diff --git a/nonebot/adapters/__init__.py b/nonebot/adapters/__init__.py
index e8e5f2c3..5bd2e96f 100644
--- a/nonebot/adapters/__init__.py
+++ b/nonebot/adapters/__init__.py
@@ -3,6 +3,9 @@
 
 import abc
 from functools import reduce
+from dataclasses import dataclass
+
+# from pydantic.dataclasses import dataclass  # dataclass with validation
 
 from nonebot.config import Config
 from nonebot.drivers import BaseWebSocket
@@ -37,51 +40,65 @@ class BaseBot(abc.ABC):
         raise NotImplementedError
 
 
-class BaseMessageSegment(dict):
-
-    def __init__(self,
-                 type_: Optional[str] = None,
-                 data: Optional[Dict[str, str]] = None):
-        super().__init__()
-        if type_:
-            self.type = type_
-            self.data = data
-        else:
-            raise ValueError('The "type" field cannot be empty')
+@dataclass
+class BaseMessageSegment(abc.ABC):
+    type: str
+    data: Dict[str, str] = {}
 
+    @abc.abstractmethod
     def __str__(self):
         raise NotImplementedError
 
-    def __getitem__(self, item):
-        if item not in ("type", "data"):
-            raise KeyError(f'Key "{item}" is not allowed')
-        return super().__getitem__(item)
-
-    def __setitem__(self, key, value):
-        if key not in ("type", "data"):
-            raise KeyError(f'Key "{key}" is not allowed')
-        return super().__setitem__(key, value)
-
-    # TODO: __eq__ __add__
-
-    @property
-    def type(self) -> str:
-        return self["type"]
-
-    @type.setter
-    def type(self, value: str):
-        self["type"] = value
-
-    @property
-    def data(self) -> Dict[str, str]:
-        return self["data"]
-
-    @data.setter
-    def data(self, data: Optional[Dict[str, str]]):
-        self["data"] = data or {}
+    @abc.abstractmethod
+    def __add__(self, other):
+        raise NotImplementedError
 
 
-class BaseMessage(list):
+# class BaseMessageSegment(dict):
+
+#     def __init__(self,
+#                  type_: Optional[str] = None,
+#                  data: Optional[Dict[str, str]] = None):
+#         super().__init__()
+#         if type_:
+#             self.type = type_
+#             self.data = data
+#         else:
+#             raise ValueError('The "type" field cannot be empty')
+
+#     def __str__(self):
+#         raise NotImplementedError
+
+#     def __getitem__(self, item):
+#         if item not in ("type", "data"):
+#             raise KeyError(f'Key "{item}" is not allowed')
+#         return super().__getitem__(item)
+
+#     def __setitem__(self, key, value):
+#         if key not in ("type", "data"):
+#             raise KeyError(f'Key "{key}" is not allowed')
+#         return super().__setitem__(key, value)
+
+#     # TODO: __eq__ __add__
+
+#     @property
+#     def type(self) -> str:
+#         return self["type"]
+
+#     @type.setter
+#     def type(self, value: str):
+#         self["type"] = value
+
+#     @property
+#     def data(self) -> Dict[str, str]:
+#         return self["data"]
+
+#     @data.setter
+#     def data(self, data: Optional[Dict[str, str]]):
+#         self["data"] = data or {}
+
+
+class BaseMessage(list, abc.ABC):
 
     def __init__(self,
                  message: Union[str, BaseMessageSegment, "BaseMessage"] = None,
@@ -99,6 +116,7 @@ class BaseMessage(list):
         return ''.join((str(seg) for seg in self))
 
     @staticmethod
+    @abc.abstractmethod
     def _construct(msg: str) -> Iterable[BaseMessageSegment]:
         raise NotImplementedError
 
diff --git a/nonebot/adapters/cqhttp.py b/nonebot/adapters/cqhttp.py
index 7e2fc827..89dafcb3 100644
--- a/nonebot/adapters/cqhttp.py
+++ b/nonebot/adapters/cqhttp.py
@@ -99,6 +99,7 @@ class Bot(BaseBot):
 
 class MessageSegment(BaseMessageSegment):
 
+    @overrides(BaseMessageSegment)
     def __str__(self):
         type_ = self.type
         data = self.data.copy()
@@ -116,6 +117,10 @@ class MessageSegment(BaseMessageSegment):
         params = ",".join([f"{k}={escape(str(v))}" for k, v in data.items()])
         return f"[CQ:{type_}{',' if params else ''}{params}]"
 
+    @overrides(BaseMessageSegment)
+    def __add__(self, other) -> "Message":
+        return Message(self) + other
+
     @staticmethod
     def anonymous(ignore_failure: bool = False) -> "MessageSegment":
         return MessageSegment("anonymous", {"ignore": _b2s(ignore_failure)})
@@ -248,6 +253,7 @@ class MessageSegment(BaseMessageSegment):
 class Message(BaseMessage):
 
     @staticmethod
+    @overrides(BaseMessage)
     def _construct(msg: str) -> Iterable[MessageSegment]:
 
         def _iter_message() -> Iterable[Tuple[str, str]]:
diff --git a/nonebot/typing.py b/nonebot/typing.py
index cb798274..cfee1152 100644
--- a/nonebot/typing.py
+++ b/nonebot/typing.py
@@ -1,7 +1,6 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
-from abc import ABC
 from types import ModuleType
 from typing import TYPE_CHECKING
 from typing import Any, Set, List, Dict, Type, Tuple, Mapping
@@ -13,9 +12,9 @@ if TYPE_CHECKING:
     from nonebot.event import Event
 
 
-def overrides(InterfaceClass: ABC):
+def overrides(InterfaceClass: object):
 
-    def overrider(func):
+    def overrider(func: Callable) -> Callable:
         assert func.__name__ in dir(
             InterfaceClass), f"Error method: {func.__name__}"
         return func
diff --git a/pyproject.toml b/pyproject.toml
index 19f93c05..43973465 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,7 +25,7 @@ fastapi = "^0.58.1"
 uvicorn = "^0.11.5"
 pydantic = { extras = ["dotenv"], version = "^1.5.1" }
 apscheduler = { version = "^3.6.3", optional = true }
-nonebot-test = { version = "^0.1.0", optional = true }
+# nonebot-test = { version = "^0.1.0", optional = true }
 
 [tool.poetry.dev-dependencies]
 yapf = "^0.30.0"