This is an early developer preview of Python 3.15
www.python.org/downloads/release/python-3150a3/
Python 3.15 is still in development. This release, 3.15.0a3, is the third of seven planned alpha releases.
Alpha releases are intended to make it easier to test the current state of new features and bug fixes and to test the release process.
During the alpha phase, features may be added up until the start of the beta phase (2026-05-05) and, if necessary, may be modified or deleted up until the release candidate phase (2026-07-28). Please keep in mind that this is a preview release and its use is not recommended for production environments.
Many new features for Python 3.15 are still being planned and written. Among the new major new features and changes so far:
PyBytesWriter C API to create a Python bytes objectThe next pre-release of Python 3.15 will be 3.15.0a4, currently scheduled for 2026-01-13.
Instantly the captain ran forward, and in a loud voice commanded his crew to desist from hoisting the cutting-tackles, and at once cast loose the cables and chains confining the whales to the ship.
“What now?” said the Guernsey-man, when the Captain had returned to them.
“Why, let me see; yes, you may as well tell him now that—that—in fact, tell him I’ve diddled him, and (aside to himself) perhaps somebody else.”
Thanks to all of the many volunteers who help make Python Development and these releases possible! Please consider supporting our efforts by volunteering yourself or through organisation contributions to the Python Software Foundation.
Regards from an even deeper darker Helsinki,
Your release team,
Hugo van Kemenade
Ned Deily
Steve Dower
Łukasz Langa