Netflix · agsaru · Jun 10, 2026 · Jun 11, 2026
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
@@ -43,11 +43,10 @@ repos:
         files: ^devtools/ci/
         args: [-e, SC1091]  # don't follow sourced files
 
-  - repo: https://github.com/ambv/black
-    rev: 25.12.0
+  - repo: https://github.com/psf/black
+    rev: 26.5.1
     hooks:
       - id: black
         language_version: python3
         exclude: "^metaflow/_vendor/"
-        additional_dependencies: ["click<8.1.0"]
-        args: [-t, py34, -t, py35, -t, py36, -t, py37, -t, py38, -t, py39, -t, py310, -t, py311, -t, py312, -t, py313, -t, py314]
+        args: [-t, py34, -t, py35, -t, py36, -t, py37, -t, py38, -t, py39, -t, py310, -t, py311, -t, py312, -t, py313, -t, py314, -t, py315]
diff --git a/metaflow/__init__.py b/metaflow/__init__.py
@@ -125,7 +125,6 @@ class and related decorators.
 # Decorators
 from .decorators import step, _import_plugin_decorators
 
-
 # Parsers (for configs) for now
 from .plugins import _import_tl_plugins
 

diff --git a/metaflow/cmd/configure_cmd.py b/metaflow/cmd/configure_cmd.py
@@ -11,7 +11,6 @@
 
 from .util import echo_always, makedirs
 
-
 echo = echo_always
 
 # NOTE: This code needs to be in sync with metaflow/metaflow_config.py.

diff --git a/metaflow/cmd/develop/stubs.py b/metaflow/cmd/develop/stubs.py
@@ -155,8 +155,7 @@ def install(ctx: Any, force: bool):
     mf_version, _ = get_mf_version(True)
     with tempfile.TemporaryDirectory() as tmp_dir:
         with open(os.path.join(tmp_dir, "setup.py"), "w") as f:
-            f.write(
-                f"""
+            f.write(f"""
 from setuptools import setup, find_namespace_packages
 setup(
     include_package_data=True,
@@ -171,16 +170,13 @@ def install(ctx: Any, force: bool):
     install_requires=["metaflow=={mf_version}"],
     python_requires=">=3.6.1",
 )
-                """
-            )
+                """)
         with open(os.path.join(tmp_dir, "MANIFEST.in"), "w") as f:
-            f.write(
-                """
+            f.write("""
 include metaflow-stubs/generated_for.txt
 include metaflow-stubs/py.typed
 global-include *.pyi
-                """
-            )
+                """)
 
         StubGenerator(os.path.join(tmp_dir, "metaflow-stubs")).write_out()
 

diff --git a/metaflow/extension_support/__init__.py b/metaflow/extension_support/__init__.py
@@ -16,7 +16,6 @@
 from metaflow.meta_files import read_info_file
 from metaflow.util import walk_without_cycles
 
-
 #
 # This file provides the support for Metaflow's extension mechanism which allows
 # a Metaflow developer to extend metaflow by providing a package `metaflow_extensions`.

diff --git a/metaflow/plugins/airflow/airflow_utils.py b/metaflow/plugins/airflow/airflow_utils.py
@@ -5,7 +5,6 @@
 from collections import defaultdict
 from datetime import datetime, timedelta
 
-
 TASK_ID_XCOM_KEY = "metaflow_task_id"
 FOREACH_CARDINALITY_XCOM_KEY = "metaflow_foreach_cardinality"
 FOREACH_XCOM_KEY = "metaflow_foreach_indexes"

diff --git a/metaflow/plugins/airflow/sensors/external_task_sensor.py b/metaflow/plugins/airflow/sensors/external_task_sensor.py
@@ -3,7 +3,6 @@
 from ..exception import AirflowException
 from datetime import timedelta
 
-
 AIRFLOW_STATES = dict(
     QUEUED="queued",
     RUNNING="running",

diff --git a/metaflow/plugins/cards/card_creator.py b/metaflow/plugins/cards/card_creator.py
@@ -7,7 +7,6 @@
 from metaflow import current
 from typing import Callable, Tuple, Dict
 
-
 ASYNC_TIMEOUT = 30
 
 

diff --git a/metaflow/plugins/datastores/azure_storage.py b/metaflow/plugins/datastores/azure_storage.py
@@ -25,7 +25,6 @@
     get_azure_blob_service_client,
 )
 
-
 # How many threads / connections to use per upload or download operation
 from metaflow.plugins.storage_executor import (
     StorageExecutor,

diff --git a/metaflow/plugins/datastores/s3_storage.py b/metaflow/plugins/datastores/s3_storage.py
@@ -6,7 +6,6 @@
 from metaflow.metaflow_config import DATASTORE_SYSROOT_S3, ARTIFACT_LOCALROOT
 from metaflow.datastore.datastore_storage import CloseAfterUse, DataStoreStorage
 
-
 try:
     # python2
     from urlparse import urlparse

diff --git a/metaflow/plugins/datatools/s3/s3util.py b/metaflow/plugins/datatools/s3/s3util.py
@@ -13,7 +13,6 @@
     RETRY_WARNING_THRESHOLD,
 )
 
