chore!: drop Python 3.10 support, add Python 3.15

[julian-risch]

Related Issues

• fixes Drop Python 3.10 support and add Python 3.15 #13065

Proposed Changes:

Python 3.10 reaches end of life in October 2026, and Python 3.15.0 was released on 2026-10-09.

• Python versions: requires-python is now >=3.11. The 3.10 classifier is replaced by a 3.15 classifier. All workflows that used 3.10 as the base version now use 3.11.
• Dropped typing_extensions: NotRequired and Self now come from typing. The license-compliance exclusion that only existed for typing_extensions is removed.
• 3.11+ idioms: tests use datetime.UTC instead of timezone.utc. Comments that described 3.10-only behavior in type_utils.py and filters.py are rewritten.
• Enums: ChatRole and ConverterMimeType stay class X(str, Enum), marked # noqa: UP042. Switching to StrEnum would change str() of the members. That is user-visible for ChatRole, and MultiFileConverter.__init__() parses it to name its internal components.
• Type serialization tests: expectations are gated on sys.version_info >= (3, 14), because from 3.14 on typing.Union/Optional serialize with PEP 604 syntax (str | None).
• Async pipeline feature tests: six scenarios in test/core/pipeline/features/test_run.py now compare variadic inputs with AnyOrder.
  • Pipeline.run_async() writes a component's outputs when its thread finishes, so a variadic socket receives inputs in completion order.
  • On 3.15, ubuntu and Windows CI hit the swapped order in three scenarios on every run.
  • I found the other three by adding a random delay before each component run.
  • This follows the approach of the 3.14 PR feat: Updates to make Haystack compatible with python 3.14 #10634. AnyOrder gained __iter__ so it can be nested.
• Docs: CONTRIBUTING.md and AGENTS.md are updated for the new range. Until PyPI has cp315 torch wheels, CONTRIBUTING.md explains how to build the test env on 3.15 from the PyTorch CPU index.

How did you test it?

Locally on Python 3.15.0 final (macOS arm64):

• hatch run test:unit: 6754 passed, 10 skipped. All skips are missing-API-key or document-store capability skips.
• hatch run test:integration-only-fast with OPENAI_API_KEY: 315 passed, 19 skipped (Azure credentials and existing skip markers).
• hatch run test:types and hatch run fmt: clean.
• Async feature scenarios with a random 0–10 ms delay before each component run: 40 seeds, no failures.
• Manual: a BM25 → PromptBuilder pipeline with Optional/Union sockets, plus a Pipeline.dumps()/loads() round trip.

In CI, temporary commits switched tests.yml to Python 3.15 and were then reverted, as in #10634.

• Unit and integration passed on ubuntu, macOS and Windows: https://github.com/deepset-ai/haystack/actions/runs/38069150959
• actions/setup-python doesn't list 3.15.0 yet, so that run used 3.15.0rc3.
• Workarounds in that run only:
  • torch from download.pytorch.org/whl/cpu;
  • no jq on Windows, and test_json.py ignored there;
  • pypdf<6.20 (see below).

Notes for the reviewer

• No permanent 3.15 CI job. Like for 3.14, CI keeps testing the floor version (3.11).
• Wheels still missing on 3.15:
  • PyTorch has not uploaded cp315 wheels to PyPI yet; they exist only on its own index.
  • jq 1.12.0 has no cp315 Windows wheel, and its sdist doesn't build on Windows. Windows users on 3.15 can't use JSONConverter with a jq_schema for now. On Linux and macOS, jq builds from sdist.
• Unrelated CI failure: pypdf 6.20.0 (released 2026-10-09) fixed an extraction bug. test_pypdf_to_document.py::test_run_detect_paragraphs_to_be_used_in_split_passage still expects the old "inter nal" text, so it fails on any Python version. test: expect pypdf 6.20 text extraction in PyPDFToDocument test #13203 fixes it; once it merges, I merge main into this PR.
• Found on 3.15, not addressed here: with PYTHON_LAZY_IMPORTS=all (PEP 810), with LazyImport(...) no longer catches a missing optional dependency. check() passes, and users get a raw ModuleNotFoundError at first use instead of the "pip install" hint. The global mode is opt-in, so this needs a follow-up rather than a blocker.

Checklist

• I have read the contributors guidelines and the code of conduct.
• I have updated the related issue with new insights and changes.
• I have added unit tests and updated the docstrings.
• I've used one of the conventional commit types for my PR title: fix:, feat:, build:, chore:, ci:, docs:, style:, refactor:, perf:, test: and added ! in case the PR includes breaking changes.
• I have documented my code.
• I have added a release note file, following the contributors guidelines.
• I have run pre-commit hooks and fixed any issue.

🤖 Generated with Claude Code

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

1 Skipped Deployment

Project	Deployment	Actions	Updated
haystack-docs	Ignored	Preview	Oct 10, 2026 5:07pm UTC

[github-actions]

Coverage report

Click to see where and how coverage changed

File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
haystack/components/converters
multi_file_converter.py
haystack/components/converters/image
image_utils.py
haystack/components/routers
conditional_router.py
haystack/core
type_utils.py
haystack/core/pipeline
base.py
haystack/dataclasses
chat_message.py
haystack/utils
callable_serialization.py
filters.py
Project Total

This report was generated by python-coverage-comment-action