diff --git a/keyosk/config/__init__.py b/keyosk/config/__init__.py
index 9b5f92f..03a3aa2 100644
--- a/keyosk/config/__init__.py
+++ b/keyosk/config/__init__.py
@@ -13,6 +13,7 @@ import toml
 
 from keyosk import constants
 from keyosk.config.storage import KeyoskStorageConfig
+from keyosk.config.storage import StorageBackend  # pylint: disable=unused-import
 from keyosk.config.storage import StorageConfigSerializer
 
 
diff --git a/keyosk/config/storage.py b/keyosk/config/storage.py
index 8fdb118..d26a7b9 100644
--- a/keyosk/config/storage.py
+++ b/keyosk/config/storage.py
@@ -1,4 +1,5 @@
 """Data containers and utilities related to the storage configuration"""
+import enum
 from dataclasses import asdict
 from dataclasses import dataclass
 from dataclasses import field
@@ -11,10 +12,17 @@ from typing import Union
 
 import marshmallow as msh
 
-from keyosk import datatypes
 from keyosk import fields as custom_fields
 
 
+@enum.unique
+class StorageBackend(enum.Enum):
+    """Supported storage backends"""
+
+    SQLITE = "sqlite"
+    MARIA = "maria"
+
+
 def _default_sqlite_pragmas() -> Dict[str, Any]:
     """Generate the default pragmas for the sqlite connection
 
@@ -131,7 +139,7 @@ class KeyoskStorageConfig:
               time, depending on the value of the ``backend`` setting.
     """
 
-    backend: datatypes.StorageBackend = datatypes.StorageBackend.SQLITE
+    backend: StorageBackend = StorageBackend.SQLITE
     sqlite: KeyoskSQLiteStorageConfig = KeyoskSQLiteStorageConfig()
     maria: KeyoskMariaStorageConfig = KeyoskMariaStorageConfig()
 
@@ -143,7 +151,7 @@ class StorageConfigSerializer(msh.Schema):
     :class:`KeyoskStorageConfig` class.
     """
 
-    backend = custom_fields.EnumItem(datatypes.StorageBackend, pretty_names=True)
+    backend = custom_fields.EnumItem(StorageBackend, pretty_names=True)
     sqlite = msh.fields.Nested(SQLiteStorageConfigSerializer)
     maria = msh.fields.Nested(MariaStorageConfigSerializer)
 
diff --git a/keyosk/database/__init__.py b/keyosk/database/__init__.py
index c648750..fb75f82 100644
--- a/keyosk/database/__init__.py
+++ b/keyosk/database/__init__.py
@@ -24,7 +24,6 @@ from typing import Type
 import peewee
 
 from keyosk import config
-from keyosk import datatypes
 from keyosk.database._shared import INTERFACE as interface
 from keyosk.database._shared import KeyoskBaseModel
 from keyosk.database.account import Account
@@ -57,7 +56,7 @@ def initialize(conf: config.KeyoskConfig):
 
     logger = logging.getLogger(__name__)
 
-    if conf.storage.backend == datatypes.StorageBackend.SQLITE:
+    if conf.storage.backend == config.StorageBackend.SQLITE:
         logger.debug("Using SQLite database backend")
         logger.debug(f"Applying SQLite pragmas: {conf.storage.sqlite.pragmas}")
         # Explicit cast-to-string on the path is to support py3.6: sqlite driver
@@ -66,7 +65,7 @@ def initialize(conf: config.KeyoskConfig):
             str(conf.storage.sqlite.path), pragmas=conf.storage.sqlite.pragmas
         )
 
-    elif conf.storage.backend == datatypes.StorageBackend.MARIA:
+    elif conf.storage.backend == config.StorageBackend.MARIA:
         logger.debug("Using MariaDB database backend")
         logger.debug(
             f"Configuring MariaDB: {conf.storage.maria.username}@{conf.storage.maria.host}:{conf.storage.maria.port}, with database '{conf.storage.maria.schema}'"
diff --git a/keyosk/datatypes.py b/keyosk/datatypes.py
deleted file mode 100644
index 088b4e6..0000000
--- a/keyosk/datatypes.py
+++ /dev/null
@@ -1,18 +0,0 @@
-"""Shared types, enums, and data containers"""
-import enum
-from typing import Dict
-from typing import Union
-
-
-Extras = Dict[str, Union[int, float, bool, str, None]]
-
-
-TokenClaims = Dict[str, Union[str, int, bool, Dict[str, int]]]
-
-
-@enum.unique
-class StorageBackend(enum.Enum):
-    """Supported storage backends"""
-
-    SQLITE = "sqlite"
-    MARIA = "maria"
diff --git a/keyosk/datatypes/__init__.py b/keyosk/datatypes/__init__.py
new file mode 100644
index 0000000..86dcbe0
--- /dev/null
+++ b/keyosk/datatypes/__init__.py
@@ -0,0 +1,8 @@
+from typing import Dict
+from typing import Union
+
+
+Extras = Dict[str, Union[int, float, bool, str, None]]
+
+
+TokenClaims = Dict[str, Union[str, int, bool, Dict[str, int]]]
diff --git a/tests/test_config.py b/tests/test_config.py
index c4fb69b..52ba773 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -5,7 +5,6 @@ import toml
 
 from keyosk import config
 from keyosk import constants
-from keyosk import datatypes
 
 
 DEMO_CONFIG = {
@@ -39,7 +38,7 @@ def test_roundtrip():
 
 def test_settings():
     loaded = config.ConfigSerializer().load(DEMO_CONFIG)
-    assert loaded.storage.backend == datatypes.StorageBackend.MARIA
+    assert loaded.storage.backend == config.StorageBackend.MARIA
     assert loaded.storage.sqlite.path == Path(DEMO_CONFIG["storage"]["sqlite"]["path"])
     assert loaded.storage.sqlite.pragmas == DEMO_CONFIG["storage"]["sqlite"]["pragmas"]
     for key, value in DEMO_CONFIG["storage"]["maria"].items():
diff --git a/tox.ini b/tox.ini
index 53669fd..1070af0 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py37, py36, lint, typing, security, docs
+envlist = py36, py37, py38, lint, typing, security, docs
 isolated_build = true
 
 [testenv]