diff --git a/extras/Hadrons/Global.cc b/extras/Hadrons/Global.cc
index 942a4243..9a90a08c 100644
--- a/extras/Hadrons/Global.cc
+++ b/extras/Hadrons/Global.cc
@@ -67,3 +67,10 @@ std::string Hadrons::typeName(const std::type_info *info)
     
     return name;
 }
+
+// default writers/readers /////////////////////////////////////////////////////
+#ifdef HAVE_HDF5
+const std::string Hadrons::resultFileExt = "h5";
+#else
+const std::string Hadrons::resultFileExt = "xml";
+#endif
diff --git a/extras/Hadrons/Global.hpp b/extras/Hadrons/Global.hpp
index 274e1934..fc069ed6 100644
--- a/extras/Hadrons/Global.hpp
+++ b/extras/Hadrons/Global.hpp
@@ -167,14 +167,19 @@ std::string typeName(void)
 }
 
 // default writers/readers
+extern const std::string resultFileExt;
+
 #ifdef HAVE_HDF5
-typedef Hdf5Reader CorrReader;
-typedef Hdf5Writer CorrWriter;
+typedef Hdf5Reader ResultReader;
+typedef Hdf5Writer ResultWriter;
 #else
-typedef XmlReader CorrReader;
-typedef XmlWriter CorrWriter;
+typedef XmlReader ResultReader;
+typedef XmlWriter ResultWriter;
 #endif
 
+#define RESULT_FILE_NAME(name) \
+name + "." + std::to_string(vm().getTrajectory()) + "." + resultFileExt
+
 END_HADRONS_NAMESPACE
 
 #include <Grid/Hadrons/Exceptions.hpp>
diff --git a/extras/Hadrons/Modules/MContraction/Baryon.hpp b/extras/Hadrons/Modules/MContraction/Baryon.hpp
index 625c7108..8966d95b 100644
--- a/extras/Hadrons/Modules/MContraction/Baryon.hpp
+++ b/extras/Hadrons/Modules/MContraction/Baryon.hpp
@@ -122,7 +122,7 @@ void TBaryon<FImpl1, FImpl2, FImpl3>::execute(void)
                  << " quarks '" << par().q1 << "', '" << par().q2 << "', and '"
                  << par().q3 << "'" << std::endl;
     
-    CorrWriter writer(par().output);
+    ResultWriter writer(RESULT_FILE_NAME(par().output));
     auto       &q1 = envGet(PropagatorField1, par().q1);
     auto       &q2 = envGet(PropagatorField2, par().q2);
     auto       &q3 = envGet(PropagatorField3, par().q2);
diff --git a/extras/Hadrons/Modules/MContraction/DiscLoop.hpp b/extras/Hadrons/Modules/MContraction/DiscLoop.hpp
index 3d08f0eb..539abbbb 100644
--- a/extras/Hadrons/Modules/MContraction/DiscLoop.hpp
+++ b/extras/Hadrons/Modules/MContraction/DiscLoop.hpp
@@ -119,7 +119,7 @@ void TDiscLoop<FImpl>::execute(void)
                  << "' using '" << par().q_loop << "' with " << par().gamma 
                  << " insertion." << std::endl;
 
-    CorrWriter            writer(par().output);
+    ResultWriter          writer(RESULT_FILE_NAME(par().output));
     auto                  &q_loop = envGet(PropagatorField, par().q_loop);
     Gamma                 gamma(par().gamma);
     std::vector<TComplex> buf;
diff --git a/extras/Hadrons/Modules/MContraction/Gamma3pt.hpp b/extras/Hadrons/Modules/MContraction/Gamma3pt.hpp
index 68701aeb..b4327a13 100644
--- a/extras/Hadrons/Modules/MContraction/Gamma3pt.hpp
+++ b/extras/Hadrons/Modules/MContraction/Gamma3pt.hpp
@@ -153,7 +153,7 @@ void TGamma3pt<FImpl1, FImpl2, FImpl3>::execute(void)
 
