diff --git a/src/ifcopenshell-python/test/conftest.py b/src/ifcopenshell-python/test/conftest.py
new file mode 100644
index 0000000000..2284b9ee79
--- /dev/null
+++ b/src/ifcopenshell-python/test/conftest.py
@@ -0,0 +1,7 @@
+def pytest_addoption(parser):
+    parser.addoption(
+        "--rule",
+        action="store",
+        default=None,
+        help="Only run test_rules.py fixtures whose filename contains this substring.",
+    )
diff --git a/src/ifcopenshell-python/test/test_rules.py b/src/ifcopenshell-python/test/test_rules.py
index ae981abf00..347d0320d8 100644
--- a/src/ifcopenshell-python/test/test_rules.py
+++ b/src/ifcopenshell-python/test/test_rules.py
@@ -1,6 +1,5 @@
 import glob
 import os
-import sys
 
 import pytest
 import tabulate
@@ -9,14 +8,18 @@ import ifcopenshell.express.rule_executor
 import ifcopenshell.validate
 
 
-@pytest.mark.parametrize(
-    "filename",
-    [
+def pytest_generate_tests(metafunc):
+    if "filename" not in metafunc.fixturenames:
+        return
+    rule = metafunc.config.getoption("--rule")
+    filenames = [
         fn
         for fn in glob.glob(os.path.join(os.path.dirname(__file__), "fixtures/rules/*.ifc"))
-        if len(sys.argv) < 2 or sys.argv[1] in os.path.basename(fn)
-    ],
-)
+        if not rule or rule in os.path.basename(fn)
+    ]
+    metafunc.parametrize("filename", filenames, ids=[os.path.basename(fn) for fn in filenames])
+
+
 def test_file(filename):
     base = os.path.basename(filename)
     file = ifcopenshell.open(filename)