diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f73907ae6..f091ee71a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -231,6 +231,17 @@ jobs:
         python-version: ['3.10', '3.11', '3.12', '3.13', '3.14']
     timeout-minutes: 15
 
+    # Without this the matrix is decorative. `make dev` runs a bare `uv sync`,
+    # and uv resolves its interpreter from .python-version (pinned to 3.11)
+    # rather than from whatever actions/setup-python just installed -- so every
+    # leg built a 3.11 venv and all four ran the same interpreter. UV_PYTHON
+    # takes precedence over the pin file, which restores real version coverage.
+    #
+    # Set at job level, not on the install step: `make ci-quality-github` runs
+    # `uv run pytest`, which resolves the interpreter again.
+    env:
+      UV_PYTHON: ${{ matrix.python-version }}
+
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
diff --git a/tests/unit/cli/commands/test_run_server_helpers.py b/tests/unit/cli/commands/test_run_server_helpers.py
index 60ae9a14d..80a3feb60 100644
--- a/tests/unit/cli/commands/test_run_server_helpers.py
+++ b/tests/unit/cli/commands/test_run_server_helpers.py
@@ -336,12 +336,34 @@ async def test_allows_populated_fields(self):
         assert result == {"echo": "hello"}
         func.assert_called_once_with(msg="hello")
 
+    # These two wrap the mock in a real async def instead of passing the mock
+    # straight to call_with_body.
+    #
+    # call_with_body -> _map_body_to_params calls inspect.signature(func), and
+    # signature() of a Mock is version-dependent: on 3.10 it raises
+    # `TypeError: 'Mock' object is not subscriptable` (Mock auto-creates a
+    # __signature__ child, which inspect then tries to use), while on 3.11+ it
+    # reports (*args, **kwargs). Passing spec= does not help -- the failure is
+    # in signature(), not in spec resolution.
+    #
+    # call_with_body catches Exception and converts it into a 500 JSONResponse,
+    # so on 3.10 these failed as `assert <JSONResponse object> == {'ok': True}`,
+    # with the real TypeError visible only inside the response body.
+    #
+    # The wrapper declares (*args, **kwargs), the same signature 3.11+ inferred
+    # from the Mock, so both branches of _map_body_to_params behave exactly as
+    # before -- and delegating to the mock keeps the call assertions.
+
     @pytest.mark.asyncio
     async def test_allows_plain_dict_body(self):
         """Non-empty plain dict passes through unchanged (no model_fields_set)."""
         body = {"key": "value"}
 
-        func = AsyncMock(return_value={"ok": True})
+        mock = AsyncMock(return_value={"ok": True})
+
+        async def func(*args, **kwargs):
+            return await mock(*args, **kwargs)
+
         result = await call_with_body(func, body)
 
         assert result == {"ok": True}
@@ -354,8 +376,12 @@ async def test_allows_empty_plain_dict_body(self):
         """
         body = {}
 
-        func = AsyncMock(return_value={"ok": True})
+        mock = AsyncMock(return_value={"ok": True})
+
+        async def func(*args, **kwargs):
+            return await mock(*args, **kwargs)
+
         result = await call_with_body(func, body)
 
         assert result == {"ok": True}
-        func.assert_called_once_with()
+        mock.assert_called_once_with()
diff --git a/tests/unit/core/resources/test_resource_manager_extended.py b/tests/unit/core/resources/test_resource_manager_extended.py
index 06f2ac1eb..fe24a8f85 100644
--- a/tests/unit/core/resources/test_resource_manager_extended.py
+++ b/tests/unit/core/resources/test_resource_manager_extended.py
@@ -9,6 +9,17 @@
 )
 
 
+class _LegacyResource:
+    """Minimal picklable stand-in for a resource in the pre-1.12 state file.
+
+    Module-level, not defined inside a test: cloudpickle serialises a class
+    defined in a function body by value, which is the thing being avoided here.
+    """
+
+    def __init__(self, config_hash: str):
+        self.config_hash = config_hash
+
+
 @pytest.fixture(autouse=True)
 def reset_manager(isolate_resource_state_file, reset_singletons):
     """Reset singleton and state file between tests."""
@@ -56,7 +67,13 @@ def test_loads_legacy_dict_format(self, tmp_path):
         state_file = tmp_path / ".runpod" / "resources.pkl"
         state_file.parent.mkdir(parents=True)
 
-        resources = {"key1": MagicMock(config_hash="hash1")}
+        # A plain object rather than MagicMock: whether cloudpickle can pickle a
+        # Mock is version-dependent, and on 3.10 this failed with
+        # "Could not pickle object as excessively deep recursion required".
+        # Only .config_hash is read here (via _refresh_config_hashes), and the
+        # absence of get_resource_key is what keeps the legacy key un-migrated,
+        # which is exactly what this test is asserting.
+        resources = {"key1": _LegacyResource("hash1")}
         with open(state_file, "wb") as f:
             cloudpickle.dump(resources, f)