diff --git a/justfile b/justfile
index 9297c372a..ab2fbc636 100644
--- a/justfile
+++ b/justfile
@@ -33,8 +33,8 @@ app-server-test-client *args:
 # Format Rust and Python SDK code.
 fmt:
     cargo fmt -- --config imports_granularity=Item 2>/dev/null
-    uv run --project ../sdk/python --extra dev ruff check --fix --fix-only ../sdk/python
-    uv run --project ../sdk/python --extra dev ruff format ../sdk/python
+    uv run --frozen --project ../sdk/python --extra dev ruff check --fix --fix-only ../sdk/python
+    uv run --frozen --project ../sdk/python --extra dev ruff format ../sdk/python
 
 fix *args:
     cargo clippy --fix --tests --allow-dirty "$@"
diff --git a/sdk/python/tests/test_artifact_workflow_and_binaries.py b/sdk/python/tests/test_artifact_workflow_and_binaries.py
index 4a8e4df4d..b43cdd570 100644
--- a/sdk/python/tests/test_artifact_workflow_and_binaries.py
+++ b/sdk/python/tests/test_artifact_workflow_and_binaries.py
@@ -66,8 +66,8 @@ def test_root_fmt_recipe_formats_rust_and_python_sdk() -> None:
         "previous_attribute": "# Format Rust and Python SDK code.",
         "commands": [
             "cargo fmt -- --config imports_granularity=Item 2>/dev/null",
-            "uv run --project ../sdk/python --extra dev ruff check --fix --fix-only ../sdk/python",
-            "uv run --project ../sdk/python --extra dev ruff format ../sdk/python",
+            "uv run --frozen --project ../sdk/python --extra dev ruff check --fix --fix-only ../sdk/python",
+            "uv run --frozen --project ../sdk/python --extra dev ruff format ../sdk/python",
         ],
     }