diff --git a/Lib/test/libregrtest/single.py b/Lib/test/libregrtest/single.py
index 958a915626ad24..d0759d2626989d 100644
--- a/Lib/test/libregrtest/single.py
+++ b/Lib/test/libregrtest/single.py
@@ -145,7 +145,7 @@ def regrtest_runner(result: TestResult, test_func, runtests: RunTests) -> None:
 
 
 # Storage of uncollectable GC objects (gc.garbage)
-GC_GARBAGE = []
+GC_GARBAGE: list[object] = []
 
 
 def _load_run_test(result: TestResult, runtests: RunTests) -> None:
diff --git a/Lib/test/test_dict.py b/Lib/test/test_dict.py
index b2f4363b23e748..4efb066d4fd01c 100644
--- a/Lib/test/test_dict.py
+++ b/Lib/test/test_dict.py
@@ -1868,6 +1868,11 @@ def test_merge(self):
         self.assertEqual(fd | {}, fd)
         self.assertEqual(frozendict() | fd, fd)
 
+        # gh-149676: Test hash(frozendict | frozendict)
+        a = frozendict({"a": 1})
+        b = frozendict({"b": 2})
+        self.assertEqual(hash(a | b), hash(frozendict({"a": 1, "b": 2})))
+
     def test_update(self):
         # test "a |= b" operator
         d = frozendict(x=1)
diff --git a/Lib/tomllib/mypy.ini b/Lib/tomllib/mypy.ini
index 1761dce45562a6..f7eeffd575c1c7 100644
--- a/Lib/tomllib/mypy.ini
+++ b/Lib/tomllib/mypy.ini
@@ -12,6 +12,4 @@ pretty = True
 # Enable most stricter settings
 enable_error_code = ignore-without-code
 strict = True
-strict_bytes = True
-local_partial_types = True
 warn_unreachable = True
diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2026-05-11-14-48-56.gh-issue-149676.6aTrw1.rst b/Misc/NEWS.d/next/Core_and_Builtins/2026-05-11-14-48-56.gh-issue-149676.6aTrw1.rst
new file mode 100644
index 00000000000000..96f407cf5ad25a
--- /dev/null
+++ b/Misc/NEWS.d/next/Core_and_Builtins/2026-05-11-14-48-56.gh-issue-149676.6aTrw1.rst
@@ -0,0 +1 @@
+Fix ``frozendict | frozendict`` hash.
diff --git a/Objects/dictobject.c b/Objects/dictobject.c
index 09135e031e6fc7..b33a273dac3b95 100644
--- a/Objects/dictobject.c
+++ b/Objects/dictobject.c
@@ -900,7 +900,7 @@ free_values(PyDictValues *values, bool use_qsbr)
 static inline PyObject *
 new_dict_impl(PyDictObject *mp, PyDictKeysObject *keys,
               PyDictValues *values, Py_ssize_t used,
-              int free_values_on_failure)
+              int free_values_on_failure, int frozendict)
 {
     assert(keys != NULL);
     if (mp == NULL) {
@@ -915,6 +915,9 @@ new_dict_impl(PyDictObject *mp, PyDictKeysObject *keys,
     mp->ma_values = values;
     mp->ma_used = used;
     mp->_ma_watcher_tag = 0;
+    if (frozendict) {
+        ((PyFrozenDictObject *)mp)->ma_hash = -1;
+    }
     ASSERT_CONSISTENT(mp);
     _PyObject_GC_TRACK(mp);
     return (PyObject *)mp;
@@ -931,7 +934,7 @@ new_dict(PyDictKeysObject *keys, PyDictValues *values,
     }
     assert(mp == NULL || Py_IS_TYPE(mp, &PyDict_Type));
 
-    return new_dict_impl(mp, keys, values, used, free_values_on_failure);
+    return new_dict_impl(mp, keys, values, used, free_values_on_failure, 0);
 }
 
 /* Consumes a reference to the keys object */
@@ -940,7 +943,7 @@ new_frozendict(PyDictKeysObject *keys, PyDictValues *values,
                Py_ssize_t used, int free_values_on_failure)
 {
     PyDictObject *mp = PyObject_GC_New(PyDictObject, &PyFrozenDict_Type);
-    return new_dict_impl(mp, keys, values, used, free_values_on_failure);
+    return new_dict_impl(mp, keys, values, used, free_values_on_failure, 1);
 }
 
 static PyObject *
diff --git a/Tools/build/check_extension_modules.py b/Tools/build/check_extension_modules.py
index f23c1d5286f92a..c619a9a0c1c5a1 100644
--- a/Tools/build/check_extension_modules.py
+++ b/Tools/build/check_extension_modules.py
@@ -463,7 +463,7 @@ def get_location(self, modinfo: ModuleInfo) -> pathlib.Path | None:
     def _check_file(self, modinfo: ModuleInfo, spec: ModuleSpec) -> None:
         """Check that the module file is present and not empty"""
         if spec.loader is BuiltinImporter:  # type: ignore[comparison-overlap]
-            return
+            return  # type: ignore[unreachable]
         try:
             assert spec.origin is not None
             st = os.stat(spec.origin)
diff --git a/Tools/build/mypy.ini b/Tools/build/mypy.ini
index 5465e2d4b6171f..485c9314cf7001 100644
--- a/Tools/build/mypy.ini
+++ b/Tools/build/mypy.ini
@@ -24,8 +24,6 @@ python_version = 3.10
 
 # ...And be strict:
 strict = True
-strict_bytes = True
-local_partial_types = True
 extra_checks = True
 enable_error_code = ignore-without-code,redundant-expr,truthy-bool,possibly-undefined
 warn_unreachable = True
diff --git a/Tools/requirements-dev.txt b/Tools/requirements-dev.txt
index af5cbaa7689f33..46381ea58a1238 100644
--- a/Tools/requirements-dev.txt
+++ b/Tools/requirements-dev.txt
@@ -1,7 +1,7 @@
 # Requirements file for external linters and checks we run on
 # Tools/clinic, Tools/cases_generator/, and Tools/peg_generator/ in CI
-mypy==1.19.1
+mypy==2.1.0
 
 # needed for peg_generator:
-types-psutil==7.2.2.20260130
-types-setuptools==82.0.0.20260210
+types-psutil==7.2.2.20260508
+types-setuptools==82.0.0.20260508