Add Python 3.14 support, experimental subinterpreter/freethreading support#1279

elprans · 2025-10-13T21:04:29Z

The bulk of the changes here is a rewrite of recordobj.c to use modern
CPython API to properly isolate the module (PEP 489, PEP 573, PEP 630).
This, along with Cython flags, enables support for safely importing
asyncpg in subinterpreters. The Record freelist is now
thread-specific, so asyncpg should be thread-safe at the C level.
Support for subinterpreters and freethreading is EXPERIMENTAL.

ddanier · 2025-10-14T14:54:02Z

As of no pre-built package being available for asyncpg on Python 3.14 you cannot install the package on "slim" docker images, cause gcc is not installed there. This is an issue as you tend to use those "slim" variants when you care about security. Of course it is possible to get this working by either compiling this package yourself on a non-"slim" image and then use a multistage build or switching to the non-"slim" version, but that either does increase complexity or reduce security significantly.

What I want to say: I really would like this to get finished and merged soon. Thanks for all the effort! ;-)

asyncpg/record/recordobj.c

.github/workflows/tests.yml

asyncpg/protocol/codecs/base.pyx

1st1 · 2025-10-20T16:33:53Z

asyncpg/record/recordobj.c

@@ -0,0 +1,1281 @@
+/* Big parts of this file are copied (with modifications) from


Any reason for this file to be moved? No diff now, all code is like new which makes review harder

There were some odd Cython issues initially, but I'll see if I can move it back.

Done, @1st1, please take another look.

1st1

Can we move recordobj.c back where it was?

elprans · 2025-10-20T16:35:36Z

Can we move recordobj.c back where it was?

I couldn't find a way to do it. Cython does not expose a way to plug into its generated module state, so record must be a standalone module, not a concatenation. Why is this important?

1st1 · 2025-10-20T16:39:59Z

I couldn't find a way to do it. Cython does not expose a way to plug into its generated module state, so record must be a standalone module, not a concatenation. Why is this important?

Just for me to review the thing, it's a big file. Were there any changes in it?

…pport The bulk of the changes here is a rewrite of `recordobj.c` to use modern CPython API to properly isolate the module (PEP 489, PEP 573, PEP 630). This, along with Cython flags, enables support for safely importing `asyncpg` in subinterpreters. The `Record` freelist is now thread-specific, so asyncpg should be thread-safe *at the C level*. Support for subinterpreters and freethreading is EXPERIMENTAL.

asyncpg/protocol/record/recordobj.c

1st1 · 2025-10-20T20:12:36Z

asyncpg/protocol/record/recordobj.c

 v_is_tuple=1;
 }
-elseif (ApgRecord_CheckExact(v)){
+elseif (v_type==state->ApgRecord_Type){


I'd keep the ApgRecord_CheckExact macros, just make it accept state as first arg.

1st1 · 2025-10-20T20:13:07Z

asyncpg/protocol/record/recordobj.c

+cmp=vlen >= wlen;
+break;
+default:
+returnNULL; /* cannot happen */


Py_UNREACHABLE();

tests/test_subinterpreters.py

1st1

looks ok but please run tests in refleak hunt mode

asyncpg/protocol/record/recordobj.c

bfontaine · 2025-11-21T14:12:08Z

When is this expected to be released?

@elprans

Enable Python 3.14 with experimental subinterpreter/freethreading support. Improvements ============ * Add Python 3.14 support, experimental subinterpreter/freethreading support (#1279) (by @elprans in 9e42642) * Avoid performing type introspection on known types (#1243) (by @elprans in 5c9986c) * Make `prepare()` not use named statements by default when cache is disabled (#1245) (by @elprans in 5b14653) * Implement connection service file functionality (#1223) (by @AndrewJackson2020 in 1d63bb1) Fixes ===== * Fix multi port connection string issue (#1222) (by @AndrewJackson2020 in 01c0db7) * Avoid leaking connections if _can_use_connection fails (#1269) (by @yuliy-openai in e94302d) Other ===== * Drop support for EOL Python 3.8 (#1281) (by @elprans in 6c2c490)

