diff --git a/.gitignore b/.gitignore
index dfec331..74334c5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,8 @@
 *.o
 *.a
+*.so
 *~
 *.ptx
 *.ptxh
+*.cle
+*.clh
diff --git a/gpl-3.0.txt b/LICENSE
similarity index 100%
rename from gpl-3.0.txt
rename to LICENSE
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..fd28e3b
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,213 @@
+CXX ?= g++
+CC ?= gcc
+PREFIX ?= /usr/local
+
+
+.PHONY: all
+all: libsapporo.a libsapporo.so emulated_interfaces
+
+
+# Detect CUDA
+ifndef CUDA_TK
+    NVCC := $(shell which nvcc || echo NOTFOUND)
+    ifeq ($(NVCC), NOTFOUND)
+        $(info The nvcc command is not available in your shell.)
+        $(info To compile with CUDA, please install it, set up your environment)
+        $(info according to the CUDA installation instructions, and try again.)
+        $(info )
+    else
+        CUDA_TK := $(dir $(NVCC))..
+        CUDA_AVAILABLE := 1
+    endif
+else
+    NVCC ?= $(CUDA_TK)/bin/nvcc
+    CUDA_AVAILABLE := 1
+endif
+
+
+# Detect OpenCL
+OPENCL_LDFLAGS := -lOpenCL
+ifdef OPENCL
+    OPENCL_LDFLAGS := -L$(OPENCL)/lib -lOpenCL
+endif
+
+OPENCL_STATUS := $(shell echo 'int main() {}' | $(CXX) -x c++ $(OPENCL_LDFLAGS) - && rm a.out || echo NOTFOUND)
+
+ifeq ($(OPENCL_STATUS), NOTFOUND)
+    $(info OpenCL support was not detected on the system.)
+    $(info If it is installed in a non-standard location, then set OPENCL to)
+    $(info the installation prefix and try again.)
+    $(info )
+else
+    OPENCL_AVAILABLE := 1
+endif
+
+
+# Select backend
+ifeq ($(filter clean,$(MAKECMDGOALS)),)
+ifndef BACKEND
+    ifdef CUDA_AVAILABLE
+        $(info BACKEND not set and CUDA was detected, using CUDA)
+        BACKEND := CUDA
+    else
+        ifdef OPENCL_AVAILABLE
+            $(info BACKEND not set and OpenCL was detected, using OpenCL)
+            BACKEND := OpenCL
+        else
+            $(error BACKEND not set and neither CUDA nor OpenGL was detected.)
+        endif
+    endif
+else
+    ifeq ($(BACKEND), CUDA)
+        ifndef CUDA_AVAILABLE
+            $(error BACKEND set to CUDA but it was not found.)
+        endif
+        $(info Using selected backend CUDA)
+    else
+        ifeq ($(BACKEND), OpenCL)
+            ifndef OPENCL_AVAILABLE
+                $(error BACKEND set to OpenCL but it was not found.)
+            endif
+        else
+            $(error BACKEND set to unknown value "$(BACKEND)", please use CUDA or OpenCL)
+        endif
+        $(info Using selected backend OpenCL)
+    endif
+endif
+endif
+$(info )
+
+# Testing/optimisation support
+ifdef NTHREADS
+    CXXFLAGS += -DNTHREADS=$(NTHREADS) -DTIMING_STATS=1
+endif
+
+ifdef NBLOCKS_PER_MULTI
+    CXXFLAGS += -DNBLOCKS_PER_MULTI=$(NBLOCKS_PER_MULTI) -DTIMING_STATS=1
+endif
+
+
+# CUDA kernels
+ifeq ($(BACKEND), CUDA)
+
+INCLUDES = -I$(CUDA_TK)
+CXXFLAGS += -D__INCLUDE_KERNELS__
+LDFLAGS += -lcuda -fopenmp
+
+CUDA_SRC = $(wildcard src/CUDA/*.cu)
+PTX = $(CUDA_SRC:src/CUDA/%.cu=src/CUDA/%.ptx)
+PTXH = $(CUDA_SRC:src/CUDA/%.cu=src/CUDA/%.ptxh)
+NVCCFLAGS += -Isrc
+
+KERNELS = $(PTX) $(PTXH)
+
+%.ptx: %.cu
+	$(NVCC) --forward-unknown-to-host-compiler $(CXXFLAGS) $(NVCCFLAGS) -ptx $< -o $@
+
+src/CUDA/%.ptxh: src/CUDA/%.ptx
+	xxd -i $< $@
+
+endif
+
+
+# OpenCL kernels
+ifeq ($(BACKEND), OpenCL)
+
+ifdef OPENCL
+    CXXFLAGS += -I$(OPENCL)/include
+    LDFLAGS += -L$(OPENCL)/lib
+endif
+
+INCLUDES =
+CXXFLAGS += -D_OCL_ -D__INCLUDE_KERNELS__
+LDFLAGS += -lOpenCL -fopenmp
+
+OPENCL_SRC = $(wildcard src/OpenCL/*.cl)
+CLE = $(OPENCL_SRC:src/OpenCL/%.cl=src/OpenCL/%.cle)
+CLH = $(OPENCL_SRC:src/OpenCL/%.cl=src/OpenCL/%.clh)
+
+KERNELS = $(CLE) $(CLH)
+
+%.cle: %.cl
+	$(CC) -E -Isrc -o $@ - <$<
+
+# xxd names the variable after the file name argument, and we expect
+# the variable to not have a src_ prefix, so we have to remove it.
