diff --git a/src/Network/NeuralNetwork.cpp b/src/Network/NeuralNetwork.cpp
index a51d704c1d6af870ce4e993e050191638ec21b27..d48bfa27bbec4d2e209be998820792bbf75a5299 100644
--- a/src/Network/NeuralNetwork.cpp
+++ b/src/Network/NeuralNetwork.cpp
@@ -506,7 +506,7 @@ namespace lib4neuro {
         return this->connection_list->size() - 1;
     }
 
-    void
+    size_t
     NeuralNetwork::add_connection_constant(size_t n1_idx, size_t n2_idx, double weight) {
 
         ConnectionFunctionConstant *con_weight_u1u2 = new ConnectionFunctionConstant( weight );
@@ -517,6 +517,8 @@ namespace lib4neuro {
         this->add_inward_connection(n2_idx, n1_idx, conn_idx);
 
         this->layers_analyzed = false;
+
+        return conn_idx;
     }
 
     void NeuralNetwork::add_existing_connection(size_t n1_idx, size_t n2_idx, size_t connection_idx,
diff --git a/src/Network/NeuralNetwork.h b/src/Network/NeuralNetwork.h
index 8edb9e876a526f4807c9756cf4795118a5eb76a1..00d189214fd92461fd6a0b8d6cbcb58dc5675c72 100644
--- a/src/Network/NeuralNetwork.h
+++ b/src/Network/NeuralNetwork.h
@@ -279,7 +279,7 @@ namespace lib4neuro {
          * @param n2_idx
          * @param weight
          */
-        LIB4NEURO_API void add_connection_constant(size_t n1_idx, size_t n2_idx, double weight);
+        LIB4NEURO_API size_t add_connection_constant(size_t n1_idx, size_t n2_idx, double weight);
 
         /**
          * Take the existing connection with index 'connection_idx' in 'parent_network' and adds it to the structure of this