diff --git a/findmy/util/session.py b/findmy/util/session.py
new file mode 100644
index 0000000..a545292
--- /dev/null
+++ b/findmy/util/session.py
@@ -0,0 +1,144 @@
+"""Logic related to serializable classes."""
+
+from __future__ import annotations
+
+import random
+from typing import TYPE_CHECKING, Any, Generic, Self, TypeVar, Union
+
+from findmy.util.abc import Closable, Serializable
+
+if TYPE_CHECKING:
+    from pathlib import Path
+    from types import TracebackType
+
+_S = TypeVar("_S", bound=Serializable)
+_SC = TypeVar("_SC", bound=Union[Serializable, Closable])
+
+
+class _BaseSessionManager(Generic[_SC]):
+    """Base class for session managers."""
+
+    def __init__(self) -> None:
+        self._sessions: dict[_SC, str | Path | None] = {}
+
+    def _add(self, obj: _SC, path: str | Path | None) -> None:
+        self._sessions[obj] = path
+
+    def remove(self, obj: _SC) -> None:
+        self._sessions.pop(obj, None)
+
+    def save(self) -> None:
+        for obj, path in self._sessions.items():
+            if isinstance(obj, Serializable):
+                obj.to_json(path)
+
+    async def close(self) -> None:
+        for obj in self._sessions:
+            if isinstance(obj, Closable):
+                await obj.close()
+
+    async def save_and_close(self) -> None:
+        for obj, path in self._sessions.items():
+            if isinstance(obj, Serializable):
+                obj.to_json(path)
+            if isinstance(obj, Closable):
+                await obj.close()
+
+    def get_random(self) -> _SC:
+        if not self._sessions:
+            msg = "No objects in the session manager."
+            raise ValueError(msg)
+        return random.choice(list(self._sessions.keys()))  # noqa: S311
+
+    def __len__(self) -> int:
+        return len(self._sessions)
+
+    def __enter__(self) -> Self:
+        return self
+
+    def __exit__(
+        self,
+        _exc_type: type[BaseException] | None,
+        _exc_val: BaseException | None,
+        _exc_tb: TracebackType | None,
+    ) -> None:
+        self.save()
+
+
+class MixedSessionManager(_BaseSessionManager[Union[Serializable, Closable]]):
+    """Allows any Serializable or Closable object."""
+
+    def new(
+        self,
+        c_type: type[_SC],
+        path: str | Path | None = None,
+        /,
+        *args: Any,  # noqa: ANN401
+        **kwargs: Any,  # noqa: ANN401
+    ) -> _SC:
+        """Add an object to the manager by instantiating it using its constructor."""
+        obj = c_type(*args, **kwargs)
+        if isinstance(obj, Serializable) and path is not None:
+            obj.to_json(path)
+        self._add(obj, path)
+        return obj
+
+    def add_from_json(
+        self,
+        c_type: type[_S],
+        path: str | Path,
+        /,
+        **kwargs: Any,  # noqa: ANN401
+    ) -> _S:
+        """Add an object to the manager by deserializing it from its JSON representation."""
+        obj = c_type.from_json(path, **kwargs)
+        self._add(obj, path)
+        return obj
+
+    def add(self, obj: Serializable | Closable, path: str | Path | None = None, /) -> None:
+        """Add an object to the session manager."""
+        self._add(obj, path)
+
+
+class UniformSessionManager(Generic[_SC], _BaseSessionManager[_SC]):
+    """Only allows a single type of Serializable object."""
+
+    def __init__(self, obj_type: type[_SC]) -> None:
+        """Create a new session manager."""
+        super().__init__()
+        self._obj_type = obj_type
+
+    def new(
+        self,
+        path: str | Path | None = None,
+        /,
+        *args: Any,  # noqa: ANN401
+        **kwargs: Any,  # noqa: ANN401
+    ) -> _SC:
+        """Add an object to the manager by instantiating it using its constructor."""
+        obj = self._obj_type(*args, **kwargs)
+        if isinstance(obj, Serializable) and path is not None:
+            obj.to_json(path)
+        self._add(obj, path)
+        return obj
+
+    def add_from_json(
+        self,
+        path: str | Path,
+        /,
+        **kwargs: Any,  # noqa: ANN401
+    ) -> _SC:
+        """Add an object to the manager by deserializing it from its JSON representation."""
+        if not issubclass(self._obj_type, Serializable):
+            msg = "Can only add objects of type Serializable."
+            raise TypeError(msg)
+        obj = self._obj_type.from_json(path, **kwargs)
+        self._add(obj, path)
+        return obj
+
+    def add(self, obj: _SC, path: str | Path | None = None, /) -> None:
+        """Add an object to the session manager."""
+        if not isinstance(obj, self._obj_type):
+            msg = f"Object must be of type {self._obj_type.__name__}"
+            raise TypeError(msg)
+        self._add(obj, path)