diff --git a/backend/app/database.py b/backend/app/database.py
new file mode 100644
index 0000000..815741b
--- /dev/null
+++ b/backend/app/database.py
@@ -0,0 +1,23 @@
+from collections.abc import Generator
+
+from sqlalchemy import create_engine
+from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker
+
+from .config import settings
+
+
+class Base(DeclarativeBase):
+    """Базовый класс SQLAlchemy-моделей."""
+
+
+engine = create_engine(settings.database_url, pool_pre_ping=True)
+SessionLocal = sessionmaker(bind=engine, autoflush=False, autocommit=False)
+
+
+def get_db() -> Generator[Session, None, None]:
+    """Открывает сессию БД для одного HTTP-запроса."""
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()