diff --git a/dandi/cli/tests/test_cmd_ls.py b/dandi/cli/tests/test_cmd_ls.py
index 68b299d28..e8468895e 100644
--- a/dandi/cli/tests/test_cmd_ls.py
+++ b/dandi/cli/tests/test_cmd_ls.py
@@ -11,7 +11,7 @@
 
 from dandi.tests.skip import mark
 
-from ..ls import ls
+from ..cmd_ls import ls
 from ...utils import yaml_load
 
 
diff --git a/dandi/cli/tests/test_command.py b/dandi/cli/tests/test_command.py
index 4b95ac8c8..e03e4e926 100644
--- a/dandi/cli/tests/test_command.py
+++ b/dandi/cli/tests/test_command.py
@@ -6,9 +6,9 @@
 from click.testing import CliRunner
 import pytest
 
+from ..cmd_ls import ls
+from ..cmd_validate import validate
 from ..command import __all_commands__
-from ..ls import ls
-from ..validate import validate
 
 
 @pytest.mark.parametrize("command", (ls, validate))
diff --git a/dandi/cli/tests/test_download.py b/dandi/cli/tests/test_download.py
index c1b50025d..164860c46 100644
--- a/dandi/cli/tests/test_download.py
+++ b/dandi/cli/tests/test_download.py
@@ -5,7 +5,7 @@
 from click.testing import CliRunner
 import pytest
 
-from ..download import download
+from ..cmd_download import download
 from ...consts import dandiset_metadata_file, known_instances
 
 
diff --git a/dandi/cli/tests/test_instances.py b/dandi/cli/tests/test_instances.py
index 06d45b46c..4e058db28 100644
--- a/dandi/cli/tests/test_instances.py
+++ b/dandi/cli/tests/test_instances.py
@@ -2,7 +2,7 @@
 
 from click.testing import CliRunner
 
-from ..instances import instances
+from ..cmd_instances import instances
 
 
 def test_cmd_instances(monkeypatch):
diff --git a/dandi/cli/tests/test_move.py b/dandi/cli/tests/test_move.py
index 6242ab484..9eca9545a 100644
--- a/dandi/cli/tests/test_move.py
+++ b/dandi/cli/tests/test_move.py
@@ -7,7 +7,7 @@
 import pytest
 from pytest_mock import MockerFixture
 
-from ..move import move
+from ..cmd_move import move
 
 
 @pytest.mark.parametrize(
diff --git a/dandi/cli/tests/test_service_scripts.py b/dandi/cli/tests/test_service_scripts.py
index da8c59ce8..852261c91 100644
--- a/dandi/cli/tests/test_service_scripts.py
+++ b/dandi/cli/tests/test_service_scripts.py
@@ -16,7 +16,7 @@
 from dandi import __version__
 from dandi.tests.fixtures import SampleDandiset
 
-from ..service_scripts import service_scripts
+from ..cmd_service_scripts import service_scripts
 
 DATA_DIR = Path(__file__).with_name("data")
 
diff --git a/dandi/consts.py b/dandi/consts.py
index d8e47350d..23964483f 100644
--- a/dandi/consts.py
+++ b/dandi/consts.py
@@ -4,6 +4,7 @@
 from dataclasses import dataclass
 from enum import Enum
 import os
+from typing import Union
 
 #: A list of metadata fields which dandi extracts from .nwb files.
 #: Additional fields (such as ``number_of_*``) might be added by
@@ -98,7 +99,9 @@ class EmbargoStatus(Enum):
 @dataclass(frozen=True)
 class DandiInstance:
     name: str
-    gui: str | None
+    # This class is used as an attribute of ParsedDandiURL, a Pydantic class,
+    # and thus we need non-future annotations:
+    gui: Union[str, None]
     api: str
 
     @property
diff --git a/dandi/dandiapi.py b/dandi/dandiapi.py
index c0f86a064..4c2ad220c 100644
--- a/dandi/dandiapi.py
+++ b/dandi/dandiapi.py
@@ -13,7 +13,7 @@
 import re
 from time import sleep, time
 from types import TracebackType
-from typing import TYPE_CHECKING, Any, ClassVar, Dict, List, Optional
+from typing import TYPE_CHECKING, Any, ClassVar, Dict, FrozenSet, List, Optional
 from urllib.parse import quote_plus, urlparse, urlunparse
 
 import click
@@ -621,7 +621,7 @@ class APIBase(BaseModel):
     detail; do not rely on it.
     """
 
-    JSON_EXCLUDE: ClassVar[frozenset[str]] = frozenset(["client"])
+    JSON_EXCLUDE: ClassVar[FrozenSet[str]] = frozenset(["client"])
 
     def json_dict(self) -> dict[str, Any]:
         """
diff --git a/dandi/dandiarchive.py b/dandi/dandiarchive.py
index 3bed6549e..fd4736da9 100644
--- a/dandi/dandiarchive.py
+++ b/dandi/dandiarchive.py
@@ -33,7 +33,7 @@
 import posixpath
 import re
 from time import sleep
-from typing import Any
+from typing import Any, Union
 from urllib.parse import unquote as urlunquote
 
 from pydantic import AnyHttpUrl, BaseModel, parse_obj_as
@@ -70,11 +70,11 @@ class ParsedDandiURL(ABC, BaseModel):
     #: The Dandi Archive instance that the URL points to
     instance: DandiInstance
     #: The ID of the Dandiset given in the URL
-    dandiset_id: str | None
+    dandiset_id: Union[str, None]
     #: The version of the Dandiset, if specified.  If this is not set, the
     #: version will be defaulted using the rules described under
     #: `DandiAPIClient.get_dandiset()`.
-    version_id: str | None = None
+    version_id: Union[str, None] = None
 
     @property
     def api_url(self) -> AnyHttpUrl:
diff --git a/dandi/tests/fixtures.py b/dandi/tests/fixtures.py
index 4c3b355e8..84d9fa74b 100644
--- a/dandi/tests/fixtures.py
+++ b/dandi/tests/fixtures.py
@@ -30,7 +30,7 @@
 
 from .skip import skipif
 from .. import get_logger
-from ..cli.organize import organize
+from ..cli.cmd_organize import organize
 from ..consts import (
     DandiInstance,
     dandiset_metadata_file,
diff --git a/dandi/tests/test_organize.py b/dandi/tests/test_organize.py
index 01c2994f0..224d7605e 100644
--- a/dandi/tests/test_organize.py
+++ b/dandi/tests/test_organize.py
@@ -10,7 +10,7 @@
 import pytest
 import ruamel.yaml
 
-from ..cli.organize import organize
+from ..cli.cmd_organize import organize
 from ..consts import dandiset_metadata_file, file_operation_modes
 from ..organize import (
     _sanitize_value,