Support python 3.14 and deprecate python 3.9

.github/workflows/ci.yml

@@ -16,39 +16,24 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python: ["3.9", "3.13"]
+        python: ["3.10", "3.14"]
         os: [ubuntu-latest, ubuntu-arm, macos-intel, macos-arm, windows-latest]
         include:
-          # On 3.9 there is a problem with import errors caused by pytests' loader that surface due
-          # to a bug in CPython (https://github.com/python/cpython/issues/91351), so we avoid using
-          # the assert rewriter.
-          - python: "3.9"
-            pytestExtraArgs: "--assert=plain"
           - os: ubuntu-latest
-            python: "3.13"
+            python: "3.14"
             docsTarget: true
             cloudTestTarget: true
             openaiTestTarget: true
             clippyLinter: true
           - os: ubuntu-latest
-            python: "3.9"
+            python: "3.10"
             protoCheckTarget: true
           - os: ubuntu-arm
             runsOn: ubuntu-24.04-arm64-2-core
           - os: macos-intel
             runsOn: macos-15-intel
-          # On 3.13.3 there is some issue with macOS intel where it hangs after pytest with some
-          # test that may have a worker that cannot properly shutdown, but it does not occur on
-          # other versions, platforms, etc. See https://github.com/temporalio/sdk-python/issues/834.
-          - os: macos-intel
-            python: "3.13"
-            pythonOverride: "3.13.2"
           - os: macos-arm
             runsOn: macos-latest
-          # On 3.13.5, python3.lib is missing for the linker
-          - os: windows-latest
-            python: "3.13"
-            pythonOverride: "3.13.4"
     runs-on: ${{ matrix.runsOn || matrix.os }}
     steps:
       - uses: actions/checkout@v4
@@ -113,7 +98,7 @@ jobs:
         env:
           TEMPORAL_TEST_PROTO3: 1
         run: |
-          uv add --python 3.9 "protobuf<4"
+          uv add --python 3.10 "protobuf<4"
           uv sync --all-extras
           poe build-develop
           poe gen-protos

pyproject.toml

@@ -3,7 +3,7 @@ name = "temporalio"
 version = "1.18.1"
 description = "Temporal.io Python SDK"
 authors = [{ name = "Temporal Technologies Inc", email = "[email protected]" }]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 readme = "README.md"
 license = { file = "LICENSE" }
 keywords = ["temporal", "workflow"]
@@ -21,8 +21,7 @@ opentelemetry = ["opentelemetry-api>=1.11.1,<2", "opentelemetry-sdk>=1.11.1,<2"]
 pydantic = ["pydantic>=2.0.0,<3"]
 openai-agents = [
   "openai-agents>=0.3,<0.4",
-  "eval-type-backport>=0.2.2; python_version < '3.10'",
-  "mcp>=1.9.4, <2; python_version >= '3.10'",
+  "mcp>=1.9.4, <2",
 ]
 
 [project.urls]
@@ -35,7 +34,7 @@ Documentation = "https://docs.temporal.io/docs/python"
 dev = [
   "cibuildwheel>=2.22.0,<3",
   "grpcio-tools>=1.48.2,<2",
-  "mypy==1.4.1",
+  "mypy==1.18.2",
   "mypy-protobuf>=3.3.0,<4",
   "psutil>=5.9.3,<6",
   "pydocstyle>=6.3.0,<7",
@@ -51,7 +50,8 @@ dev = [
   "pytest-cov>=6.1.1",
   "httpx>=0.28.1",
   "pytest-pretty>=1.3.0",
-  "openai-agents[litellm]>=0.3,<0.4",
+  "openai-agents>=0.3,<0.4; python_version >= '3.14'",
+  "openai-agents[litellm]>=0.3,<0.4; python_version < '3.14'",
   "googleapis-common-protos==1.70.0",
 ]
 
@@ -112,7 +112,7 @@ filterwarnings = [
 
 [tool.cibuildwheel]
 before-all = "pip install protoc-wheel-0"
-build = "cp39-win_amd64 cp39-manylinux_x86_64 cp39-manylinux_aarch64 cp39-macosx_x86_64 cp39-macosx_arm64"
+build = "cp310-win_amd64 cp310-manylinux_x86_64 cp310-manylinux_aarch64 cp310-macosx_x86_64 cp310-macosx_arm64"
 build-verbosity = 1
 
