diff --git a/pyodide-build/pyodide_build/out_of_tree/venv.py b/pyodide-build/pyodide_build/out_of_tree/venv.py
index ddfc8be11..6fc9db40a 100644
--- a/pyodide-build/pyodide_build/out_of_tree/venv.py
+++ b/pyodide-build/pyodide_build/out_of_tree/venv.py
@@ -101,7 +101,6 @@ def get_pip_monkeypatch(venv_bin: Path) -> str:
     return dedent(
         """\
         import os
-        import platform
         import sys
         """
         # when pip installs an executable it uses sys.executable to create the
@@ -122,7 +121,6 @@ def get_pip_monkeypatch(venv_bin: Path) -> str:
         orig_platform = sys.platform
         sys.platform = sys_platform
         sys.implementation._multiarch = multiarch
-        platform.system = lambda: sys_platform
         os.environ["_PYTHON_HOST_PLATFORM"] = host_platform
         os.environ["_PYTHON_SYSCONFIGDATA_NAME"] = f'_sysconfigdata_{{sys.abiflags}}_{{sys.platform}}_{{sys.implementation._multiarch}}'
         sys.path.append("{sysconfigdata_dir}")