diff --git a/pyproject.toml b/pyproject.toml
index 116a646276..574b09b076 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -153,7 +153,7 @@ run-coverage-gpu = "pip install cupy-cuda12x && pytest -m gpu --cov-config=pypro
 run = "run-coverage --no-cov"
 run-verbose = "run-coverage --verbose"
 run-mypy = "mypy src"
-run-hypothesis = "pytest --hypothesis-profile ci tests/v3/test_properties.py tests/v3/test_store/test_stateful*"
+run-hypothesis = "pytest --hypothesis-profile ci tests/test_properties.py tests/test_store/test_stateful*"
 list-env = "pip list"
 
 [tool.hatch.envs.gputest]
@@ -173,7 +173,7 @@ run-coverage = "pytest -m gpu --cov-config=pyproject.toml --cov=pkg --cov=tests"
 run = "run-coverage --no-cov"
 run-verbose = "run-coverage --verbose"
 run-mypy = "mypy src"
-run-hypothesis = "pytest --hypothesis-profile ci tests/v3/test_properties.py tests/v3/test_store/test_stateful*"
+run-hypothesis = "pytest --hypothesis-profile ci tests/test_properties.py tests/test_store/test_stateful*"
 list-env = "pip list"
 
 [tool.hatch.envs.docs]
@@ -282,18 +282,17 @@ ignore_errors = true
 
 [[tool.mypy.overrides]]
 module = [
-    "tests.v2.*",
-    "tests.v3.package_with_entrypoint.*",
-    "tests.v3.test_codecs.test_codecs",
-    "tests.v3.test_codecs.test_transpose",
-    "tests.v3.test_metadata.*",
-    "tests.v3.test_store.*",
-    "tests.v3.test_config",
-    "tests.v3.test_group",
-    "tests.v3.test_indexing",
-    "tests.v3.test_properties",
-    "tests.v3.test_sync",
-    "tests.v3.test_v2",
+    "tests.package_with_entrypoint.*",
+    "tests.test_codecs.test_codecs",
+    "tests.test_codecs.test_transpose",
+    "tests.test_metadata.*",
+    "tests.test_store.*",
+    "tests.test_config",
+    "tests.test_group",
+    "tests.test_indexing",
+    "tests.test_properties",
+    "tests.test_sync",
+    "tests.test_v2",
 ]
 ignore_errors = true
 
diff --git a/src/zarr/testing/utils.py b/src/zarr/testing/utils.py
index 9d6dfa7e18..c7b6e7939c 100644
--- a/src/zarr/testing/utils.py
+++ b/src/zarr/testing/utils.py
@@ -1,6 +1,7 @@
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Any, cast
+from collections.abc import Callable, Coroutine
+from typing import TYPE_CHECKING, Any, TypeVar, cast
 
