diff --git a/openbr/plugins/meta.cpp b/openbr/plugins/meta.cpp
index 7a462f6..59b3cb3 100644
--- a/openbr/plugins/meta.cpp
+++ b/openbr/plugins/meta.cpp
@@ -588,57 +588,6 @@ static void _projectList(const Transform *transform, const TemplateList *src, Te
     transform->project(*src, *dst);
 }
 
-
-class TransformCopier : public ResourceMaker<Transform>
-{
-public:
-    Transform * basis;
-    TransformCopier(Transform * _basis)
-    {
-        basis = _basis;
-    }
-
-    virtual Transform *make() const
-    {
-        return basis->smartCopy();
-    }
-
-};
-
-class TimeInvariantWrapperTransform : public MetaTransform
-{
-public:
-    Resource<Transform> transformSource;
-
-    TimeInvariantWrapperTransform(Transform * basis) : transformSource(new TransformCopier(basis))
-    {
-        baseTransform = basis;
-    }
-
-    virtual void project(const Template &src, Template &dst) const
-    {
-        Transform * aTransform = transformSource.acquire();
-        aTransform->projectUpdate(src,dst);
-        transformSource.release(aTransform);
-    }
-
-
-    void project(const TemplateList &src, TemplateList &dst) const
-    {
-        Transform * aTransform = transformSource.acquire();
-        aTransform->projectUpdate(src,dst);
-        transformSource.release(aTransform);
-    }
-
-    void train(const TemplateList &data)
-    {
-        baseTransform->train(data);
-    }
-
-private:
-    Transform * baseTransform;
-};
-
 class DistributeTemplateTransform : public MetaTransform
 {
     Q_OBJECT
diff --git a/openbr/plugins/openbr_internal.h b/openbr/plugins/openbr_internal.h
index 7c992b6..8faa7d4 100644
--- a/openbr/plugins/openbr_internal.h
+++ b/openbr/plugins/openbr_internal.h
@@ -2,6 +2,7 @@
 #define __OPENBR_INTERNAL_H
 
 #include "openbr/openbr_plugin.h"
+#include "openbr/core/resource.h"
 
 namespace br
 {
@@ -97,6 +98,58 @@ protected:
     MetaTransform() : Transform(false) {}
 };
 
+
+class TransformCopier : public ResourceMaker<Transform>
+{
+public:
+    Transform * basis;
+    TransformCopier(Transform * _basis)
+    {
+        basis = _basis;
+    }
+
+    virtual Transform *make() const
+    {
+        return basis->smartCopy();
+    }
+
+};
+
+class TimeInvariantWrapperTransform : public MetaTransform
+{
+public:
+    Resource<Transform> transformSource;
+
+    TimeInvariantWrapperTransform(Transform * basis) : transformSource(new TransformCopier(basis))
+    {
+        baseTransform = basis;
+    }
+
+    virtual void project(const Template &src, Template &dst) const
+    {
+        Transform * aTransform = transformSource.acquire();
+        aTransform->projectUpdate(src,dst);
+        transformSource.release(aTransform);
+    }
+
+
+    void project(const TemplateList &src, TemplateList &dst) const
+    {
+        Transform * aTransform = transformSource.acquire();
+        aTransform->projectUpdate(src,dst);
+        transformSource.release(aTransform);
+    }
+
+    void train(const TemplateList &data)
+    {
+        baseTransform->train(data);
+    }
+
+private:
+    Transform * baseTransform;
+};
+
+
 /*!
  * \brief A MetaTransform that aggregates some sub-transforms
  */
@@ -116,10 +169,21 @@ public:
 
     virtual void project(const TemplateList &src, TemplateList &dst) const
     {
-        if (timeVarying()) qFatal("No const project defined for time-varying transform");
+        if (timeVarying()) {
+            if (!this->timeInvariantAlias) {
+                QMutexLocker lock(&aliasLock);
+                CompositeTransform * non_const = const_cast<CompositeTransform *>(this);
+                non_const->timeInvariantAlias = non_const->smartCopy();
+                non_const->timeInvariantAlias->setParent(non_const);
+                lock.unlock();
+            }
+            timeInvariantAlias->projectUpdate(src,dst);
+            return;
+        }
         _project(src, dst);
     }
 
+
     bool timeVarying() const { return isTimeVarying; }
 
     void init()
@@ -173,10 +237,13 @@ public:
 protected:
     bool isTimeVarying;
 
+    mutable QMutex aliasLock;
+    Transform * timeInvariantAlias;
+
     virtual void _project(const Template & src, Template & dst) const = 0;
     virtual void _project(const TemplateList & src, TemplateList & dst) const = 0;
 
-    CompositeTransform() : TimeVaryingTransform(false) {}
+    CompositeTransform() : TimeVaryingTransform(false) { timeInvariantAlias = NULL; }
 };
 
 }