diff --git a/build/temp.macosx-10.7-x86_64-3.7/pytdm_ripper.o b/build/temp.macosx-10.7-x86_64-3.7/pytdm_ripper.o
new file mode 100644
index 0000000..4a367fb
Binary files /dev/null and b/build/temp.macosx-10.7-x86_64-3.7/pytdm_ripper.o differ
diff --git a/lib/tdm_ripper.cpp b/lib/tdm_ripper.cpp
index 1a57e7a..58413c9 100644
--- a/lib/tdm_ripper.cpp
+++ b/lib/tdm_ripper.cpp
@@ -1,18 +1,18 @@
 
 #include "tdm_ripper.hpp"
 
-tdm_ripper::tdm_ripper():
-  tdmfile_(""), tdxfile_(""), filesprovided_(false),
-  num_channels_(0), num_groups_(0),
-  channel_id_(0), group_id_(0), channel_name_(0), group_name_(0),
-  num_channels_group_(0), channels_group_(0),
-  byteoffset_(0), length_(0), type_(0)
-{
-
-}
+// tdm_ripper::tdm_ripper():
+//   tdmfile_(""), tdxfile_(""), filesprovided_(false),
+//   num_channels_(0), num_groups_(0),
+//   channel_id_(0), group_id_(0), channel_name_(0), group_name_(0),
+//   num_channels_group_(0), channels_group_(0),
+//   byteoffset_(0), length_(0), type_(0)
+// {
+//
+// }
 
 tdm_ripper::tdm_ripper(std::string tdmfile, std::string tdxfile):
-  tdmfile_(tdmfile), tdxfile_(tdxfile), filesprovided_(true),
+  tdmfile_(tdmfile), tdxfile_(tdxfile), //filesprovided_(true),
   num_channels_(0), num_groups_(0),
   channel_id_(0), group_id_(0), channel_name_(0), group_name_(0),
   num_channels_group_(0), channels_group_(0),
@@ -20,18 +20,18 @@ tdm_ripper::tdm_ripper(std::string tdmfile, std::string tdxfile):
 {
   setup();
 }
-
-void tdm_ripper::setfiles(std::string tdmfile, std::string tdxfile)
-{
-  tdmfile_ = tdmfile;
-  tdxfile_ = tdxfile;
-  filesprovided_ = true;
-  setup();
-}
+//
+// void tdm_ripper::setfiles(std::string tdmfile, std::string tdxfile)
+// {
+//   tdmfile_ = tdmfile;
+//   tdxfile_ = tdxfile;
+//   filesprovided_ = true;
+//   setup();
+// }
 
 void tdm_ripper::setup()
 {
-  assert( filesprovided_ );
+  // assert( filesprovided_ );
 
   // TODO directly provide the C datatype to be used!!
   datatypes_ = {
@@ -146,7 +146,7 @@ void tdm_ripper::parse_structure()
 
   // check consistency of number of channelgroups
   int numgroups = count_occ_string(subtreedata.child("tdm_root").child_value("channelgroups"),"id");
-  assert( numgroups == num_groups_ );
+  if ( 0*numgroups == 0 ) assert( numgroups == num_groups_ );
 
   // check consistency of number of channels
   assert( num_channels_ == (int)channel_id_.size()
diff --git a/lib/tdm_ripper.hpp b/lib/tdm_ripper.hpp
index 61d2203..7bf139d 100644
--- a/lib/tdm_ripper.hpp
+++ b/lib/tdm_ripper.hpp
@@ -17,7 +17,7 @@ class tdm_ripper
   // .tdm and .tdx filenames
   std::string tdmfile_;
   std::string tdxfile_;
-  bool filesprovided_;
+  // bool filesprovided_;
 
   // endianness (true = little, false = big)
   bool endianness_, machine_endianness_;
@@ -45,10 +45,10 @@ class tdm_ripper
 
 public:
 
-  tdm_ripper();
+  // tdm_ripper();
   tdm_ripper(std::string tdmfile, std::string tdxfile = "");
 
-  void setfiles(std::string tdmfile, std::string tdxfile = "");
+  // void setfiles(std::string tdmfile, std::string tdxfile = "");
   void setup();
 
   void parse_structure();
diff --git a/main.o b/main.o
new file mode 100644
index 0000000..80e4793
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diff --git a/pytdm_ripper.pyx b/pytdm_ripper.pyx
index ee10edd..1aba3ce 100644
--- a/pytdm_ripper.pyx
+++ b/pytdm_ripper.pyx
@@ -1,18 +1,20 @@
-# cython: language_level=3
+# cython: language_level = 3
 # distutils: language = c++
-## distutils: sources = lib/tdm_ripper.cpp
 
-# from libcpp.string cimport string
-# from libcpp.vector cimport vector
+## distutils: sources = lib/tdm_ripper.cpp
 
 from tdm_ripper cimport tdm_ripper
 
 cdef class pytdmripper:
-    # C++ instance
-    cdef tdm_ripper cripp
+
+    # use pointer since there's no nullary constructor
+    cdef tdm_ripper*cripp
 
     def __cinit__(self, string tdmfile, string tdxfile):
-        self.cripp = tdm_ripper(tdmfile,tdxfile)
+        self.cripp = new tdm_ripper(tdmfile,tdxfile)
 
-    def setfiles(self, string tdmfile, string tdxfile):
-        self.cripp(tdmfile,tdxfile)
+    def __dealloc__(self):
+        del self.cripp
+
+    # def setfiles(self, string tdmfile, string tdxfile):
+    #     self.cripp(tdmfile,tdxfile)
diff --git a/setup.py b/setup.py
index 6127597..d583dbf 100644
--- a/setup.py
+++ b/setup.py
@@ -10,7 +10,7 @@ extensions = Extension(
     include_dirs=["lib"],
     language='c++',
     extra_compile_args=['-stdlib=libc++','-std=c++11'],
-    extra_link_args=['-std=c++11'],
+    extra_link_args=['-stdlib=libc++','-std=c++11'],
 )
 
 setup(
diff --git a/tdm_ripper.cpython-37m-darwin.so b/tdm_ripper.cpython-37m-darwin.so
new file mode 100755
index 0000000..05c25ed
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diff --git a/tdm_ripper.o b/tdm_ripper.o
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index 0000000..55072f2
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diff --git a/tdm_ripper.pxd b/tdm_ripper.pxd
index 973422a..1775814 100644
--- a/tdm_ripper.pxd
+++ b/tdm_ripper.pxd
@@ -1,14 +1,14 @@
-
+# use some C++ STL libraries
 from libcpp.string cimport string
 from libcpp.vector cimport vector
 
-# use only in absence of # distutils: sources = Rectangle.cpp in .pyx
+# use only in absence of # distutils: sources = lib/tdm_ripper.cpp in .pyx
 cdef extern from "tdm_ripper.cpp":
     pass
 
 cdef extern from "tdm_ripper.hpp":
     cdef cppclass tdm_ripper:
-        tdm_ripper() except +
+    #    tdm_ripper() except +
         tdm_ripper(string, string) except +
-        void setfiles(string, string)
-        void setup()
+        # void setfiles(string, string)
+        # void setup()