diff --git a/tests/fixtures/audit_inputs/audit_exception_handling.json b/tests/fixtures/audit_inputs/audit_exception_handling.json
new file mode 100644
index 00000000..37825185
--- /dev/null
+++ b/tests/fixtures/audit_inputs/audit_exception_handling.json
@@ -0,0 +1,6 @@
+{
+ "findings": [
+  {"file": "tests/fixtures/synthetic_src/ai_client.py", "line": 14, "category": "BOUNDARY_SDK", "function": "send_result", "class": null, "body_summary": "try/except + Result conversion"},
+  {"file": "tests/fixtures/synthetic_src/aggregate.py", "line": 11, "category": "BOUNDARY_SDK", "function": "build_file_items", "class": null, "body_summary": "try/except + Result conversion"}
+ ]
+}
\ No newline at end of file
diff --git a/tests/fixtures/audit_inputs/audit_main_thread_imports.json b/tests/fixtures/audit_inputs/audit_main_thread_imports.json
new file mode 100644
index 00000000..d02ed893
--- /dev/null
+++ b/tests/fixtures/audit_inputs/audit_main_thread_imports.json
@@ -0,0 +1,3 @@
+{
+ "findings": []
+}
\ No newline at end of file
diff --git a/tests/fixtures/audit_inputs/audit_no_models_config_io.json b/tests/fixtures/audit_inputs/audit_no_models_config_io.json
new file mode 100644
index 00000000..d02ed893
--- /dev/null
+++ b/tests/fixtures/audit_inputs/audit_no_models_config_io.json
@@ -0,0 +1,3 @@
+{
+ "findings": []
+}
\ No newline at end of file
diff --git a/tests/fixtures/audit_inputs/audit_optional_in_3_files.json b/tests/fixtures/audit_inputs/audit_optional_in_3_files.json
new file mode 100644
index 00000000..d02ed893
--- /dev/null
+++ b/tests/fixtures/audit_inputs/audit_optional_in_3_files.json
@@ -0,0 +1,3 @@
+{
+ "findings": []
+}
\ No newline at end of file
diff --git a/tests/fixtures/audit_inputs/audit_weak_types.json b/tests/fixtures/audit_inputs/audit_weak_types.json
new file mode 100644
index 00000000..510c2066
--- /dev/null
+++ b/tests/fixtures/audit_inputs/audit_weak_types.json
@@ -0,0 +1,8 @@
+{
+ "findings": [
+  {"file": "tests/fixtures/synthetic_src/ai_client.py", "line": 14, "type_string": "dict[str, Any]", "category": "untyped_dict"},
+  {"file": "tests/fixtures/synthetic_src/ai_client.py", "line": 18, "type_string": "dict[str, Any]", "category": "untyped_dict"},
+  {"file": "tests/fixtures/synthetic_src/aggregate.py", "line": 11, "type_string": "list[dict[str, Any]]", "category": "untyped_list"},
+  {"file": "tests/fixtures/synthetic_src/aggregate.py", "line": 17, "type_string": "dict[str, Any]", "category": "untyped_dict"}
+ ]
+}
\ No newline at end of file
diff --git a/tests/fixtures/audit_inputs/type_registry.json b/tests/fixtures/audit_inputs/type_registry.json
new file mode 100644
index 00000000..203dba7c
--- /dev/null
+++ b/tests/fixtures/audit_inputs/type_registry.json
@@ -0,0 +1,16 @@
+{
+ "types": {
+  "Metadata": {
+   "file": "src/type_aliases.py",
+   "fields": [{"name": "role", "type": "str", "optional": false}, {"name": "content", "type": "str", "optional": false}]
+  },
+  "FileItems": {
+   "file": "src/type_aliases.py",
+   "fields": [{"name": "path", "type": "str", "optional": false}, {"name": "view_mode", "type": "str", "optional": false}]
+  },
+  "History": {
+   "file": "src/type_aliases.py",
+   "fields": [{"name": "role", "type": "str", "optional": false}, {"name": "content", "type": "str", "optional": false}]
+  }
+ }
+}
\ No newline at end of file
diff --git a/tests/fixtures/synthetic_src/aggregate.py b/tests/fixtures/synthetic_src/aggregate.py
new file mode 100644
index 00000000..5bb55800
--- /dev/null
+++ b/tests/fixtures/synthetic_src/aggregate.py
@@ -0,0 +1,17 @@
+"""Synthetic aggregate module for the v2 audit integration tests."""
