diff --git a/.github/workflows/release-performance.yml b/.github/workflows/release-performance.yml
index aaf705d6ed..a02c75e8d9 100644
--- a/.github/workflows/release-performance.yml
+++ b/.github/workflows/release-performance.yml
@@ -62,7 +62,9 @@ jobs:
       - name: Install dependencies
         run: uv sync --locked --all-groups --all-extras
       - name: Build candidate wheel
-        run: uv build --wheel --out-dir "${RUNNER_TEMP}/candidate"
+        run: |
+          uv build --wheel --out-dir "${RUNNER_TEMP}/candidate"
+          uv build --wheel crates/sqlbuild-cli --out-dir "${RUNNER_TEMP}/candidate"
       # Temporary: one-model edit compiles use MAX_EDIT_COMPILE_TIME_RATIO (1.35x) because an edited
       # model recompiles uncached; tighten it back to 1.15x once native rendering is the default.
       - name: Compare candidate and previous release on this runner
diff --git a/scripts/release_performance/_helpers/versions.py b/scripts/release_performance/_helpers/versions.py
index 2c9ddeeefe..5d66ce8cbe 100644
--- a/scripts/release_performance/_helpers/versions.py
+++ b/scripts/release_performance/_helpers/versions.py
@@ -196,7 +196,8 @@ def install_wheel(*, wheel: Path, venv_dir: Path, python: str) -> Path:
 
     _create_venv(venv_dir=venv_dir, python=python)
     completed: subprocess.CompletedProcess[str] = _uv_pip_install(
-        venv_dir=venv_dir, requirements=(str(wheel.resolve()),)
+        venv_dir=venv_dir,
+        requirements=("--find-links", str(wheel.resolve().parent), str(wheel.resolve())),
     )
     if completed.returncode != 0:
         raise ReleasePerformanceError(f"Installing {wheel} failed: {_tail(completed.stderr)}")
diff --git a/tests/integration/scripts/__init__.py b/tests/integration/scripts/__init__.py
new file mode 100644
index 0000000000..66c5503022
--- /dev/null
+++ b/tests/integration/scripts/__init__.py
@@ -0,0 +1 @@
+"""Integration checks for repository tooling."""
diff --git a/tests/integration/scripts/release_performance/__init__.py b/tests/integration/scripts/release_performance/__init__.py
new file mode 100644
index 0000000000..0946f1f325
--- /dev/null
+++ b/tests/integration/scripts/release_performance/__init__.py
@@ -0,0 +1 @@
+"""Release candidate installation integration checks."""
diff --git a/tests/integration/scripts/release_performance/_test_types.py b/tests/integration/scripts/release_performance/_test_types.py
new file mode 100644
index 0000000000..9cf297cd37
--- /dev/null
+++ b/tests/integration/scripts/release_performance/_test_types.py
@@ -0,0 +1,12 @@
+"""Local candidate installation cases."""
+
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class LocalWheelTestCase:
+    """A synchronized candidate and companion version."""
+
+    description: str
+    version: str
+    expected_version: str
diff --git a/tests/integration/scripts/release_performance/test_local_wheels.py b/tests/integration/scripts/release_performance/test_local_wheels.py
new file mode 100644
index 0000000000..3c77848d5b
--- /dev/null
+++ b/tests/integration/scripts/release_performance/test_local_wheels.py
@@ -0,0 +1,53 @@
+"""Exercise candidate installation with an unpublished companion wheel."""
+
+import sys
+from pathlib import Path
+from zipfile import ZipFile
+
+import pytest
+
+from scripts.release_performance._helpers.versions import install_wheel, installed_version
+from tests.integration.scripts.release_performance._test_types import LocalWheelTestCase
+
+
+@pytest.mark.skipif(sys.platform == "win32", reason="Release comparison uses POSIX environments")
+@pytest.mark.parametrize(
+    "test_case",
+    [
+        LocalWheelTestCase(
+            description="unpublished companion installs offline beside its candidate",
+            version="0.1.0",
+            expected_version="0.1.0",
+        )
+    ],
+    ids=lambda case: case.description,
+)
+def test_given_unpublished_companion_when_installing_candidate_then_resolves_local_wheel(
+    test_case: LocalWheelTestCase, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    monkeypatch.setenv("UV_NO_INDEX", "1")
+    wheels: Path = tmp_path / "wheels"
+    wheels.mkdir()
+    version: str = test_case.version
+    for name, dependency, entry_points in (
+        ("sqlbuild", f"Requires-Dist: sqlbuild-cli=={version}\n", ""),
+        ("sqlbuild_cli", "", "[console_scripts]\nsqb = sqlbuild_cli_probe:main\n"),
+    ):
+        metadata: str = f"Metadata-Version: 2.1\nName: {name}\nVersion: {version}\n{dependency}"
+        with ZipFile(wheels / f"{name}-{version}-py3-none-any.whl", "w") as wheel:
+            info: str = f"{name}-{version}.dist-info"
+            wheel.writestr(f"{info}/METADATA", metadata)
+            wheel.writestr(
+                f"{info}/WHEEL",
+                "Wheel-Version: 1.0\nGenerator: release-probe\n"
+                "Root-Is-Purelib: true\nTag: py3-none-any\n",
+            )
+            wheel.writestr(f"{info}/RECORD", "")
+            wheel.writestr(f"{name}_probe.py", f"def main():\n    print('sqlbuild {version}')\n")
+            wheel.writestr(f"{info}/entry_points.txt", entry_points)
+    sqb: Path = install_wheel(
+        wheel=wheels / f"sqlbuild-{version}-py3-none-any.whl",
+        venv_dir=tmp_path / "candidate",
+        python=sys.executable,
+    )
+    assert installed_version(sqb=sqb) == test_case.expected_version