-
 TEST_S3_RETRY = "TEST_S3_RETRY" in os.environ
 
 TRANSIENT_RETRY_LINE_CONTENT = "<none>"

diff --git a/metaflow/runner/click_api.py b/metaflow/runner/click_api.py
@@ -8,11 +8,9 @@
 elif _py_ver >= (3, 7):
     from metaflow._vendor.v3_7.typeguard import TypeCheckError, check_type
 else:
-    raise RuntimeError(
-        """
+    raise RuntimeError("""
         The Metaflow Programmatic API is not supported for versions of Python less than 3.7
-    """
-    )
+    """)
 
 import functools
 import importlib

diff --git a/metaflow/sidecar/sidecar_worker.py b/metaflow/sidecar/sidecar_worker.py
@@ -5,7 +5,6 @@
 
 import traceback
 
-
 # add metaflow module to python path if not already present
 myDir = os.path.dirname(os.path.abspath(__file__))
 parentDir = os.path.split(os.path.split(myDir)[0])[0]

diff --git a/metaflow/user_configs/config_options.py b/metaflow/user_configs/config_options.py
@@ -13,7 +13,6 @@
 from ..parameters import DeployTimeField, ParameterContext, current_flow
 from ..util import get_username
 
-
 _CONVERT_PREFIX = "@!c!@:"
 _DEFAULT_PREFIX = "@!d!@:"
 _NO_FILE = "@!n!@:"

diff --git a/test/core/tests/secrets_decorator.py b/test/core/tests/secrets_decorator.py
@@ -1,6 +1,5 @@
 from metaflow_test import MetaflowTest, ExpectationFailed, steps, tag
 
-
 INLINE_SECRETS_VARS = [
     {
         "type": "inline",

diff --git a/test/plugins/conda/test_parsers.py b/test/plugins/conda/test_parsers.py
@@ -12,7 +12,6 @@
     requirements_txt_parser,
 )
 
-
 # ---------------------------------------------------------------------------
 # requirements_txt_parser
 # ---------------------------------------------------------------------------

diff --git a/test/unit/graph_inference/test_graph_inference.py b/test/unit/graph_inference/test_graph_inference.py
@@ -11,7 +11,6 @@
 
 from metaflow.events import Trigger
 
-
 # ---------------------------------------------------------------------------
 # Custom named flow (begin/middle/finish)
 # ---------------------------------------------------------------------------

diff --git a/test/unit/test_add_to_package.py b/test/unit/test_add_to_package.py
@@ -19,7 +19,6 @@
 )
 from metaflow.packaging_sys import ContentType
 
-
 # ---------------------------------------------------------------------------
 # Helpers
 # ---------------------------------------------------------------------------

diff --git a/test/unit/test_artifact_serializer.py b/test/unit/test_artifact_serializer.py
@@ -8,7 +8,6 @@
     SerializerStore,
 )
 
-
 # Snapshot the registry before this module's classes are defined. Module-level
 # test serializers (_HighPrioritySerializer, ...) self-register at class
 # definition time; the module-scoped fixture below removes them at teardown so

diff --git a/test/unit/test_compute_resource_attributes.py b/test/unit/test_compute_resource_attributes.py
@@ -1,7 +1,6 @@
 from collections import namedtuple
 from metaflow.plugins.aws.aws_utils import compute_resource_attributes
 
-
 MockDeco = namedtuple("MockDeco", ["name", "attributes"])
 
 

diff --git a/test/unit/test_pickle_serializer.py b/test/unit/test_pickle_serializer.py
@@ -8,7 +8,6 @@
 )
 from metaflow.plugins.datastores.serializers.pickle_serializer import PickleSerializer
 
-
 # ---------------------------------------------------------------------------
 # Registration and identity
 # ---------------------------------------------------------------------------

diff --git a/test/ux/core/test_compliance.py b/test/ux/core/test_compliance.py
@@ -23,7 +23,6 @@
     wait_for_deployed_run_allow_failure,
 )
 
-
 # ---------------------------------------------------------------------------
 # test_run_params_multiple_values
 #

diff --git a/test/ux/core/test_utils.py b/test/ux/core/test_utils.py
@@ -5,7 +5,6 @@
 from metaflow import Deployer, Flow, Run, Runner, namespace
 from metaflow.exception import MetaflowNotFound
 
-
 # Directory containing the test flows, relative to this file
 _FLOWS_DIR = os.path.join(os.path.dirname(__file__), "flows")
Original file line number	Diff line number	Diff line change
Expand Up		@@ -11,7 +11,6 @@

		from .util import echo_always, makedirs


		echo = echo_always

		# NOTE: This code needs to be in sync with metaflow/metaflow_config.py.
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -7,7 +7,6 @@
		from metaflow import current
		from typing import Callable, Tuple, Dict


		ASYNC_TIMEOUT = 30


Expand Down
-Original file line number
+Diff line change
@@ Expand Up / @@ -13,7 +13,6 @@ @@
         RETRY_WARNING_THRESHOLD,
     )
     TEST_S3_RETRY = "TEST_S3_RETRY" in os.environ
     TRANSIENT_RETRY_LINE_CONTENT = "<none>"
@@ Expand Down @@