diff --git a/Doxyfile b/Doxyfile
index e3b078396cf875f937a3807401b4cc4ca222a6d0..25c7522440fa099635cc4da62d96ab7032398c6a 100644
--- a/Doxyfile
+++ b/Doxyfile
@@ -38,7 +38,7 @@ PROJECT_NUMBER         = 1
 # If a relative path is entered, it will be relative to the location 
 # where doxygen was started. If left blank the current directory will be used.
 
-OUTPUT_DIRECTORY       = doc
+OUTPUT_DIRECTORY       = docs
 
 # If the CREATE_SUBDIRS tag is set to YES, then doxygen will create 
 # 4096 sub-directories (in 2 levels) under the output directory of each output 
diff --git a/Makefile b/Makefile
index ba8c334bc025a5393e2423d08f7bff176bd6d335..939dd05736ae8d95a863f66a4f7c50ddec3bc0f7 100644
--- a/Makefile
+++ b/Makefile
@@ -36,13 +36,13 @@
 CXX= g++
 CC = $(CXX)
 LD = $(CXX)
-DEBUG = -g
+#DEBUG = -g
 RANLIB = ranlib
-#OPTIM = -O2
+OPTIM = -O2
 
 INCLUDE = -I.
 
-CXXFLAGS += -fPIC -D_REENTRANT $(DEBUG) $(OPTIM) $(WARN) $(INCLUDE)
+CXXFLAGS += -std=c++11 -fPIC -D_REENTRANT $(DEBUG) $(OPTIM) $(WARN) $(INCLUDE)
 CFLAGS = $(CXXFLAGS)
 PROJECTHOME = .
 ##############################################
@@ -150,15 +150,17 @@ doc:
 	doxygen 2>doxy.log
 
 docclean:
-	rm -rf doc doxy.log
+	rm -rf docs doxy.log
 clean:
 	rm -f *.o core* *.gcov *.gcno *.gcda *.grind *grind.core.* *.valgrind dump* gmon.out doxygen_log.txt dump* *.csv
-	rm -f $(PROJECTHOME)/lib/*.a $(PROJECTHOME)/lib/*.so*
 	rm -f test_spline test_inverse test_periodicspline test_freespline test_multipoly test_magnets test_dipole test_quadrupole test_sextupole test_kicker test_solenoid spltest
 	rm -f *.csv
+	rm -f doxy.log
 
 distclean: clean docclean
 	rm -f *~  .kdbgrc.*
+	rm -f $(PROJECTHOME)/lib/*.a $(PROJECTHOME)/lib/*.so*
+	rm -rf lib
 
 install: lib
 	install -d $(DESTDIRLIB)
diff --git a/README.md b/README.md
index eda029306ba503a58f20c083bd7538622ee20e1a..28cc9360e6f808adcffe59f52240b87bc7acaff2 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,44 @@
+
 # interpolator
 
 C++ library for interpolation of funziontions of real variable y=f(x).
 
 Various splines and mutipolynomial methods are implemented.
+
+# requirements
+
+reasonably up-to-date GNU C++ compiler
+
+# build 
+
+make test : build the test programs
+
+make lib : build only the shared library
+
+make libstatic: build the static (archive) library
+
+make doc : build the doxyfile based documentation
+
+make all : build lib , libstatic and test
+
+make install : install the libraries and header files in the standrd elettra development environment
+
+# usage
+
+see docs/htlm/annotated.html
+
+
+## History
+
+
+2012-01-15 : project created on gitlab, derived from CVS release_01_01_01
+
+## Credits
+Claudio Scafuri 
+Elettra-Sincrotrone Trieste S.C.p.A. di interesse nazionale
+Strada Statale 14 - km 163,5 in AREA Science Park
+34149 Basovizza, Trieste ITALY
+
+## License
+
+GPL 3