 [tool.cibuildwheel.macos]

temporalio/bridge/Cargo.toml

@@ -22,7 +22,7 @@ futures = "0.3"
 prost = "0.13"
 pyo3 = { version = "0.25", features = [
     "extension-module",
-    "abi3-py39",
+    "abi3-py310",
     "anyhow",
     "multiple-pymethods",
 ] }

temporalio/client.py

@@ -942,7 +942,7 @@ async def execute_update_with_start_workflow(
             MultiParamSpec, LocalReturnType
         ],
         *,
-        args: MultiParamSpec.args,  # pyright: ignore
+        args: MultiParamSpec.args,  # type: ignore
         start_workflow_operation: WithStartWorkflowOperation[SelfType, Any],
         id: Optional[str] = None,
         rpc_metadata: Mapping[str, Union[str, bytes]] = {},
@@ -1061,7 +1061,7 @@ async def start_update_with_start_workflow(
             MultiParamSpec, LocalReturnType
         ],
         *,
-        args: MultiParamSpec.args,  # pyright: ignore
+        args: MultiParamSpec.args,  # type: ignore
         start_workflow_operation: WithStartWorkflowOperation[SelfType, Any],
         wait_for_stage: WorkflowUpdateStage,
         id: Optional[str] = None,
@@ -2252,7 +2252,7 @@ async def execute_update(
             MultiParamSpec, LocalReturnType
         ],
         *,
-        args: MultiParamSpec.args,  # pyright: ignore
+        args: MultiParamSpec.args,  # type: ignore
         id: Optional[str] = None,
         rpc_metadata: Mapping[str, Union[str, bytes]] = {},
         rpc_timeout: Optional[timedelta] = None,
@@ -2353,7 +2353,7 @@ async def start_update(
             MultiParamSpec, LocalReturnType
         ],
         *,
-        args: MultiParamSpec.args,  # pyright: ignore
+        args: MultiParamSpec.args,  # type: ignore
         wait_for_stage: WorkflowUpdateStage,
         id: Optional[str] = None,
         rpc_metadata: Mapping[str, Union[str, bytes]] = {},

temporalio/contrib/openai_agents/__init__.py

@@ -8,15 +8,10 @@
     Use with caution in production environments.
 """
 
-# Best Effort mcp, as it is not supported on Python 3.9
-try:
-    from temporalio.contrib.openai_agents._mcp import (
-        StatefulMCPServerProvider,
-        StatelessMCPServerProvider,
-    )
-except ImportError:
-    pass
-
+from temporalio.contrib.openai_agents._mcp import (
+    StatefulMCPServerProvider,
+    StatelessMCPServerProvider,
+)
 from temporalio.contrib.openai_agents._model_parameters import ModelActivityParameters
 from temporalio.contrib.openai_agents._temporal_openai_agents import (
     OpenAIAgentsPlugin,

temporalio/contrib/openai_agents/_temporal_openai_agents.py

@@ -47,12 +47,6 @@
 from temporalio.worker import WorkflowRunner
 from temporalio.worker.workflow_sandbox import SandboxedWorkflowRunner
 
-# Unsupported on python 3.9
-try:
-    from agents.mcp import MCPServer
-except ImportError:
-    pass
-
 if typing.TYPE_CHECKING:
     from temporalio.contrib.openai_agents import (
         StatefulMCPServerProvider,

temporalio/worker/_workflow_instance.py

@@ -45,7 +45,7 @@
 
 import nexusrpc.handler
 from nexusrpc import InputT, OutputT
-from typing_extensions import Self, TypeAlias, TypedDict
+from typing_extensions import Self, TypeAlias, TypedDict, TypeVarTuple, Unpack
 
 import temporalio.activity
 import temporalio.api.common.v1
@@ -2603,10 +2603,12 @@ def _timer_handle_cancelled(self, handle: asyncio.TimerHandle) -> None:
             return
         handle._apply_cancel_command(self._add_command())
 
