diff --git a/src/validate_encoder_decoder.cu b/src/validate_encoder_decoder.cu
index ec9951ec..15159ba6 100644
--- a/src/validate_encoder_decoder.cu
+++ b/src/validate_encoder_decoder.cu
@@ -1,7 +1,7 @@
 #include "marian.h"
 #include "mnist.h"
 #include "vocab.h"
-#include <assert.h>
+#include "optimizers.h"
 
 using namespace marian;
 using namespace keywords;
@@ -194,24 +194,15 @@ int main(int argc, char** argv) {
   std::cerr << "Printing the computation graph..." << std::endl;
   std::cout << g.graphviz() << std::endl;
 
-  std::cerr << "Running the forward step..." << std::endl;
-  g.forward(batch_size);
-  std::cerr << "Running the backward step..." << std::endl;
-  g.backward();
-  std::cerr << "Done." << std::endl;
-
-  std::cerr << g["cost"].val().Debug() << std::endl;
-
-#if 0
-  std::cerr << g["X0"].val().Debug() << std::endl;
-  std::cerr << g["Y0"].val().Debug() << std::endl;
-  std::cerr << g["Whh"].grad().Debug() << std::endl;
-  std::cerr << g["bh"].grad().Debug() << std::endl;
-  std::cerr << g["Why"].grad().Debug() << std::endl;
-  std::cerr << g["by"].grad().Debug() << std::endl;
-  std::cerr << g["Wxh"].grad().Debug() << std::endl;
-  std::cerr << g["h0"].grad().Debug() << std::endl;
-#endif
+  std::cerr << "Training..." << std::endl;
+  Adam opt;
+  int num_epochs = 20;
+  for(size_t epoch = 0; epoch < num_epochs; ++epoch) {
+    opt(g, batch_size); // Full batch for now.
+    std::cerr << "Epoch " << epoch << ": "
+              << "Loss = " << g["cost"].val()[0]
+              << std::endl;
+  }
 
   return 0;
 }