diff --git a/onnxscript/converter_test.py b/onnxscript/converter_test.py
index 2e12222ee..6036641ff 100644
--- a/onnxscript/converter_test.py
+++ b/onnxscript/converter_test.py
@@ -17,6 +17,7 @@
 import numpy as np
 import onnx
 import onnxruntime as ort
+import pytest
 from onnxruntime.capi.onnxruntime_pybind11_state import (
     Fail,
     InvalidArgument,
@@ -270,7 +271,10 @@ def test_renaming(self):
 
         self.validate_save(renaming, shape_inference=False)
 
-    @unittest.skip(reason="TypeError: val must be numeric not <class 'NoneType'>")
+    @pytest.mark.xfail(
+        strict=True,
+        reason="default_opset must be specified in script for functions that do not contain any use of an ONNX op",
+    )
     def test_opt_output(self):
         from onnxscript.tests.models import opt_output
 
diff --git a/onnxscript/function_libs/torch_lib/graph_building_test.py b/onnxscript/function_libs/torch_lib/graph_building_test.py
index d38bb52d5..ab8b4bc8f 100644
--- a/onnxscript/function_libs/torch_lib/graph_building_test.py
+++ b/onnxscript/function_libs/torch_lib/graph_building_test.py
@@ -11,11 +11,9 @@
 import onnxscript.testing
 from onnxscript import FLOAT, evaluator
 from onnxscript import opset18 as op
-from onnxscript._internal import version_utils
 from onnxscript.function_libs.torch_lib import graph_building, ops
 
 
-@unittest.skipIf(version_utils.torch_older_than("2.0"), "torchscript in 1.13 not supported")
 class TestTorchScriptTracingEvaluator(unittest.TestCase):
     def setUp(self):
         self.opset_version = 18
diff --git a/onnxscript/tests/functions/onnxfns1A_test.py b/onnxscript/tests/functions/onnxfns1A_test.py
index 2d3b6287f..09302a634 100644
--- a/onnxscript/tests/functions/onnxfns1A_test.py
+++ b/onnxscript/tests/functions/onnxfns1A_test.py
@@ -1,6 +1,5 @@
 import unittest
 
-import onnx
 import pytest
 
 from onnxscript.tests.common import onnx_script_test_case
@@ -16,51 +15,27 @@ def setUpClass(cls):
     def test_onnxfns_relu(self):
         self.run_onnx_test(onnxfns1A.Relu)
 
-    @unittest.skipIf(
-        not hasattr(onnx.FunctionProto, "attribute_proto"),
-        reason="ONNX 1.13 does not support default values",
-    )
     def test_onnxfns_selu(self):
         self.run_onnx_test(onnxfns1A.Selu)
 
-    @unittest.skipIf(
-        not hasattr(onnx.FunctionProto, "attribute_proto"),
-        reason="current onnx does not support default values",
-    )
     def test_onnxfns_elu(self):
         self.run_onnx_test(onnxfns1A.Elu)
 
     def test_onnxfns_elu05(self):
         self.run_onnx_test(onnxfns1A.Elu05)
 
-    @unittest.skipIf(
-        not hasattr(onnx.FunctionProto, "attribute_proto"),
-        reason="ONNX 1.13 does not support default values",
-    )
     def test_onnxfns_thresholded_relu(self):
         self.run_onnx_test(onnxfns1A.ThresholdedRelu)
 
-    @unittest.skipIf(
-        not hasattr(onnx.FunctionProto, "attribute_proto"),
-        reason="ONNX 1.13 does not support default values",
-    )
     def test_onnxfns_leaky_relu(self):
         self.run_onnx_test(onnxfns1A.LeakyRelu)
 
     def test_onnxfns_prelu(self):
         self.run_onnx_test(onnxfns1A.PRelu)
 
-    @unittest.skipIf(
-        not hasattr(onnx.FunctionProto, "attribute_proto"),
-        reason="current onnx does not support default values",
-    )
     def test_onnxfns_hard_sigmoid(self):
         self.run_onnx_test(onnxfns1A.HardSigmoid)
 
-    @unittest.skipIf(
-        not hasattr(onnx.FunctionProto, "attribute_proto"),
-        reason="current onnx does not support default values",
-    )
     def test_onnxfns_shrink(self):
         self.run_onnx_test(onnxfns1A.Shrink)
 
@@ -71,7 +46,8 @@ def test_onnxfns_hard_softsign(self):
         self.run_onnx_test(onnxfns1A.Softsign)
 
     @pytest.mark.xfail(
-        reason="Clip has optional input min and max. Need to find out how to pass default min and max to the test case executor."
+        strict=True,
+        reason="Clip has optional input min and max. Need to find out how to pass default min and max to the test case executor.",
     )
     def test_onnxfns_hard_clip(self):
         self.run_onnx_test(onnxfns1A.Clip)
diff --git a/onnxscript/tests/functions/onnxfns_test.py b/onnxscript/tests/functions/onnxfns_test.py
index d9bcd80ec..68ae2e3b8 100644
--- a/onnxscript/tests/functions/onnxfns_test.py
+++ b/onnxscript/tests/functions/onnxfns_test.py
@@ -5,8 +5,6 @@
 
 import unittest
 
-import onnx
-
 from onnxscript.tests.common import onnx_script_test_case
 from onnxscript.tests.models import onnxfns1
 
@@ -57,10 +55,6 @@ def test_onnxfns_hard_softplus(self):
     def test_onnxfns_hard_softsign(self):
         self.run_onnx_test(onnxfns1.Softsign)
 
-    @unittest.skipIf(
-        not hasattr(onnx.FunctionProto, "attribute_proto"),
-        reason="current onnx does not support default values",
-    )
     def test_onnxfns_hard_clip(self):
         self.run_onnx_test(
             onnxfns1.Clip,
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 2292af13e..218ec9715 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,7 +1,7 @@
 setuptools>=61.0.0
 numpy
 onnx-weekly==1.15.0.dev20230807
-onnxruntime
+onnxruntime>=1.15.1
 typing_extensions
 
 # Docs site