+from __future__ import annotations
+from typing import Any
+
+FileItems = list[dict[str, Any]]
+
+def build_file_items() -> list[dict[str, Any]]:
+ data: FileItems = [{"path": "a.py", "view_mode": "full"}, {"path": "b.py", "view_mode": "summary"}]
+ return data
+
+def format_paths(items: FileItems) -> list[str]:
+ out: list[str] = []
+ for item in items:
+  path = item["path"]
+  view_mode = item["view_mode"]
+  out.append(f"{path}:{view_mode}")
+ return out
\ No newline at end of file
diff --git a/tests/fixtures/synthetic_src/ai_client.py b/tests/fixtures/synthetic_src/ai_client.py
new file mode 100644
index 00000000..fc3d6029
--- /dev/null
+++ b/tests/fixtures/synthetic_src/ai_client.py
@@ -0,0 +1,26 @@
+"""Synthetic AI client for the v2 audit integration tests."""
+from __future__ import annotations
+from typing import Any
+
+Metadata = dict[str, Any]
+History = list[dict[str, Any]]
+
+def send_result() -> dict[str, Any]:
+ data: Metadata = {"role": "user", "content": "hello"}
+ return data
+
+def append_history() -> list[dict[str, Any]]:
+ data: History = []
+ return data
+
+def to_list(history: History) -> History:
+ out: History = []
+ for entry in history:
+  role = entry["role"]
+  content = entry["content"]
+  out.append({"role": role, "content": content})
+ return out
+
+def process(metadata: Metadata) -> str:
+ role = metadata["role"]
+ return role
\ No newline at end of file
diff --git a/tests/fixtures/synthetic_src/cleanup.py b/tests/fixtures/synthetic_src/cleanup.py
new file mode 100644
index 00000000..44e30759
--- /dev/null
+++ b/tests/fixtures/synthetic_src/cleanup.py
@@ -0,0 +1,9 @@
+"""Synthetic cleanup module for the v2 audit integration tests."""
+from __future__ import annotations
+from typing import Any
+
+Metadata = dict[str, Any]
+
+def do_nothing(metadata: Metadata) -> None:
+ role = metadata["role"]
+ _ = role
\ No newline at end of file
diff --git a/tests/fixtures/synthetic_src/gui_2.py b/tests/fixtures/synthetic_src/gui_2.py
new file mode 100644
index 00000000..8b0ba376
--- /dev/null
+++ b/tests/fixtures/synthetic_src/gui_2.py
@@ -0,0 +1,10 @@
+"""Synthetic GUI module for the v2 audit integration tests."""
+from __future__ import annotations
+from typing import Any
+
+FileItems = list[dict[str, Any]]
+
+def render_file_list(items: FileItems) -> None:
+ for item in items:
+  path = item["path"]
+  print(path)
\ No newline at end of file
diff --git a/tests/fixtures/synthetic_src/overrides.toml b/tests/fixtures/synthetic_src/overrides.toml
new file mode 100644
index 00000000..e474b46b
--- /dev/null
+++ b/tests/fixtures/synthetic_src/overrides.toml
@@ -0,0 +1,5 @@
+[memory_dim]
+# (empty; the canonical mappings cover the 3 aggregates)
+
+[frequency]
+"tests.fixtures.synthetic_src.cleanup.do_nothing" = "cold"
\ No newline at end of file
diff --git a/tests/fixtures/synthetic_src/type_aliases.py b/tests/fixtures/synthetic_src/type_aliases.py
new file mode 100644
index 00000000..f45b28af
--- /dev/null
+++ b/tests/fixtures/synthetic_src/type_aliases.py
@@ -0,0 +1,13 @@
+"""Synthetic type aliases for the v2 audit integration tests.
+
+Defines 3 TypeAliases: Metadata, FileItems, History. These are
+the same names as in src/type_aliases.py (canonical TypeAliases)
+but live in the test fixture so the integration tests can run
+without depending on the real src/.
+"""
+from __future__ import annotations
+from typing import Any, TypeAlias
+
+Metadata: TypeAlias = dict[str, Any]
+FileItems: TypeAlias = list[dict[str, Any]]
+History: TypeAlias = list[dict[str, Any]]
\ No newline at end of file