diff --git a/openbookr/db.py b/openbookr/db.py
new file mode 100644
index 0000000..30c9fa0
--- /dev/null
+++ b/openbookr/db.py
@@ -0,0 +1,63 @@
+# -*- coding: utf-8 -*-
+from typing import Iterable
+
+##################
+# DataBase logic #
+##################
+
+from openbookr.ABC import IDataBase
+from openbookr.models import Book
+
+
+class SQLiteEngine(object):
+    ...
+
+
+class SQlite(IDataBase, SQLiteEngine):
+
+    async def authors(self) -> Iterable:
+        ...
+
+    async def genres(self) -> Iterable:
+        ...
+
+    async def tags(self) -> Iterable:
+        ...
+
+    async def add_book(self, book: Book) -> None:
+        ...
+
+    async def get_book(self, book_id: int) -> Book:
+        ...
+
+    async def del_book(self, book_id: int) -> None:
+        ...
+
+    async def update_book(self, book_id: int, updated_book: Book) -> None:
+        ...
+
+    async def book_list(
+        self,
+        author: str | None = None,
+        tags: Iterable | None = None,
+        genres: Iterable | None = None,
+    ) -> Iterable:
+        ...
+
+    async def add_genre(self, genre: str) -> None:
+        ...
+
+    async def add_tag(self, tag: str) -> None:
+        ...
+
+    async def del_genre(self, genre_id: int) -> None:
+        ...
+
+    async def del_tag(self, tag_id: int) -> None:
+        ...
+
+    async def add_author(self, author: str) -> None:
+        ...
+
+    async def del_author(self, author_id: int) -> None:
+        ...