diff --git a/Makefile b/Makefile
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+++ b/Makefile
@@ -0,0 +1,159 @@
+######################################################################
+#                            GNU MAKEFILE                            #
+######################################################################
+# There may be some trickery involved in this file; most of which is #
+# hopefully explained sufficiently.  This makefile is unlikely to    #
+# work with non-GNU make utilities.                                  #
+#                                                                    #
+######################################################################
+SHELL = /bin/bash
+# clear out suffix list
+.SUFFIXES :
+# declare suffixes allowed to be subject to implicit rules.
+.SUFFIXES : .f .o .f90
+
+current_version=4.0c
+tarname=NH3-Plus
+
+
+src = ./src/
+build = ./obj/
+bin = ./bin/
+
+ldir = $(src)lib/
+pdir = $(src)parser/
+mdl = $(src)model/
+
+
+# DEFINE THE PATH 
+
+VPATH = $(src)
+VPATH += $(ldir)
+VPATH += $(pdir)
+VPATH += $(mdl)
+
+
+# extra dir 
+extra_dirs = logs nnfits scans 
+gincl = -I$(src) -I$(pdir) -I$(ldir) -I$(mdl)
+
+# GFORTRAN COMPILER
+FC := gfortran 
+GFFLAGS = -O2 -fopenmp -fbackslash -fmax-errors=5 -Wall -Werror  
+GFFLAGS += -std=legacy -cpp -J$(build)
+GFFLAGS += $(gincl)
+#GFFLAGS +=  -Wall -Wextra -Werror -Wno-error=integer-division -Wno-error=conversion \
+           -Wno-error=intrinsic-shadow z
+GLLAPCK = -llapack
+
+DBGFFLAGS = -O0 -fcheck=bounds -fcheck=do -fcheck=mem -fcheck=pointer  -p -g -fsanitize=thread
+
+#cGINCL = -I -I$(pdir) -I$(ldir)
+
+GFFLAGS += $(GINCL)
+GFFLAGS += $(GLLAPCK)
+DBGFFLAGS += $(GLLAPCK)
+
+#IFORT COMPILER
+
+IFC := ifort 
+IFFLAGS = -O3 -qopenmp -qmkl -fpp -stand f95 -warn all -warn noerrors \
+         -fp-model precise -traceback -assume byterecl
+IFFLAGS += -g -diag-disable=10448
+DBGIFC  = -O0 -g -check all -traceback -fpp -warn all -fp-stack-check
+
+LDFLAGS = -llapack
+
+# CHOSE THE COMPILER
+###########################
+COMPILER = $(FC)
+
+ifeq ($(COMPILER),IFC)
+  FC = $(IFC)
+  FFLAGS = $(IFFLAGS)
+  DBGFLAGS = $(DBGIFC)
+else
+  #FC = $(FC)
+  FFLAGS = $(GFFLAGS)
+  DBGFLAGS = $(DBGFFLAGS)
+endif
+######################################################################
+### Functions
+######################################################################
+
+# return 'true' if file $(1) exists, else return ''
+file_exists = $(shell if [ -f $(1) ]; then echo "true"; fi)
+# return 'true' if file $(1) doesn't exist, else return ''
+file_lost = $(shell if [ ! -f $(1) ]; then echo "true"; fi)
+
+######################################################################
+### Objects
+######################################################################
+
+# Objects solely relying on ANN parameters
+ann_objects = backprop.o ff_neunet.o neuron_types.o \
+              axel.o nnmqo.o scans.o nnread.o
+parameter_object = accuracy_constants.o nn_params.o io_parameters.o \
+                 nn_common_param.o nndbg.o
+data_obj = Phase_correction.o data_transform.o write_error.o
+# Objects relying on both genetic & ANN params
+genann_objects = geNNetic.o iNNterface.o puNNch.o \
+                 mkNN.o error.o long_io.o parse_errors.o parser.o
+
+# Objects depending on model
+pln_objects = invariants_nh3.o nncoords_nh3.o fit_genetic.o pes_model.o \
+              dipole_model.o nnadia_nh3.o
+
+
+# Objects belonging to internal library
+lib_objects = misc.o ran_gv.o choldc.o diag.o \
+              qsort.o dmatrix.o imatrix.o strings.o ran.o \
+              fileread.o keyread.o long_keyread.o
+
+# Objects from hell; if it exists, don't compile it
+hell_objects = $(ldir)random.o
+hell_flags = -O3 -fopenmp -std=legacy
+
+project_objects = $(ann_objects) $(data_obj) $(genann_objects) $(pln_objects)
+objects = $(addprefix $(build),$(parameter_object) $(project_objects) $(lib_objects))
+
+main = genANN
+
+######################################################################
+### Remaining include files
+######################################################################
+
+gen_include = keylist.incl errcat.incl
+
+# Misc. files generated during compilation
+trash = *__genmod* *~ *\# *.g .mod
+
+$(main) : $(objects)
+ifeq ($(call file_exists,$(hell_objects)),)
+	$(MAKE) hell 
+endif 
+	$(FC) $(FFLAGS) $(hell_objects) $(objects) $(LDFLAGS) -o $(bin)$(main) 
+
+$(build)%.o : %.f 
+	$(FC) -c $(FFLAGS) $< -o $@
+$(build)%.o : %.f90
+	$(FC) -c $(FFLAGS) $< -o $@
+
+$(hell_objects) : $(ldir)random.f
+	$(FC) -c $(hell_flags) $< -o $@
+
+# making 
+
+.PHONY : clean dirs neat hell pyram_ANN all debug  
+clean: 
+	rm -rf $(build)*.o $(build)*.mod $(hell_objects) $(trash) $(bin)$(main)
+#	$(RM) $(objects) $(hell_objects) $(trash) $(bin)/$(main)
+dirs:
+	@mkdir -p $(build) $(bin) $(extra_dirs)
+neat:
+	$(RM) -f $(TRASH)
+hell : $(hell_objects)
+
+debug: override FFLAGS += $(DBGFLAGS) 
+debug: clean $(hell) $(main)
+all : clean  hell $(main) pyram_ANN libdipole_surface.a