Core Dispatch #4

Welcome back to Core Dispatch! This edition covers April 30 through May 18, 2026. Python 3.15.0 beta 1 is officially here, which means CPython's main branch is now open for 3.16 work. The first 3.16 alpha is slated for mid-October. More imminently, beta 2 is up next on June 2, with 3.13.14 and 3.14.6 following on June 9.

This is also PyCon US week, so a lot of the core team is gathered in Long Beach right now. Once recordings are available, we'll be sure to pull talks from folks on the team into a future edition.

PEP 788 has also moved from accepted to implemented, and free-threaded builds picked up thread-safe iterator support. There are also a few smaller but concrete fixes: http.server can send custom headers from the command line, AttributeError can suggest Python equivalents for method names from other languages, webbrowser on macOS is moving away from osascript, and ftplib.ftpcp() picked up the PASV CVE fix.

If you maintain a package or just like living on the edge, give the latest 3.15 beta a spin and file any issues you find.