+    _Ts = TypeVarTuple("_Ts")
+
     def call_soon(
         self,
-        callback: Callable[..., Any],
-        *args: Any,
+        callback: Callable[[Unpack[_Ts]], object],
+        *args: Unpack[_Ts],
         context: Optional[contextvars.Context] = None,
     ) -> asyncio.Handle:
         # We need to allow this during delete because this is how tasks schedule
@@ -2619,8 +2621,8 @@ def call_soon(
     def call_later(
         self,
         delay: float,
-        callback: Callable[..., Any],
-        *args: Any,
+        callback: Callable[[Unpack[_Ts]], object],
+        *args: Unpack[_Ts],
         context: Optional[contextvars.Context] = None,
     ) -> asyncio.TimerHandle:
         options = _TimerOptionsCtxVar.get()
@@ -2629,8 +2631,8 @@ def call_later(
     def call_at(
         self,
         when: float,
-        callback: Callable[..., Any],
-        *args: Any,
+        callback: Callable[[Unpack[_Ts]], object],
+        *args: Unpack[_Ts],
         context: Optional[contextvars.Context] = None,
     ) -> asyncio.TimerHandle:
         # We usually would not support fixed-future-time call (and we didn't

temporalio/worker/workflow_sandbox/_importer.py

@@ -454,7 +454,7 @@ def __or__(
     ) -> Dict[str, types.ModuleType]:
         if sys.version_info < (3, 9):
             raise NotImplementedError
-        return self.current.__or__(other)
+        return self.current.__or__(other)  # type: ignore[operator]
 
     def __ior__(
         self, other: Mapping[str, types.ModuleType]

temporalio/worker/workflow_sandbox/_restrictions.py

@@ -14,6 +14,7 @@
 import math
 import operator
 import random
+import sys
 import types
 import warnings
 from copy import copy, deepcopy
@@ -646,11 +647,18 @@ def _public_callables(parent: Any, *, exclude: Set[str] = set()) -> Set[str]:
         # "linecache": SandboxMatcher.all_uses,
         # Restrict almost everything in OS at runtime
         "os": SandboxMatcher(
+            # As of https://github.com/python/cpython/pull/132662 in python 3.14 we have to allow os.path calls
+            # which may occur during exception tracing. See https://github.com/python/cpython/issues/140228.
+            children={
+                "path": SandboxMatcher.none
+                if sys.version_info >= (3, 14)
+                else SandboxMatcher.all
+            },
             access={"name"},
             use={"*"},
             # As of https://github.com/python/cpython/pull/112097, os.stat
             # calls are now made when displaying errors
-            exclude={"stat"},
+            exclude={"stat", "path"} if sys.version_info >= (3, 14) else {"stat"},
             # Only restricted at runtime
             only_runtime=True,
         ),

tests/conftest.py

@@ -64,22 +64,11 @@ def event_loop():
     try:
         loop.close()
     except TypeError:
-        # In 3.9 tests, loop closing fails for an unclear reason, but not in
-        # 3.13 tests
-        if sys.version_info >= (3, 10):
-            raise
-    finally:
-        # In 3.9 tests, the pytest-asyncio library finalizer that creates a new
-        # event loop fails, but not in 3.13 tests. So for now we will make a new
-        # policy that does not create the loop.
-        if sys.version_info < (3, 10):
-            asyncio.set_event_loop_policy(
-                NoEventLoopPolicy(asyncio.get_event_loop_policy())
-            )
-
-
-class NoEventLoopPolicy(asyncio.AbstractEventLoopPolicy):
-    def __init__(self, underlying: asyncio.AbstractEventLoopPolicy):
+        raise
+
+
+class NoEventLoopPolicy(asyncio.AbstractEventLoopPolicy):  # type: ignore[name-defined]
+    def __init__(self, underlying: asyncio.AbstractEventLoopPolicy):  # type: ignore[name-defined]
         super().__init__()
         self._underlying = underlying
 

