diff --git a/Hamiltonian.jl b/Hamiltonian.jl
index b5fef55..324346c 100644
--- a/Hamiltonian.jl
+++ b/Hamiltonian.jl
@@ -1,5 +1,5 @@
 include("common.jl")
-using TensorOperations, KrylovKit, LinearAlgebra, CUDA, cuTENSOR
+using TensorOperations, KrylovKit, LinearAlgebra, CUDA, cuTENSOR, NVTX
 
 @enum Hamiltonian_backend cpu_tensor gpu_cutensor