Python 3.15.0a5 has been released. This release is not yet ready for prime-time use and should only be used for testing and feedback purposes, with caution advised due to its experimental nature. The upcoming Python 3.15 features several notable improvements, including a new profiler, simplified UTF-8 handling through PEP 686, and updates to C API object building via PEP 782. Developers are encouraged to test the current alpha release and share their findings as the development team continues to refine the system ahead of beta releases next month.

Python 3.15.0 Alpha 5 released

A new alpha release for the upcoming Python 3.15 has been made available to developers.  This is the fifth build in their early testing series this time around, labeled as 3.15.0a5, and it tackles a problem they'd introduced earlier in Alpha 4.

Think of these alphas like early explorers' maps. They're still very much works-in-progress, definitely not ready for prime-time use. Python is letting developers know that more alpha releases are planned before moving to beta next month (May), which gives them time to keep tinkering with new ideas and adjusting things until the end of July in 2026.

Take caution: do not use this preview for any important or live systems just yet. The Python folks aren't encouraging anyone to rely on it seriously; they're asking developers to dive in, play around, run some tests, and share what they find. This is a critical period for feedback as they refine the system.

There are several notable tweaks planned for Python 3.15, including this release. One interesting new feature is a profiler designed for peeking at performance issues without costing much in in itself. Alongside that, you can expect PEP 686 to make UTF-8 handling simpler right from the start by setting it as the default encoding and also see what happens with PEP 782's updates to how C APIs build certain kinds of objects.

The changes don't stop there. The JIT compiler gets a significant upgrade, which promises some speed boosts, maybe a few percent faster on specific setups than before Alpha 4 dropped. And you'll probably find the error messages clearer in this version too.

Remember that the current release is still very much experimental software. Don't bet the farm on it or use it for anything mission-critical right now. The development team knows there's plenty left to do and will be releasing another alpha build sometime next year, likely around February 10th.

If you're curious about testing Python 3.15 early and seeing what these updates look like in action, head over to the official website and grab the current alpha from there.