 import pytest
 
@@ -37,8 +38,16 @@ def has_cupy() -> bool:
         return False
 
 
+T_Callable = TypeVar("T_Callable", bound=Callable[[], Coroutine[Any, Any, None]])
+
+
 # Decorator for GPU tests
-def gpu_test(func: Any) -> Any:
-    return pytest.mark.gpu(
-        pytest.mark.skipif(not has_cupy(), reason="CuPy not installed or no GPU available")(func)
+def gpu_test(func: T_Callable) -> T_Callable:
+    return cast(
+        T_Callable,
+        pytest.mark.gpu(
+            pytest.mark.skipif(not has_cupy(), reason="CuPy not installed or no GPU available")(
+                func
+            )
+        ),
     )
diff --git a/tests/v3/conftest.py b/tests/conftest.py
similarity index 100%
rename from tests/v3/conftest.py
rename to tests/conftest.py
diff --git a/tests/v3/package_with_entrypoint-0.1.dist-info/entry_points.txt b/tests/package_with_entrypoint-0.1.dist-info/entry_points.txt
similarity index 100%
rename from tests/v3/package_with_entrypoint-0.1.dist-info/entry_points.txt
rename to tests/package_with_entrypoint-0.1.dist-info/entry_points.txt
diff --git a/tests/v3/package_with_entrypoint/__init__.py b/tests/package_with_entrypoint/__init__.py
similarity index 100%
rename from tests/v3/package_with_entrypoint/__init__.py
rename to tests/package_with_entrypoint/__init__.py
diff --git a/tests/v3/test_api.py b/tests/test_api.py
similarity index 100%
rename from tests/v3/test_api.py
rename to tests/test_api.py
diff --git a/tests/v3/test_array.py b/tests/test_array.py
similarity index 100%
rename from tests/v3/test_array.py
rename to tests/test_array.py
diff --git a/tests/v3/test_attributes.py b/tests/test_attributes.py
similarity index 100%
rename from tests/v3/test_attributes.py
rename to tests/test_attributes.py
diff --git a/tests/v3/test_buffer.py b/tests/test_buffer.py
similarity index 100%
rename from tests/v3/test_buffer.py
rename to tests/test_buffer.py
diff --git a/tests/v3/test_chunk_grids.py b/tests/test_chunk_grids.py
similarity index 100%
rename from tests/v3/test_chunk_grids.py
rename to tests/test_chunk_grids.py
diff --git a/tests/v3/test_codec_entrypoints.py b/tests/test_codec_entrypoints.py
similarity index 100%
rename from tests/v3/test_codec_entrypoints.py
rename to tests/test_codec_entrypoints.py
diff --git a/tests/v3/__init__.py b/tests/test_codecs/__init__.py
similarity index 100%
rename from tests/v3/__init__.py
rename to tests/test_codecs/__init__.py
diff --git a/tests/v3/test_codecs/test_blosc.py b/tests/test_codecs/test_blosc.py
similarity index 100%
rename from tests/v3/test_codecs/test_blosc.py
rename to tests/test_codecs/test_blosc.py
diff --git a/tests/v3/test_codecs/test_codecs.py b/tests/test_codecs/test_codecs.py
similarity index 100%
rename from tests/v3/test_codecs/test_codecs.py
rename to tests/test_codecs/test_codecs.py
diff --git a/tests/v3/test_codecs/test_endian.py b/tests/test_codecs/test_endian.py
similarity index 100%
rename from tests/v3/test_codecs/test_endian.py
rename to tests/test_codecs/test_endian.py
diff --git a/tests/v3/test_codecs/test_gzip.py b/tests/test_codecs/test_gzip.py
similarity index 100%
rename from tests/v3/test_codecs/test_gzip.py
rename to tests/test_codecs/test_gzip.py
diff --git a/tests/v3/test_codecs/test_sharding.py b/tests/test_codecs/test_sharding.py
similarity index 100%
rename from tests/v3/test_codecs/test_sharding.py
rename to tests/test_codecs/test_sharding.py
diff --git a/tests/v3/test_codecs/test_transpose.py b/tests/test_codecs/test_transpose.py
similarity index 100%
rename from tests/v3/test_codecs/test_transpose.py
rename to tests/test_codecs/test_transpose.py
diff --git a/tests/v3/test_codecs/test_vlen.py b/tests/test_codecs/test_vlen.py
similarity index 100%
rename from tests/v3/test_codecs/test_vlen.py
rename to tests/test_codecs/test_vlen.py
diff --git a/tests/v3/test_codecs/test_zstd.py b/tests/test_codecs/test_zstd.py
similarity index 100%
rename from tests/v3/test_codecs/test_zstd.py
rename to tests/test_codecs/test_zstd.py
diff --git a/tests/v3/test_common.py b/tests/test_common.py
similarity index 100%
rename from tests/v3/test_common.py
rename to tests/test_common.py
diff --git a/tests/v3/test_config.py b/tests/test_config.py
similarity index 98%
rename from tests/v3/test_config.py
rename to tests/test_config.py
index 62907588c7..c4cf794c5f 100644
--- a/tests/v3/test_config.py
+++ b/tests/test_config.py
@@ -87,7 +87,7 @@ class MockClass:
 
