diff --git a/include/layers/activation.hpp b/include/layers/activation.hpp
index 49787cf..b1aa3d7 100644
--- a/include/layers/activation.hpp
+++ b/include/layers/activation.hpp
@@ -30,7 +30,7 @@ class Activation {
      * @param activation Type of activation
      * @param length     Length of the input
      */
-    Activation(ActivationType activation, const int length);
+    Activation(CUDANet::Backend::IBackend* backend, ActivationType activation, const int length);
 
     /**
      * @brief Destroy the Activation object
diff --git a/src/layers/activation.cpp b/src/layers/activation.cpp
index 64f7590..892ce8f 100644
--- a/src/layers/activation.cpp
+++ b/src/layers/activation.cpp
@@ -6,13 +6,13 @@
 
 using namespace CUDANet::Layers;
 
-Activation::Activation(ActivationType activation, const int length)
-    : activationType(activation), length(length) {
+Activation::Activation(CUDANet::Backend::IBackend* backend, ActivationType activation, const int length)
+    : backend(backend), activationType(activation), length(length) {
 
 
     if (activationType == SOFTMAX) {
-      softmax_sum = CUDANet::Backend::Tensor({static_cast<size_t>(length)}, CUDANet::Backend::DType::FLOAT32, nullptr);
-      tensor_max = CUDANet::Backend::Tensor({static_cast<size_t>(length)}, CUDANet::Backend::DType::FLOAT32, nullptr);
+      softmax_sum = CUDANet::Backend::Tensor({static_cast<size_t>(length)}, CUDANet::Backend::DType::FLOAT32, backend);
+      tensor_max = CUDANet::Backend::Tensor({static_cast<size_t>(length)}, CUDANet::Backend::DType::FLOAT32, backend);
     }
 }
 
@@ -23,10 +23,10 @@ void Activation::activate(CUDANet::Backend::Tensor input) {
         backend->sigmoid(input);
         break;
     case ActivationType::RELU:
-        /* code */
+        backend->relu(input);
         break;
     case ActivationType::SOFTMAX:
-        /* code */
+        backend->softmax(input, tensor_max, softmax_sum);
         break;
     default:
         break;