diff --git a/Makefile.am b/Makefile.am
index 19edb5a21b6d4839c562091138cf584024186165..1c6072ab59f9c6f6b0a90b55374f2614c0a62603 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -17,24 +17,35 @@ AM_CPPFLAGS = -I$(srcdir) -ggdb
 
 ## generated libraries and sources
 
-lib_LTLIBRARIES = libniflib.la
+# (uncomment the libniflib stuff to build a C++ library)
 
-libniflib_la_SOURCES = \
-niflib.cpp \
-nif_math.cpp \
-NIF_Blocks.cpp \
-NIF_IO.cpp
+#lib_LTLIBRARIES = libniflib.la
+
+#libniflib_la_SOURCES = \
+#niflib.cpp \
+#nif_math.cpp \
+#NIF_Blocks.cpp \
+#NIF_IO.cpp \
+#docsys_extract.cpp
 
-libniflib_la_LDFLAGS = -version-info 0:0:0 -shared -no-undefined
+#libniflib_la_LDFLAGS = -version-info 0:0:0 -shared -no-undefined
 
 BUILT_SOURCES = swig_wrap.cpp
 SWIG_SOURCES = pyniflib.i
 pkgpython_PYTHON = niflib.py
 pkgpyexec_LTLIBRARIES = _niflib.la
-_niflib_la_SOURCES = swig_wrap.cpp $(SWIG_SOURCES)
+_niflib_la_SOURCES = \
+niflib.cpp \
+nif_math.cpp \
+NIF_Blocks.cpp \
+NIF_IO.cpp \
+docsys_extract.cpp \
+swig_wrap.cpp \
+$(SWIG_SOURCES)
 _niflib_la_CPPFLAGS = $(SWIG_PYTHON_CPPFLAGS)
 _niflib_la_LDFLAGS = -module -shared -no-undefined
-_niflib_la_LIBADD = libniflib.la
 
 swig_wrap.cpp: $(SWIG_SOURCES)
 	$(SWIG) $(SWIG_PYTHON_OPT) -o $@ $<
+
+CLEANFILES = swig_wrap.cpp