     assert (
         fully_qualified_name(MockClass)
-        == "tests.v3.test_config.test_fully_qualified_name.<locals>.MockClass"
+        == "tests.test_config.test_fully_qualified_name.<locals>.MockClass"
     )
 
 
diff --git a/tests/v3/test_group.py b/tests/test_group.py
similarity index 100%
rename from tests/v3/test_group.py
rename to tests/test_group.py
diff --git a/tests/v3/test_indexing.py b/tests/test_indexing.py
similarity index 100%
rename from tests/v3/test_indexing.py
rename to tests/test_indexing.py
diff --git a/tests/v3/test_codecs/__init__.py b/tests/test_metadata/__init__.py
similarity index 100%
rename from tests/v3/test_codecs/__init__.py
rename to tests/test_metadata/__init__.py
diff --git a/tests/v3/test_metadata/test_consolidated.py b/tests/test_metadata/test_consolidated.py
similarity index 100%
rename from tests/v3/test_metadata/test_consolidated.py
rename to tests/test_metadata/test_consolidated.py
diff --git a/tests/v3/test_metadata/test_v2.py b/tests/test_metadata/test_v2.py
similarity index 100%
rename from tests/v3/test_metadata/test_v2.py
rename to tests/test_metadata/test_v2.py
diff --git a/tests/v3/test_metadata/test_v3.py b/tests/test_metadata/test_v3.py
similarity index 100%
rename from tests/v3/test_metadata/test_v3.py
rename to tests/test_metadata/test_v3.py
diff --git a/tests/v3/test_properties.py b/tests/test_properties.py
similarity index 100%
rename from tests/v3/test_properties.py
rename to tests/test_properties.py
diff --git a/tests/v3/test_metadata/__init__.py b/tests/test_store/__init__.py
similarity index 100%
rename from tests/v3/test_metadata/__init__.py
rename to tests/test_store/__init__.py
diff --git a/tests/v3/test_store/test_core.py b/tests/test_store/test_core.py
similarity index 100%
rename from tests/v3/test_store/test_core.py
rename to tests/test_store/test_core.py
diff --git a/tests/v3/test_store/test_local.py b/tests/test_store/test_local.py
similarity index 100%
rename from tests/v3/test_store/test_local.py
rename to tests/test_store/test_local.py
diff --git a/tests/v3/test_store/test_logging.py b/tests/test_store/test_logging.py
similarity index 100%
rename from tests/v3/test_store/test_logging.py
rename to tests/test_store/test_logging.py
diff --git a/tests/v3/test_store/test_memory.py b/tests/test_store/test_memory.py
similarity index 100%
rename from tests/v3/test_store/test_memory.py
rename to tests/test_store/test_memory.py
diff --git a/tests/v3/test_store/test_remote.py b/tests/test_store/test_remote.py
similarity index 100%
rename from tests/v3/test_store/test_remote.py
rename to tests/test_store/test_remote.py
diff --git a/tests/v3/test_store/test_stateful_store.py b/tests/test_store/test_stateful_store.py
similarity index 100%
rename from tests/v3/test_store/test_stateful_store.py
rename to tests/test_store/test_stateful_store.py
diff --git a/tests/v3/test_store/test_zip.py b/tests/test_store/test_zip.py
similarity index 100%
rename from tests/v3/test_store/test_zip.py
rename to tests/test_store/test_zip.py
diff --git a/tests/v3/test_sync.py b/tests/test_sync.py
similarity index 100%
rename from tests/v3/test_sync.py
rename to tests/test_sync.py
diff --git a/tests/v3/test_v2.py b/tests/test_v2.py
similarity index 100%
rename from tests/v3/test_v2.py
rename to tests/test_v2.py
diff --git a/tests/v3/test_store/__init__.py b/tests/v3/test_store/__init__.py
deleted file mode 100644
index e69de29bb2..0000000000