diff --git a/loopy/kernel/__init__.py b/loopy/kernel/__init__.py
index e5305b703a4f03adcc886b03dece75c9273c4ca2..dccaca2ec104a4749289f7cd89c491292f618e3d 100644
--- a/loopy/kernel/__init__.py
+++ b/loopy/kernel/__init__.py
@@ -1400,17 +1400,35 @@ class LoopKernel(ImmutableRecordWithoutPickling):
 
         result.pop("cache_manager", None)
 
-        return result
+        # make sure that kernels are pickled with a cached hash key in place
+        from loopy.tools import LoopyKeyBuilder
+        LoopyKeyBuilder()(self)
+
+        return (result, self._pytools_persistent_hash_digest)
 
     def __setstate__(self, state):
+        attribs, p_hash_digest = state
+
         new_fields = set()
 
-        for k, v in six.iteritems(state):
+        for k, v in six.iteritems(attribs):
             setattr(self, k, v)
             new_fields.add(k)
 
         self.register_fields(new_fields)
 
+        if 0:
+            # {{{ check that 'reconstituted' object has same hash
+
+            from loopy.tools import LoopyKeyBuilder
+            LoopyKeyBuilder()(self)
+
+            assert p_hash_digest == self._pytools_persistent_hash_digest
+
+            # }}}
+        else:
+            self._pytools_persistent_hash_digest = p_hash_digest
+
         from loopy.kernel.tools import SetOperationCacheManager
         self.cache_manager = SetOperationCacheManager()
         self._kernel_executor_cache = {}
diff --git a/loopy/version.py b/loopy/version.py
index 4c6dfbcc22c0ea38668c663eb858161471a3999a..8516ce006bde8b8616172a72a766ec86dfcd44f1 100644
--- a/loopy/version.py
+++ b/loopy/version.py
@@ -32,4 +32,4 @@ except ImportError:
 else:
     _islpy_version = islpy.version.VERSION_TEXT
 
-DATA_MODEL_VERSION = "v62-islpy%s" % _islpy_version
+DATA_MODEL_VERSION = "v63-islpy%s" % _islpy_version