tests/contrib/openai_agents/test_openai.py

@@ -63,6 +63,7 @@
     TResponseOutputItem,
     TResponseStreamEvent,
 )
+from agents.mcp import MCPServer, MCPServerStdio
 from openai import APIStatusError, AsyncOpenAI, BaseModel
 from openai.types.responses import (
     EasyInputMessageParam,
@@ -92,6 +93,8 @@
 from temporalio.contrib import openai_agents
 from temporalio.contrib.openai_agents import (
     ModelActivityParameters,
+    StatefulMCPServerProvider,
+    StatelessMCPServerProvider,
     TestModel,
     TestModelProvider,
 )
@@ -1769,8 +1772,8 @@ async def check():
 async def test_lite_llm(client: Client, env: WorkflowEnvironment):
     if not os.environ.get("OPENAI_API_KEY"):
         pytest.skip("No openai API key")
-    if sys.version_info < (3, 10):
-        pytest.skip("Lite LLM does not import below 3.10")
+    if sys.version_info >= (3, 14):
+        pytest.skip("Lite LLM does not yet support Python 3.14")
 
     from agents.extensions.models.litellm_provider import LitellmProvider
 
@@ -2449,9 +2452,6 @@ async def test_mcp_server(
     if not use_local_model and not os.environ.get("OPENAI_API_KEY"):
         pytest.skip("No openai API key")
 
-    if sys.version_info < (3, 10):
-        pytest.skip("Mcp not supported on Python 3.9")
-
     if stateful and caching:
         pytest.skip("Caching is only supported for stateless MCP servers")
 
@@ -2552,19 +2552,6 @@ async def test_mcp_server(
 
 @pytest.mark.parametrize("stateful", [True, False])
 async def test_mcp_server_factory_argument(client: Client, stateful: bool):
-    if sys.version_info < (3, 10):
-        pytest.skip("Mcp not supported on Python 3.9")
-
-    from agents.mcp import MCPServer  # type: ignore
-    from mcp import GetPromptResult, ListPromptsResult  # type: ignore
-    from mcp import Tool as MCPTool  # type: ignore
-    from mcp.types import CallToolResult, TextContent  # type: ignore
-
-    from temporalio.contrib.openai_agents import (
-        StatefulMCPServerProvider,
-        StatelessMCPServerProvider,
-    )
-
     def factory(args: Optional[Any]) -> MCPServer:
         print("Invoking factory: ", args)
         if args is not None:
@@ -2614,12 +2601,6 @@ def factory(args: Optional[Any]) -> MCPServer:
 
 
 async def test_stateful_mcp_server_no_worker(client: Client):
-    if sys.version_info < (3, 10):
-        pytest.skip("Mcp not supported on Python 3.9")
-    from agents.mcp import MCPServerStdio
-
-    from temporalio.contrib.openai_agents import StatefulMCPServerProvider
-
     server = StatefulMCPServerProvider(
         "Filesystem-Server",
         lambda _: MCPServerStdio(

tests/contrib/test_opentelemetry.py

@@ -8,6 +8,7 @@
 from datetime import timedelta
 from typing import Iterable, List, Optional
 
+import pytest
 from opentelemetry.sdk.trace import ReadableSpan, TracerProvider
 from opentelemetry.sdk.trace.export import SimpleSpanProcessor
 from opentelemetry.sdk.trace.export.in_memory_span_exporter import InMemorySpanExporter
@@ -22,11 +23,6 @@
 from temporalio.testing import WorkflowEnvironment
 from temporalio.worker import UnsandboxedWorkflowRunner, Worker
 
-# Passing through because Python 3.9 has an import bug at
-# https://github.com/python/cpython/issues/91351
-with workflow.unsafe.imports_passed_through():
-    import pytest
-
 
 @dataclass
 class TracingActivityParam:

tests/test_client.py

@@ -7,6 +7,7 @@
 from unittest import mock
 
 import google.protobuf.any_pb2
+import pytest
 from google.protobuf import json_format
 
 import temporalio.api.common.v1
@@ -101,11 +102,6 @@
     KSWorkflowParams,
 )
 
-# Passing through because Python 3.9 has an import bug at
-# https://github.com/python/cpython/issues/91351
-with workflow.unsafe.imports_passed_through():
-    import pytest
-
 
 async def test_start_id_reuse(
     client: Client, worker: ExternalWorker, env: WorkflowEnvironment