@elprans

asyncpg v0.31.0 Enable Python 3.14 with experimental subinterpreter/freethreading support. Improvements ============ * Add Python 3.14 support, experimental subinterpreter/freethreading support (MagicStack#1279) (by @elprans in 9e42642) * Avoid performing type introspection on known types (MagicStack#1243) (by @elprans in 5c9986c) * Make `prepare()` not use named statements by default when cache is disabled (MagicStack#1245) (by @elprans in 5b14653) * Implement connection service file functionality (MagicStack#1223) (by @AndrewJackson2020 in 1d63bb1) Fixes ===== * Fix multi port connection string issue (MagicStack#1222) (by @AndrewJackson2020 in 01c0db7) * Avoid leaking connections if _can_use_connection fails (MagicStack#1269) (by @yuliy-openai in e94302d) Other ===== * Drop support for EOL Python 3.8 (MagicStack#1281) (by @elprans in 6c2c490) # -----BEGIN PGP SIGNATURE----- # # iQIzBAABCAAdFiEES/rQWfT9RAppNY3YXEaHeAYth78FAmkk6UMACgkQXEaHeAYt # h7+LBw//fX/3/nHrEUctYR7A/WQqg2oj3nvk10b3OQjzHUGyHq0DhkSC7/H9P0FI # vl0j2n+BfKcKxOw4OgbxDq5fff/a4ScsejVwsKqQEEDH9tiXAL2cIId1yvNWC9hJ # 8WxmkJzbFHdrl1D3/pxUv15UoaMSZD1DtPXaYEupRyEKXVOfQ/ush5GU5M3vA19R # aWrAFtbMd3MMfaBYEO1TQtZNCV3n3Dv8fmIwv8qPbqJt2lsk4HOE8F3Be/RGiaPZ # dI9eGnZ+qmlYC/mZYKNywaBlm4v/hHhuGwSh8WdkY6h4lFkBl8HipuPpoNeWO/fd # k5wl1Q2HA8i2qEokz7EzYPRYjOPZwXphxscRXJQbdlCNyfJ+lPTu3uAQ08RTnoGU # +JROauwgtQknnZEGtRWNerRcbZE1D+SgkLhGkEk6+tcIJ0G2XoCsn7A/u9LMmZuN # 7lcFnLEdDnUSaLx7SZgcbOKP1Acg1W2Vk375JxXrymGqq5FPss8cdg+KOFMNuljT # v/RtKvAP3yXpR448uPQ6M4BNVJ5my3UwdPrHwpGNkSxaqKBGGtryBG4LLw43yPCg # FPFO9P//z+59RsmAvilaOhT/pLhqRvOJTkaUt5bt6Fw+5SzCfNfciNkl4rBC+9EQ # LC/NQmO9cFYlpnO7s3uF0M+JTLV1u0CJp5G5USiQiEU+tVlaH6E= # =bEvL # -----END PGP SIGNATURE----- # gpg: Signature made Tue 25 Nov 2025 12:24:51 AM CET # gpg: using RSA key 4BFAD059F4FD440A69358DD85C468778062D87BF # gpg: Can't check signature: No public key

@elprans

asyncpg v0.31.0 Enable Python 3.14 with experimental subinterpreter/freethreading support. Improvements ============ * Add Python 3.14 support, experimental subinterpreter/freethreading support (MagicStack#1279) (by @elprans in 9e42642) * Avoid performing type introspection on known types (MagicStack#1243) (by @elprans in 5c9986c) * Make `prepare()` not use named statements by default when cache is disabled (MagicStack#1245) (by @elprans in 5b14653) * Implement connection service file functionality (MagicStack#1223) (by @AndrewJackson2020 in 1d63bb1) Fixes ===== * Fix multi port connection string issue (MagicStack#1222) (by @AndrewJackson2020 in 01c0db7) * Avoid leaking connections if _can_use_connection fails (MagicStack#1269) (by @yuliy-openai in e94302d) Other ===== * Drop support for EOL Python 3.8 (MagicStack#1281) (by @elprans in 6c2c490) # -----BEGIN PGP SIGNATURE----- # # iQIzBAABCAAdFiEES/rQWfT9RAppNY3YXEaHeAYth78FAmkk6UMACgkQXEaHeAYt # h7+LBw//fX/3/nHrEUctYR7A/WQqg2oj3nvk10b3OQjzHUGyHq0DhkSC7/H9P0FI # vl0j2n+BfKcKxOw4OgbxDq5fff/a4ScsejVwsKqQEEDH9tiXAL2cIId1yvNWC9hJ # 8WxmkJzbFHdrl1D3/pxUv15UoaMSZD1DtPXaYEupRyEKXVOfQ/ush5GU5M3vA19R # aWrAFtbMd3MMfaBYEO1TQtZNCV3n3Dv8fmIwv8qPbqJt2lsk4HOE8F3Be/RGiaPZ # dI9eGnZ+qmlYC/mZYKNywaBlm4v/hHhuGwSh8WdkY6h4lFkBl8HipuPpoNeWO/fd # k5wl1Q2HA8i2qEokz7EzYPRYjOPZwXphxscRXJQbdlCNyfJ+lPTu3uAQ08RTnoGU # +JROauwgtQknnZEGtRWNerRcbZE1D+SgkLhGkEk6+tcIJ0G2XoCsn7A/u9LMmZuN # 7lcFnLEdDnUSaLx7SZgcbOKP1Acg1W2Vk375JxXrymGqq5FPss8cdg+KOFMNuljT # v/RtKvAP3yXpR448uPQ6M4BNVJ5my3UwdPrHwpGNkSxaqKBGGtryBG4LLw43yPCg # FPFO9P//z+59RsmAvilaOhT/pLhqRvOJTkaUt5bt6Fw+5SzCfNfciNkl4rBC+9EQ # LC/NQmO9cFYlpnO7s3uF0M+JTLV1u0CJp5G5USiQiEU+tVlaH6E= # =bEvL # -----END PGP SIGNATURE----- # gpg: Signature made Tue 25 Nov 2025 12:24:51 AM CET # gpg: using RSA key 4BFAD059F4FD440A69358DD85C468778062D87BF # gpg: Can't check signature: No public key

elprans force-pushed the py314 branch from 66b21e8 to e2427b2Compare October 13, 2025 21:20

elprans force-pushed the py314 branch from e2427b2 to f21c7d4Compare October 16, 2025 18:49

elprans changed the title ~~Add Python 3.14 support, drop EOL 3.8~~Add Python 3.14 support, experimental subinterpreter/freethreading supportOct 16, 2025

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fantix reviewed Oct 16, 2025
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frankie567 mentioned this pull request Oct 18, 2025
Python free-threading support polarsource/polar#7342
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