diff --git a/tests/architecture/test_contributor_task_board.py b/tests/architecture/test_contributor_task_board.py
index 45d2dcf078..487d4d703e 100644
--- a/tests/architecture/test_contributor_task_board.py
+++ b/tests/architecture/test_contributor_task_board.py
@@ -131,10 +131,10 @@ def test_inactive_or_unmerged_design_cannot_be_available(
 ) -> None:
     run, board, root = check_board
     path = root / "docs/architecture/rfcs/goal-direction-baseline-v0.md"
-    text = path.read_text()
+    text = path.read_text(encoding="utf-8")
     changed = re.sub(r"(?<=RFC status:\*\* )[^\n]+", state, text, count=1)
     assert changed != text
-    path.write_text(changed)
+    path.write_text(changed, encoding="utf-8")
     with pytest.raises(AssertionError, match="not an Accepted claimable design"):
         run(board)
 
diff --git a/tests/architecture/test_rfc_status_index.py b/tests/architecture/test_rfc_status_index.py
index 2da36bfab9..24b2f36987 100644
--- a/tests/architecture/test_rfc_status_index.py
+++ b/tests/architecture/test_rfc_status_index.py
@@ -45,7 +45,9 @@ def document(
             .replace("Supersedes / closes:", "替代 / 关闭：")
             .replace("Superseded by:", "被替代为：")
         )
-    (rfcs / f"{name}{'.zh-CN' if zh else ''}.md").write_text(header + "\n" + body)
+    (rfcs / f"{name}{'.zh-CN' if zh else ''}.md").write_text(
+        header + "\n" + body, encoding="utf-8"
+    )
 
 
 def run(repo: Path, mode: str) -> subprocess.CompletedProcess[str]:
diff --git a/tests/architecture/test_semantic_inventory.py b/tests/architecture/test_semantic_inventory.py
index 3f5a8f3ab6..c9c69beb2f 100644
--- a/tests/architecture/test_semantic_inventory.py
+++ b/tests/architecture/test_semantic_inventory.py
@@ -372,7 +372,10 @@ def test_untracked_sources_do_not_change_inventory(repo: Path) -> None:
 
 def test_tracked_symlink_cannot_read_untracked_source(repo: Path) -> None:
     _write(repo, "private.py", 'PRIVATE_CONTEXT = ("synthetic", "local")\n')
-    (repo / "loopx/link.py").symlink_to(repo / "private.py")
+    try:
+        (repo / "loopx/link.py").symlink_to(repo / "private.py")
+    except OSError as exc:
+        pytest.skip(f"file symlinks unavailable: {exc}")
     subprocess.run(["git", "-C", str(repo), "add", "loopx/link.py"], check=True)
     with pytest.raises(ValueError, match="symlink"):
         load_sources(repo)
diff --git a/tests/architecture/test_semantic_production.py b/tests/architecture/test_semantic_production.py
index 004d35e88c..6b0718058a 100644
--- a/tests/architecture/test_semantic_production.py
+++ b/tests/architecture/test_semantic_production.py
@@ -116,7 +116,7 @@ def test_declared_return_is_scanned_in_real_python_syntax():
 def test_real_return_producer_rejects_an_unregistered_result(vocabulary_name, module, original):
     import json
     from loopx.semantics.inventory import load_sources
-    v = json.loads((ROOT / 'loopx/semantics/vocabulary_v0.json').read_text())['vocabularies'][vocabulary_name]
+    v = json.loads((ROOT / 'loopx/semantics/vocabulary_v0.json').read_text(encoding='utf-8'))['vocabularies'][vocabulary_name]
     sources = load_sources(ROOT)
     replacement = 'return "unknown_action"'
     found = False
@@ -205,7 +205,7 @@ def test_real_effect_adapters_are_observed_as_unresolved_passthrough():
     import json
     from loopx.semantics.inventory import load_sources
 
-    v = json.loads((ROOT / 'loopx/semantics/vocabulary_v0.json').read_text())['vocabularies']['effective_action']
+    v = json.loads((ROOT / 'loopx/semantics/vocabulary_v0.json').read_text(encoding='utf-8'))['vocabularies']['effective_action']
     paths = {'loopx/control_plane/effect_program.py', 'loopx/control_plane/effect_program.ts'}
     owner = v['owners']['python'].split('::')[0]
     sources = [source for source in load_sources(ROOT) if source.path in paths | {owner}]
@@ -249,7 +249,7 @@ def test_real_reexported_turn_owner_is_attributed_through_one_hop():
     from loopx.semantics.inventory import load_sources
     # loop_controller imports LoopXTurnRoute from driver, which re-exports the
     # generated owner; the registered return producer must still resolve.
-    v = json.loads((ROOT / 'loopx/semantics/vocabulary_v0.json').read_text())['vocabularies']['turn_route']
+    v = json.loads((ROOT / 'loopx/semantics/vocabulary_v0.json').read_text(encoding='utf-8'))['vocabularies']['turn_route']
     rows = collect_production(ROOT, v, load_sources(ROOT))
     site = 'loopx/control_plane/turn_driver/loop_controller.py::_envelope_route'
     resolved = {value for r in rows if r.site == site and not r.unresolved for value in r.values}