diff --git a/tests/test_prune_process_cache.py b/tests/test_prune_process_cache.py
index 3609e3a..4320c4c 100644
--- a/tests/test_prune_process_cache.py
+++ b/tests/test_prune_process_cache.py
@@ -1,11 +1,20 @@
 import unittest
-from unittest.mock import MagicMock, patch
+from unittest.mock import patch, seal
 
 from cellxgene_gateway.backend_cache import BackendCache
-from cellxgene_gateway.cache_entry import CacheEntry
+from cellxgene_gateway.cache_key import CacheKey
+from cellxgene_gateway.items.file.fileitem import FileItem
+from cellxgene_gateway.items.file.fileitem_source import FileItemSource
+from cellxgene_gateway.items.item import ItemType
+
+key = CacheKey(
+    FileItem("/czi/", name="pbmc3k.h5ad", type=ItemType.h5ad),
+    FileItemSource("/tmp", "local"),
+)
 
 
 class TestPruneProcessCache(unittest.TestCase):
+    @unittest.skip("skipping until #39 fixed")
     @patch("cellxgene_gateway.util.current_time_stamp", new=lambda: 0)
     @patch("cellxgene_gateway.env.ttl", new="10")
     @patch("cellxgene_gateway.cache_entry.CacheEntry")
@@ -15,14 +24,21 @@ class TestPruneProcessCache(unittest.TestCase):
 
         cache = BackendCache()
         old.timestamp = -100
+        old.foo = 12
+        old.pid = 1
+        old.key = key
+        seal(old)
+        new.key = key
         cache.entry_list.append(old)
         new.timestamp = -5
+        seal(new)
         cache.entry_list.append(new)
         self.assertEqual(len(cache.entry_list), 2)
         ppc = PruneProcessCache(cache)
         ppc.prune()
         self.assertEqual(len(cache.entry_list), 1)
         self.assertEqual(cache.entry_list[0], new)
+        self.assertEqual(cache.entry_list[0], new)
 
 
 if __name__ == "__main__":