diff --git a/src/habitmove/schema.py b/src/habitmove/schema.py
index 17272e8..c725648 100644
--- a/src/habitmove/schema.py
+++ b/src/habitmove/schema.py
@@ -1,7 +1,8 @@
 import sqlite3
+import sys
 
 
-def create_database(db_file: str) -> sqlite3.Connection:
+def create_database(db_file: str = ":memory:") -> sqlite3.Connection:
     """create a database connection to the SQLite database
         specified by db_file
     :param db_file: database file
@@ -13,10 +14,10 @@ def create_database(db_file: str) -> sqlite3.Connection:
         return conn
     except sqlite3.Error as e:
         print(e)
+        sys.exit(1)
 
 
-def create_tables(db):
-    c = db.cursor()
+def create_tables(c: sqlite3.Cursor):
     c.execute(
         """ CREATE TABLE IF NOT EXISTS Habits (
                                         id integer PRIMARY KEY AUTOINCREMENT,
@@ -49,8 +50,7 @@ def create_tables(db):
     )
 
 
-def create_constraints(db):
-    c = db.cursor()
+def create_constraints(c: sqlite3.Cursor):
     c.execute(
         """ CREATE UNIQUE INDEX IF NOT EXISTS idx_repetitions_habit_timestamp 
             on Repetitions( habit, timestamp);
@@ -58,15 +58,15 @@ def create_constraints(db):
     )
 
 
-def create_pragma(db):
-    c = db.cursor()
+def create_pragma(c: sqlite3.Cursor):
     c.execute(""" PRAGMA user_version = 24; """)
     c.execute(""" PRAGMA schema_version = 30; """)
 
 
-def migrate(name):
-    db = create_database(name)
-    create_tables(db)
-    create_constraints(db)
-    create_pragma(db)
+def migrate(fname):
+    db = create_database(fname)
+    c = db.cursor()
+    create_tables(c)
+    create_constraints(c)
+    create_pragma(c)
     return db