator(func):
+            @functools.wraps(func)
+            def decorated(obj):
+                result: str = func(obj)
+                if match := pattern.match(result):
+                    return match
+                else:
+                    raise exc.Discard(result, f"Text didn't match pattern {pattern}")
+            return decorated
+        return decorator
+
+    def regex(self, pattern: Pattern):
+        """
+        Apply a regex over an object's text (obtained through its ``.text()`` method, expecting it to be
+        :meth:`.blueprints.Message.text`) and discard the object if it does not match.
+
+        :param pattern: The pattern that should be matched by the text.
+        :return: A new :class:`Filter` with the new requirements.
+        """
+        return self.__class__(self._deco_regex(pattern)(self.func))
+
+    @staticmethod
+    def _deco_choices(*choices):
+        def decorator(func):
+            @functools.wraps(func)
+            def decorated(obj: blueprints.Message):
+                result = func(obj)
+                if result not in choices:
+                    raise exc.Discard(result, "Not a valid choice")
+                return result
+            return decorated
+        return decorator
+
+    def choices(self, *choices):
+        """
+        Ensure an object is in the ``choices`` list, discarding the object otherwise.
+
+        :param choices: The pattern that should be matched by the text.
+        :return: A new :class:`Filter` with the new requirements.
+        """
+        return self.__class__(self._deco_choices(*choices)(self.func))
+
+
+__all__ = (
+    "Filter",
+)
diff --git a/royalnet/engineer/sentry/sentry.py b/royalnet/engineer/sentry/sentry.py
new file mode 100644
index 00000000..229d031a
--- /dev/null
+++ b/royalnet/engineer/sentry/sentry.py
@@ -0,0 +1,51 @@
+from __future__ import annotations
+from royalnet.royaltyping import *
+import logging
+import asyncio
+
+from .filter import Filter
+
+log = logging.getLogger(__name__)
+
+
+class Sentry:
+    """
+    A class that allows using the ``await`` keyword to suspend a command execution until a new message is received.
+    """
+
+    QUEUE_SIZE = 12
+    """
+    The size of the object :attr:`.queue`.
+    """
+
+    def __init__(self):
+        self.queue: asyncio.Queue = asyncio.Queue(maxsize=12)
+        """
+        An object queue where incoming :class:`object` are stored.
+        """
+
+    def __repr__(self):
+        return f"<Sentry>"
+
+    async def get(self, *_, **__) -> Any:
+        """
+        Wait until an :class:`object` leaves the queue, then return it.
+
+        :return: The :class:`object` which entered the queue.
+        """
+        return await self.queue.get()
+
+    async def filter(self):
+        """
+        Create a :class:`.filters.Filter` object, which can be configured through its fluent interface.
+
+        Remember to call ``.get()`` on the end of the chain.
+
+        :return: The created :class:`.filters.Filter`.
+        """
+        return Filter(self.get)
+
+
+__all__ = (
+    "Sentry",
+)