     // Initialise variables. q2 and q3 are normal propagators, q1 may be 
     // sink smeared.
-    CorrWriter            writer(par().output);
+    ResultWriter          writer(RESULT_FILE_NAME(par().output));
     auto                  &q1 = envGet(SlicedPropagator1, par().q1);
     auto                  &q2 = envGet(PropagatorField2, par().q2);
     auto                  &q3 = envGet(PropagatorField2, par().q3);
diff --git a/extras/Hadrons/Modules/MContraction/Meson.hpp b/extras/Hadrons/Modules/MContraction/Meson.hpp
index 5cf504e3..0197534d 100644
--- a/extras/Hadrons/Modules/MContraction/Meson.hpp
+++ b/extras/Hadrons/Modules/MContraction/Meson.hpp
@@ -172,7 +172,7 @@ void TMeson<FImpl1, FImpl2>::execute(void)
                  << " quarks '" << par().q1 << "' and '" << par().q2 << "'"
                  << std::endl;
     
-    CorrWriter             writer(par().output);
+    ResultWriter           writer(RESULT_FILE_NAME(par().output));
     std::vector<TComplex>  buf;
     std::vector<Result>    result;
     Gamma                  g5(Gamma::Algebra::Gamma5);
diff --git a/extras/Hadrons/Modules/MContraction/WeakHamiltonianEye.cc b/extras/Hadrons/Modules/MContraction/WeakHamiltonianEye.cc
index b79c09e7..1d257fc7 100644
--- a/extras/Hadrons/Modules/MContraction/WeakHamiltonianEye.cc
+++ b/extras/Hadrons/Modules/MContraction/WeakHamiltonianEye.cc
@@ -104,7 +104,7 @@ void TWeakHamiltonianEye::execute(void)
                  << par().q2 << ", '" << par().q3 << "' and '" << par().q4 
                  << "'." << std::endl;
 
-    CorrWriter             writer(par().output);
+    ResultWriter           writer(RESULT_FILE_NAME(par().output));
     auto                   &q1 = envGet(SlicedPropagator, par().q1);
     auto                   &q2 = envGet(PropagatorField, par().q2);
     auto                   &q3 = envGet(PropagatorField, par().q3);
diff --git a/extras/Hadrons/Modules/MContraction/WeakHamiltonianNonEye.cc b/extras/Hadrons/Modules/MContraction/WeakHamiltonianNonEye.cc
index e66b6ee7..2ad2e7dc 100644
--- a/extras/Hadrons/Modules/MContraction/WeakHamiltonianNonEye.cc
+++ b/extras/Hadrons/Modules/MContraction/WeakHamiltonianNonEye.cc
@@ -104,7 +104,7 @@ void TWeakHamiltonianNonEye::execute(void)
                  << par().q2 << ", '" << par().q3 << "' and '" << par().q4 
                  << "'." << std::endl;
     
-    CorrWriter            writer(par().output);
+    ResultWriter          writer(RESULT_FILE_NAME(par().output));
     auto                  &q1 = envGet(PropagatorField, par().q1);
     auto                  &q2 = envGet(PropagatorField, par().q2);
     auto                  &q3 = envGet(PropagatorField, par().q3);
diff --git a/extras/Hadrons/Modules/MContraction/WeakNeutral4ptDisc.cc b/extras/Hadrons/Modules/MContraction/WeakNeutral4ptDisc.cc
index e0a00472..2c94b2ba 100644
--- a/extras/Hadrons/Modules/MContraction/WeakNeutral4ptDisc.cc
+++ b/extras/Hadrons/Modules/MContraction/WeakNeutral4ptDisc.cc
@@ -104,7 +104,7 @@ void TWeakNeutral4ptDisc::execute(void)
                  << par().q2 << ", '" << par().q3 << "' and '" << par().q4 
                  << "'." << std::endl;
 
-    CorrWriter            writer(par().output);
+    ResultWriter          writer(RESULT_FILE_NAME(par().output));
     auto                  &q1 = envGet(PropagatorField, par().q1);
     auto                  &q2 = envGet(PropagatorField, par().q2);
     auto                  &q3 = envGet(PropagatorField, par().q3);
diff --git a/extras/Hadrons/Modules/MScalar/ChargedProp.cc b/extras/Hadrons/Modules/MScalar/ChargedProp.cc
index da82617f..1470f1ad 100644
--- a/extras/Hadrons/Modules/MScalar/ChargedProp.cc
+++ b/extras/Hadrons/Modules/MScalar/ChargedProp.cc
@@ -133,7 +133,7 @@ void TChargedProp::execute(void)
         LOG(Message) << "Saving zero-momentum projection to '"
                      << filename << "'..." << std::endl;
         
-        CorrWriter            writer(filename);
+        ResultWriter          writer(RESULT_FILE_NAME(par().output));
         std::vector<TComplex> vecBuf;
         std::vector<Complex>  result;