Add support for free-threaded Python.

Fix #1680.

Author: aaugustin

.github/workflows/tests.yml

@@ -62,6 +62,7 @@ jobs:
           - "3.12"
           - "3.13"
           - "3.14"
+          - "3.14t"
           - "pypy-3.10"
         is_main:
           - ${{ github.event_name == 'push' && github.ref == 'refs/heads/main' }}

docs/project/changelog.rst

@@ -45,6 +45,8 @@ New features
 
 * Validated compatibility with Python 3.14.
 
+* Added support for free-threaded Python.
+
 Improvements
 ............
 

src/websockets/speedups.c

@@ -218,5 +218,12 @@ static struct PyModuleDef speedups_module = {
 PyMODINIT_FUNC
 PyInit_speedups(void)
 {
-    return PyModule_Create(&speedups_module);
+    PyObject *m = PyModule_Create(&speedups_module);
+    if (m == NULL) {
+        return NULL;
+    }
+#ifdef Py_GIL_DISABLED
+    PyUnstable_Module_SetGIL(m, Py_MOD_GIL_NOT_USED);
+#endif
+    return m;
 }