Free-threaded Python (Interview)

The Changelog: Software Development, Open Source

Jerod is joined by the co-hosts of core.py , Pablo Galindo & Łukasz Langa, a podcast about Python internals by people who work on Python internals. Python 3.13 is right around the corner, which means the Global Interpeter Lock (GIL) is now experimentally optional! This is a huge deal as Python is finally free-threaded. There’s more to discuss, of course, so we get into all the gory details.

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Featuring:

• Pablo Galindo – GitHub, X
• Łukasz Langa – Website, GitHub, Mastodon, X
• Jerod Santo – GitHub, LinkedIn, Mastodon, X

Show Notes:

• core.py
• What’s New In Python 3.13
• Free-threaded compatibility status tracking
• 🧵 Free-Threaded Wheels

Something missing or broken? PRs welcome!

บท

1. This is The Changelog (00:00:00)

2. Sponsor: Sentry (00:02:01)

https://sentry.io/

3. Start the show! (00:03:43)

4. Starting core.py (00:04:27)

https://podcasters.spotify.com/pod/show/corepy

5. Keeping up with Pablo (00:07:22)

6. Magical closed captioning (00:09:03)

7. Shout out to Christian Clauss! (00:11:00)

8. What is the GIL (00:11:35)

9. Working around it (00:13:46)

10. Causes of Python slowness (00:16:56)

11. Sponsor: Fly.io (00:21:44)

https://fly.io/

12. Sponsor: Coder.com (00:25:11)

https://coder.com/

13. Worth the effort? (00:27:15)

14. A separate executable (00:28:17)

15. Slower for now or for good? (00:30:46)

16. Early indicators (00:34:35)

17. Time to adopt? (00:39:33)

18. Just-in-time (JIT) compiler (00:44:17)

19. Sponsor: Unblocked (00:52:26)

https://getunblocked.com

20. The 1-year release cadence (00:55:27)

21. iOS compatibility (01:10:26)

22. Wishlists for 3.14 (01:18:42)

23. Flyyyy free-threaded (yeah) (01:23:41)

24. Coming up next (01:24:35)

https://changelog.com/community