diff --git a/tests/fixtures.py b/tests/fixtures.py
index dee13889..a6673d56 100644
--- a/tests/fixtures.py
+++ b/tests/fixtures.py
@@ -80,16 +80,6 @@ def get_viv_extractor(path):
     return capa.features.extractors.viv.VivisectFeatureExtractor(vw, path)
 
 
-@lru_cache
-def get_lancelot_extractor(path):
-    import capa.features.extractors.lancelot
-
-    with open(path, "rb") as f:
-        buf = f.read()
-
-    return capa.features.extractors.lancelot.LancelotFeatureExtractor(buf)
-
-
 @lru_cache()
 def extract_file_features(extractor):
     features = collections.defaultdict(set)
@@ -437,7 +427,7 @@ def do_test_feature_count(get_extractor, sample, scope, feature, expected):
 
 def get_extractor(path):
     if sys.version_info >= (3, 0):
-        extractor = get_lancelot_extractor(path)
+        raise RuntimeError("no supported py3 backends yet")
     else:
         extractor = get_viv_extractor(path)
 
diff --git a/tests/test_freeze.py b/tests/test_freeze.py
index cbd31ad4..1cc4e27a 100644
--- a/tests/test_freeze.py
+++ b/tests/test_freeze.py
@@ -5,7 +5,9 @@
 # Unless required by applicable law or agreed to in writing, software distributed under the License
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
+import sys
 
+import pytest
 import textwrap
 
 from fixtures import *
@@ -163,6 +165,7 @@ def test_serialize_features():
     roundtrip_feature(capa.features.file.Import("#11"))
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_freeze_sample(tmpdir, z9324d_extractor):
     # tmpdir fixture handles cleanup
     o = tmpdir.mkdir("capa").join("test.frz").strpath
@@ -170,6 +173,7 @@ def test_freeze_sample(tmpdir, z9324d_extractor):
     assert capa.features.freeze.main([path, o, "-v"]) == 0
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_freeze_load_sample(tmpdir, z9324d_extractor):
     o = tmpdir.mkdir("capa").join("test.frz")
 
diff --git a/tests/test_main.py b/tests/test_main.py
index 9125c123..f1b48b2e 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -5,18 +5,20 @@
 # Unless required by applicable law or agreed to in writing, software distributed under the License
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
+import sys
 
+import pytest
 import textwrap
 
-from fixtures import *
-
 import capa.main
 import capa.rules
 import capa.engine
 import capa.features
 from capa.engine import *
 
+from fixtures import *
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_main(z9324d_extractor):
     # tests rules can be loaded successfully and all output modes
     path = z9324d_extractor.path
@@ -26,6 +28,7 @@ def test_main(z9324d_extractor):
     assert capa.main.main([path]) == 0
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_main_single_rule(z9324d_extractor, tmpdir):
     # tests a single rule can be loaded successfully
     RULE_CONTENT = textwrap.dedent(
@@ -44,6 +47,7 @@ def test_main_single_rule(z9324d_extractor, tmpdir):
     assert capa.main.main([path, "-v", "-r", rule_file.strpath,]) == 0
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_main_shellcode(z499c2_extractor):
     path = z499c2_extractor.path
     assert capa.main.main([path, "-vv", "-f", "sc32"]) == 0
@@ -98,6 +102,7 @@ def test_ruleset():
     assert len(rules.basic_block_rules) == 1
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_match_across_scopes_file_function(z9324d_extractor):
     rules = capa.rules.RuleSet(
         [
@@ -161,6 +166,7 @@ def test_match_across_scopes_file_function(z9324d_extractor):
     assert ".text section and install service" in capabilities
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_match_across_scopes(z9324d_extractor):
     rules = capa.rules.RuleSet(
         [
@@ -223,6 +229,7 @@ def test_match_across_scopes(z9324d_extractor):
     assert "kill thread program" in capabilities
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_subscope_bb_rules(z9324d_extractor):
     rules = capa.rules.RuleSet(
         [
@@ -247,6 +254,7 @@ def test_subscope_bb_rules(z9324d_extractor):
     assert "test rule" in capabilities
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_byte_matching(z9324d_extractor):
     rules = capa.rules.RuleSet(
         [
@@ -269,6 +277,7 @@ def test_byte_matching(z9324d_extractor):
     assert "byte match test" in capabilities
 
 
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason="vivsect only works on py2")
 def test_count_bb(z9324d_extractor):
     rules = capa.rules.RuleSet(
         [