diff --git a/src/noworkflow/now/models/dataflow_model.py b/src/noworkflow/now/models/dataflow_model.py
index 71d69df8..0bb6504b 100644
--- a/src/noworkflow/now/models/dataflow_model.py
+++ b/src/noworkflow/now/models/dataflow_model.py
@@ -23,8 +23,10 @@ class DataflowModel(Model):
     def __init__(self, trial=None, activation=None):
         super(DataflowModel, self).__init__()
         self.trial = None
+        self.trial_ref = None
         if trial is not None:
             self.trial = weakref.proxy(trial)
+            self.trial_ref = trial.id
         self.activation = None
         if activation is not None:
             self.activation = activation
@@ -36,12 +38,8 @@ def __init__(self, trial=None, activation=None):
 
     def _load_trial_and_activation(self):
         """Load trial or activation from trial/activation attributes"""
-        if self.activation is None and self.trial is None:
-            raise ValueError("Either activation or trial should be defined")
-        elif self.activation is not None:
-            self.trial = weakref.proxy(self.activation.trial)
-        elif self.trial is not None:
-            self.activation = self.trial.initial_activation
+        self.trial = self._get_trial()
+        self.activation = self.trial.initial_activation
 
     def export_text(self):
         """Export facts from trial as text"""
@@ -64,3 +62,17 @@ def _ipython_display_(self):
             "dot", "--format {}".format(self.format), self.export_text()
         )
         display(obj)
+
+    def _get_trial(self):
+        if self.trial is not None:
+            try:
+                self.trial.id  # just verifies the proxy is alive
+                return self.trial
+            except ReferenceError:
+                pass
+
+        if self.trial_ref is not None:
+            from ..persistence.models.trial import Trial
+            return Trial(self.trial_ref)
+
+        raise ValueError("Either activation or trial should be defined")
diff --git a/src/noworkflow/now/models/dependency_graph/config.py b/src/noworkflow/now/models/dependency_graph/config.py
index 40cf37f7..174c5c64 100644
--- a/src/noworkflow/now/models/dependency_graph/config.py
+++ b/src/noworkflow/now/models/dependency_graph/config.py
@@ -43,7 +43,7 @@ def __init__(self):
         self.hide_not_code = False
         self.hide_func = False
         self.max_depth = float("inf")
-        self.mode = "simulation"
+        self.mode = "coarseGrain"
 
     @classmethod
     def create_arguments(cls, add_arg, mode="coarseGrain"):
diff --git a/src/noworkflow/tests/__init__.py b/src/noworkflow/tests/__init__.py
index 52ffea34..55db4c30 100644
--- a/src/noworkflow/tests/__init__.py
+++ b/src/noworkflow/tests/__init__.py
@@ -29,6 +29,7 @@
 from .dependency import TestClusterizer, TestClusterizerConfig
 from .dependency import TestProspectiveClusterizer
 from .dependency import TestActivationClusterizer, TestDependencyClusterizer
+from .dependency import TestDataflowModel
 from .cross_version_test import TestCrossVersion
 
 from ..now.persistence.models import ORDER
@@ -76,6 +77,7 @@
 dataflow.addTests(loader.loadTestsFromTestCase(TestActivationClusterizer))
 dataflow.addTests(loader.loadTestsFromTestCase(TestProspectiveClusterizer))
 dataflow.addTests(loader.loadTestsFromTestCase(TestClusterizerConfig))
+dataflow.addTests(loader.loadTestsFromTestCase(TestDataflowModel))
 
 
 def load_tests(loader, tests, pattern):
diff --git a/src/noworkflow/tests/dependency/__init__.py b/src/noworkflow/tests/dependency/__init__.py
index d9c2dfbe..1428d6d0 100644
--- a/src/noworkflow/tests/dependency/__init__.py
+++ b/src/noworkflow/tests/dependency/__init__.py
@@ -11,6 +11,7 @@
 from .test_dependency_clusterizer import TestDependencyClusterizer
 from .test_activation_clusterizer import TestActivationClusterizer
 from .test_prospective_clusterizer import TestProspectiveClusterizer
+from .test_dataflow_model import TestDataflowModel
 from .test_clusterizer_config import TestClusterizerConfig
 
 __all__ = [
@@ -19,4 +20,5 @@
     "TestActivationClusterizer",
     "TestProspectiveClusterizer",
     "TestClusterizerConfig",
+    "TestDataflowModel"
 ]
diff --git a/src/noworkflow/tests/dependency/test_dataflow_model.py b/src/noworkflow/tests/dependency/test_dataflow_model.py
new file mode 100644
index 00000000..c1b76ba1
--- /dev/null
+++ b/src/noworkflow/tests/dependency/test_dataflow_model.py
@@ -0,0 +1,26 @@
+import gc
+
+from ...now.persistence.models import Trial
+from ..collection_testcase import CollectionTestCase
+
+
+class TestDataflowModel(CollectionTestCase):
+    def test_export_text_reloads_trial_after_weakref_dies(self):
+        self.script("# script.py\n"
+                    "x = 1\n"
+                    "y = x + 2\n"
+                    "print(y)\n")
+        self.clean_execution()
+
+        trial = Trial()
+        trial_ref = trial.id
+
+        trial = Trial(trial_ref)
+        dot = trial.dot
+
+        del trial
+        gc.collect()
+
+        text = dot.export_text()
+
+        self.assertIn("digraph", text)