Support for Python 3.14

[pykong]

Describe the request: A clear and concise description. Well, make Azure Functions compatible with Python 3.14 :)

Also, see:

• #1588
• #1397

[cmcconomyfwig]

I realize this is a relatively new version of python; @hallvictoria is there a timeline/roadmap yet for release?

[hallvictoria]

~We will be announcing more details on 3.14 support status & timelines at ignite (11/18)! I'll update this issue once the announcement is made~

~EDIT: announcement has been postponed to 12/10~

EDIT 2: official preview announcement has been postponed. Date TBD.

[hallvictoria]

Current status for Python 3.14 support* (see caveat 1):

You can create Python 3.14 apps through the portal, CLI, and VSCode Extension for Linux Dedicated or Flex Consumption SKUs. The current python version being used in production is 3.14.0rc2. Please note that this update is not an official preview announcement.

Python 3.14 "experimental" support is included in:

• Flex Consumption SKU* (see caveat 2)
• Linux Dedicated SKU
• Core Tools version 4.5.0
• Docker images 4-python3.14-appservice

Important Caveats:

1. We will not be announcing an official preview for Python 3.14 support until December, so the support status right now is "experimental" - it is not officially in preview yet.
2. Remote build is not supported for 3.14 apps in Flex currently - any deployment mechanisms that use remote build in the background will fail in this scenario. For more information, please follow this issue: https://github.com/Azure/azure-functions-python-worker/issues/1801. This limitation does not apply to 3.14 apps in Linux Dedicated.

Upcoming Timeline:

• ~Early December: official preview announcement~ (EDIT: preview announcement date TBD)
• December: prod 3.14 version update to a non-rc version
• January: 3.14 Flex + remote build support

[skvark]

It looks like the RC version is still there. Hit a nasty bug with the RC version today; it looks like Pydantic is not compatible with the RC versions. It means that, for example, FastAPI won't work at all in the preview environment.

Context: https://github.com/pydantic/pydantic/issues/12544#issuecomment-3550784324

I hope that Python 3.14 is updated to a stable version as soon as possible.

[RodriGoncaDeeployer]

It looks like the RC version is still there. Hit a nasty bug with the RC version today; it looks like Pydantic is not compatible with the RC versions. It means that, for example, FastAPI won't work at all in the preview environment.

Context: pydantic/pydantic#12544 (comment)

I hope that Python 3.14 is updated to a stable version as soon as possible.

Same here, a simple import openai breaks the function, as pydantic is a dependency.

I hope it is fixed once it moves to 3.14 final release.

https://github.com/python/cpython/issues/136316

[hallvictoria]

Hey all, thanks for your patience! Here's the current status / upcoming timelines:

Late January / early February: Flex + remote build support (see above comment for workarounds) Early February: official preview announcement February: production version updated to 3.14.0 (release will start early Feb and reach all regions approx. end of Feb)