---
 pyproject.toml                                                       |    3 +++
 tests/tox_env/python/virtual_env/package/test_package_cmd_builder.py |    1 +
 2 files changed, 4 insertions(+)

--- a/pyproject.toml
+++ b/pyproject.toml
@@ -162,6 +162,9 @@ ignore = [
 [tool.pytest.ini_options]
 testpaths = ["tests"]
 addopts = "--tb=auto -ra --showlocals --no-success-flaky-report"
+markers = [
+    "network: tests requiring network connection",
+]
 
 [tool.towncrier]
 name = "tox"
--- a/tests/tox_env/python/virtual_env/package/test_package_cmd_builder.py
+++ b/tests/tox_env/python/virtual_env/package/test_package_cmd_builder.py
@@ -74,6 +74,7 @@ def test_install_pkg_via(tox_project: To
 
 
 @pytest.mark.usefixtures("enable_pip_pypi_access")
+@pytest.mark.network
 def test_build_wheel_external(tox_project: ToxProjectCreator, demo_pkg_inline: Path) -> None:
     ini = """
     [testenv]