diff --git a/src/daemon/MoneroDaemon.cpp b/src/daemon/MoneroDaemon.cpp
index 3c94ea4..a1d527f 100644
--- a/src/daemon/MoneroDaemon.cpp
+++ b/src/daemon/MoneroDaemon.cpp
@@ -194,6 +194,33 @@ namespace monero {
     unlockTime = MoneroUtils::reconcile(unlockTime, tx.unlockTime);
     numConfirmations = MoneroUtils::reconcile(numConfirmations, tx.numConfirmations);
 
+    // merge vins
+    if (!tx.vins.empty()) {
+      for (const shared_ptr<MoneroOutput>& merger : tx.vins) {
+        bool merged = false;
+        merger->tx = shared_ptr<MoneroTx>(this); // TODO: can this cause this* to be deleted prematurely?
+        for (const shared_ptr<MoneroOutput>& mergee : vins) {
+          //if (mergee.getKeyImage().getHex().equals(merger.getKeyImage().getHex())) {
+          if ((*mergee->keyImage)->hex == (*merger->keyImage)->hex) {
+            mergee->merge(*merger);
+            merged = true;
+            break;
+          }
+        }
+        if (!merged) vins.push_back(merger);
+      }
+    }
+
+    throw runtime_error("Not implemented");
+  }
+
+  void MoneroKeyImage::merge(const MoneroKeyImage& keyImage) {
+    cout << "MoneroKeyImage::merge()" << endl;
+    throw runtime_error("Not implemented");
+  }
+
+  void MoneroOutput::merge(const MoneroOutput& output) {
+    cout << "MoneroOutput::merge()" << endl;
     throw runtime_error("Not implemented");
   }
 
diff --git a/src/daemon/MoneroDaemon.h b/src/daemon/MoneroDaemon.h
index 87cbd3c..60dc825 100644
--- a/src/daemon/MoneroDaemon.h
+++ b/src/daemon/MoneroDaemon.h
@@ -156,6 +156,8 @@ namespace monero {
   struct MoneroKeyImage {
     boost::optional<string> hex;
     boost::optional<string> signature;
+
+    void merge(const MoneroKeyImage& keyImage);
   };
 
   /**
@@ -163,11 +165,13 @@ namespace monero {
    */
   struct MoneroOutput {
     shared_ptr<MoneroTx> tx;
-    boost::optional<MoneroKeyImage> keyImage;
+    boost::optional<shared_ptr<MoneroKeyImage>> keyImage;
     boost::optional<uint64_t> amount;
     boost::optional<uint32_t> index;
     vector<uint32_t> ringOutputIndices;
     boost::optional<string> stealthPublicKey;
+
+    void merge(const MoneroOutput& output);
   };
 }