diff --git a/classes/callbacks.py b/classes/callbacks.py
index b05b3d3..af6fc52 100644
--- a/classes/callbacks.py
+++ b/classes/callbacks.py
@@ -9,7 +9,20 @@ class CallbackLanguage:
 
     @classmethod
     def from_callback(cls, callback: CallbackQuery):
+        """Parse callback query and extract language data from it.
+
+        ### Args:
+            * callback (`CallbackQuery`): Callback query got from user interaction.
+
+        ### Raises:
+            * `ValueError`: Raised when callback provided is not a language one.
+
+        ### Returns:
+            * `CallbackLanguage`: Parsed callback query.
+        """
         action, language = str(callback.data).split(":")
+
         if action.lower() != "language":
             raise ValueError("Callback provided is not a language callback")
+
         return cls(language)
diff --git a/classes/pyroclient.py b/classes/pyroclient.py
index 01888db..e7800ad 100644
--- a/classes/pyroclient.py
+++ b/classes/pyroclient.py
@@ -11,10 +11,10 @@ class PyroClient(LibPyroClient):
         """Find User by it's ID or User object.
 
         ### Args:
-            * user (`Union[int, User]`): ID or User object to extract ID from
+            * user (`Union[int, User]`): ID or User object to extract ID from.
 
         ### Returns:
-            * `PyroUser`: PyroUser object
+            * `PyroUser`: User in database representation.
         """
 
         return (
diff --git a/classes/pyrouser.py b/classes/pyrouser.py
index 527d72a..2fb9b73 100644
--- a/classes/pyrouser.py
+++ b/classes/pyrouser.py
@@ -21,6 +21,18 @@ class PyroUser:
 
     @classmethod
     async def find(cls, id: int, locale: Union[str, None] = None):
+        """Find user in database and create new record if user does not exist.
+
+        ### Args:
+            * id (`int`): User's Telegram ID
+            * locale (`Union[str, None]`, *optional*): User's locale. Defaults to `None`.
+
+        ### Raises:
+            * `RuntimeError`: Raised when user entry after insertion could not be found.
+
+        ### Returns:
+            * `PyroUser`: User with its database data.
+        """
         db_entry = await col_users.find_one({"id": id})
 
         if db_entry is None:
@@ -33,10 +45,10 @@ class PyroUser:
         return cls(**db_entry)
 
     async def update_locale(self, locale: Union[str, None]) -> None:
-        """Change user's locale stored in the database
+        """Change user's locale stored in the database.
 
         ### Args:
-            * locale (`Union[str, None]`): New locale to be set
+            * locale (`Union[str, None]`): New locale to be set.
         """
         logger.debug("%s's locale has been set to %s", self.id, locale)
         await col_users.update_one({"_id": self._id}, {"$set": {"locale": locale}})
diff --git a/modules/database.py b/modules/database.py
index 07f32e0..bdfacdb 100644
--- a/modules/database.py
+++ b/modules/database.py
@@ -1,9 +1,11 @@
 """Module that provides all database collections"""
 
-from async_pymongo import AsyncClient
+from typing import Any, Mapping
+
+from async_pymongo import AsyncClient, AsyncCollection, AsyncDatabase
 from libbot.sync import config_get
 
-db_config = config_get("database")
+db_config: Mapping[str, Any] = config_get("database")
 
 if db_config["user"] is not None and db_config["password"] is not None:
     con_string = "mongodb://{0}:{1}@{2}:{3}/{4}".format(
@@ -19,6 +21,6 @@ else:
     )
 
 db_client = AsyncClient(con_string)
-db = db_client.get_database(name=db_config["name"])
+db: AsyncDatabase = db_client.get_database(name=db_config["name"])
 
-col_users = db.get_collection("users")
+col_users: AsyncCollection = db.get_collection("users")
diff --git a/plugins/language.py b/plugins/language.py
index 72c59b5..673b72b 100644
--- a/plugins/language.py
+++ b/plugins/language.py
@@ -1,3 +1,5 @@
+from typing import List
+
 from pykeyboard import InlineButton, InlineKeyboard
 from pyrogram import filters
 from pyrogram.types import CallbackQuery, Message
@@ -13,7 +15,7 @@ async def command_language(app: PyroClient, message: Message):
     user = await app.find_user(message.from_user)
 
     keyboard = InlineKeyboard(row_width=2)
-    buttons = []
+    buttons: List[InlineButton] = []
 
     for locale, data in app.in_every_locale("metadata").items():
         buttons.append(