diff --git a/bench/Makefile.am b/bench/Makefile.am
index 88575a5..39ce3c3 100644
--- a/bench/Makefile.am
+++ b/bench/Makefile.am
@@ -16,3 +16,7 @@ else
 test_main_LDADD += @LIBCTF_LD_LIBRARY_PATH@/libctf.a
 endif
 
+if WITH_CUDA
+test_main_CXXFLAGS = $(CUDA_CXXFLAGS)
+test_main_LDADD += $(CUDA_LDFLAGS)
+endif
diff --git a/configure.ac b/configure.ac
index cabeca4..cb25ce6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -26,7 +26,6 @@ AC_ARG_ENABLE([docs],
                               [Enable building docs])],
               [build_docs=YES], [build_docs=NO])
 
-
 dnl LIBGC library options
 AC_ARG_WITH(libctf-prefix,
             AS_HELP_STRING([--with-libctf-prefix=path],
@@ -50,6 +49,15 @@ AC_ARG_WITH(dgemm,
             [with_dgemm=NO],
             [with_dgemm=YES])
 
+AC_ARG_ENABLE([cuda],
+              [AS_HELP_STRING([--enable-cuda],
+                              [Build with cuda])],
+                              [WITH_CUDA=yes],
+                              [WITH_CUDA=no])
+AC_ARG_VAR([NVCC], [Path to the nvidia cuda compiler.])
+AC_ARG_VAR([CUDA_LDFLAGS], [LDFLAGS to find libraries -lcuda and -lcudart.])
+AC_ARG_VAR([CUDA_CXXFLAGS], [CXXFLAGS to find the CUDA headers])
+
 
 
 dnl -----------------------------------------------------------------------
@@ -124,6 +132,21 @@ else
                   [AC_MSG_ERROR([no ctf.hpp])])
 fi
 
+dnl CUDA NVIDIA -----------------------------------------------------------
+
+AM_CONDITIONAL([WITH_CUDA], [test x${WITH_CUDA} = xyes])
+if test x${WITH_CUDA} = xyes; then
+  AC_MSG_RESULT([
+                     CUDA SUPPORT IS ENABLED
+                     -----------------------
+  ])
+  AC_CHECK_PROGS([NVCC], [nvcc])
+  AC_SUBST([CUDA_LDFLAGS])
+  AC_DEFINE([HAVE_CUDA],1,[Wether we are using CUDA])
+  # TODO: make sure to find cuda and cudart
+  # AC_SEARCH_LIBS([cudaMalloc], [cuda cudart], [FOUND_CUDA=yes])
+fi
+
 dnl -----------------------------------------------------------------------
 dnl Docs
 if test x${build_docs} = xYES; then
diff --git a/cuda.nix b/cuda.nix
new file mode 100644
index 0000000..cf5e454
--- /dev/null
+++ b/cuda.nix
@@ -0,0 +1,19 @@
+{pkgs}:
+{
+
+  shellHook = ''
+    export NVCC=${pkgs.cudatoolkit}/bin/nvcc
+
+    export CUDA_ROOT_PATH=${pkgs.cudatoolkit}
+    export CUDA_CXXFLAGS="-I${pkgs.openmpi.out}/include -I$CUDA_ROOT_PATH/include"
+
+    # cudart
+    export CUDA_LIB_PATH=${pkgs.cudatoolkit.lib}
+    export CUDA_OUT_PATH=${pkgs.cudatoolkit.out}
+
+    # in here is libcuda
+    export CUDA_X11LIB="${pkgs.linuxPackages.nvidia_x11}/lib"
+    export CUDA_LDFLAGS="-L$CUDA_X11LIB -L$CUDA_ROOT_PATH/lib -L$CUDA_LIB_PATH/lib -lcuda -lcudart"
+  '';
+
+}
diff --git a/shell.nix b/shell.nix
index 4db21e5..5f4aa06 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,4 +1,9 @@
-{ compiler ? "gcc", pkgs ? import <nixpkgs> {} , with-mkl ? false, docs ? true }:
+{ compiler ? "gcc"
+, pkgs ? import <nixpkgs> {} 
+, with-mkl ? false
+, cuda ? false
+, docs ? true
+}:
 
 let
 
@@ -8,10 +13,13 @@ let
 
   openblas = import ./etc/nix/openblas.nix { inherit pkgs; }; 
 
+  cuda-pkg = if cuda then (import ./cuda.nix { inherit pkgs; }) else {};
+
 in
 
 pkgs.mkShell rec {
 
+
   compiler-pkg
     = if compiler    == "gcc11" then pkgs.gcc11
     else if compiler == "gcc10" then pkgs.gcc10
@@ -50,7 +58,7 @@ pkgs.mkShell rec {
     = with pkgs; [
 
         coreutils
-        git
+        git vim
 
         openmpi
         llvmPackages.openmp
@@ -74,7 +82,7 @@ pkgs.mkShell rec {
   LD = "${compiler-pkg}/bin/ld";
 
   shellHook
-    = #(if with-mkl then mkl.shellHook else openblas.shellHook)
+    =
     ''
     export OMPI_CXX=${CXX}
     export OMPI_CC=${CC}
@@ -82,6 +90,7 @@ pkgs.mkShell rec {
     CC=${CC}
     LD=${LD}
     ''
+    + (if cuda then cuda-pkg.shellHook else "")
     ;
 
 }
diff --git a/src/Makefile.am b/src/Makefile.am
index 468c05a..cb46935 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,9 +1,23 @@
 AUTOMAKE_OPTIONS = subdir-objects
 include $(top_srcdir)/atrip.mk
 
-AM_CXXFLAGS = $(CTF_CPPFLAGS)
+AM_CXXFLAGS = $(CTF_CPPFLAGS) -fmax-errors=1
 
 lib_LIBRARIES = libatrip.a
 
 libatrip_a_CPPFLAGS = -I$(top_srcdir)/include/
-libatrip_a_SOURCES = ./atrip/Atrip.cxx
+libatrip_a_SOURCES = ./atrip/Atrip.cxx \
+                     ./atrip/Blas.cxx \
+                     ./atrip/Complex.cxx
+
+
+if WITH_CUDA
+libatrip_a_CPPFLAGS += $(CUDA_CXXFLAGS)
+libatrip_a_DEPENDENCIES = ./atrip/Equations.o
+libatrip_a_LIBADD = ./atrip/Equations.o
+./atrip/Equations.o: ./atrip/Equations.cxx
+	$(NVCC) -c -I../ $(CPPFLAGS) $(libatrip_a_CPPFLAGS) $< -o $@
+else
+libatrip_a_SOURCES += ./atrip/Equations.cxx
+endif
+
diff --git a/test/Makefile.am b/test/Makefile.am
index 833b84c..66acfae 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -15,3 +15,8 @@ main_LDADD += $(CTF_BUILD_PATH)/lib/libctf.a
 else
 main_LDADD += @LIBCTF_LD_LIBRARY_PATH@/libctf.a
 endif
+
+if WITH_CUDA
+main_CXXFLAGS = $(CUDA_CXXFLAGS)
+main_LDADD += $(CUDA_LDFLAGS)
+endif