+src/OpenCL/%.clh: src/OpenCL/%.cle
+	cd src && xxd -i $(<:src/%=%) $(@:src/%=%)
+
+endif
+
+
+# Main implementation
+CXX_SRC := $(wildcard src/*.cpp src/SSE_AVX/*.cpp)
+OBJS := $(CXX_SRC:%.cpp=%.o)
+INCLUDES += -Isrc
+CXXFLAGS += $(INCLUDES) -fPIC -g -O3 -Wall -Wextra -Wstrict-aliasing=2 -fopenmp
+
+src/sapporohostclass.o: $(KERNELS)
+
+%.o: %.cpp
+	$(CXX) $(CXXFLAGS) -c $< -o $@
+
+libsapporo.a: $(OBJS)
+	ar qv $@ $^
+
+libsapporo.so: $(OBJS)
+	$(CXX) -o $@ -shared $^ $(LDFLAGS)
+
+
+# API compatibility libraries
+EMU_SRC := $(wildcard src/interfaces/*lib.cpp)
+EMU_STATIC_LIBS := $(EMU_SRC:src/interfaces/%lib.cpp=lib%.a)
+EMU_SHARED_LIBS := $(EMU_SRC:src/interfaces/%lib.cpp=lib%.so)
+
+.PHONY: emulated_interfaces
+emulated_interfaces: $(EMU_STATIC_LIBS) $(EMU_SHARED_LIBS)
+
+$(EMU_STATIC_LIBS): libsapporo.a
+
+$(EMU_SHARED_LIBS): libsapporo.so
+
+
+lib%.a: src/interfaces/%lib.o
+	ar qv $@ $^
+
+lib%.so: src/interfaces/%lib.o
+	$(CXX) -o $@ -shared $^ -L. -lsapporo $(LDFLAGS)
+
+
+# Installation
+INSTALLED_LIBS := $(PREFIX)/lib/libsapporo.a $(PREFIX)/lib/libsapporo.so
+INSTALLED_LIBS += $(EMU_STATIC_LIBS:%.a=$(PREFIX)/lib/%.a)
+INSTALLED_LIBS += $(EMU_SHARED_LIBS:%.so=$(PREFIX)/lib/%.so)
+
+INSTALLED_LIBS: $(PREFIX)/lib
+
+HEADERS := $(wildcard include/*)
+INSTALLED_HEADERS := $(HEADERS:include/%=$(PREFIX)/include/%)
+
+INSTALLED_HEADERS: $(PREFIX)/include
+
+$(PREFIX)/include:
+	mkdir -p $(PREFIX)/include
+
+$(PREFIX)/include/%: include/% $(PREFIX)/include
+	install -m 644 $< $@
+
+$(PREFIX)/lib:
+	mkdir -p $(PREFIX)/lib
+
+$(PREFIX)/lib/%: % $(PREFIX)/lib
+	install -m 644 $< $@
+
+.PHONY: install
+install: $(INSTALLED_LIBS) $(INSTALLED_HEADERS)
+
+
+# Clean-up
+.PHONY: clean
+clean:
+	rm -f *.a *.so src/*.o src/SSE_AVX/SSE/*.o src/SSE_AVX/AVX/*.o
+	rm -f src/CUDA/*.ptx src/CUDA/*.ptxh src/OpenCL/*.cle src/OpenCL/*.clh
+
diff --git a/README.extended b/README.extended
index c604e72..d81cb59 100644
--- a/README.extended
+++ b/README.extended
@@ -86,15 +86,33 @@ With some luck a simple 'make' in the lib folder is sufficient to
 build the library, if not then here are some pointers:
 
 CUDA
-To build the CUDA library; Set the 'CUDA_TK' path to the location
-where the CUDA toolkit is installed e.g.. CUDA_TK = /usr/local/cuda and
-type: 'make' .
+
+If CUDA is installed via the nVidia installer, Conda, or HPC modules,
+then it should be detected automatically by the build system. If it
+somehow isn't, then you can try to set 'CUDA_TK' to the location where
+it is installed, e.g.
+
+CUDA_TK=/usr/local/cuda make
+
 
 OpenCL
-To build the CUDA library; Set the 'CUDA_TK' path to the location
-where the cuda or AMD OpenCL toolkit is installed eg. CUDA_TK =
-/usr/local/cuda or CUDA_TK = /opt/AMDAPP/ and type: 'make -f
-Makefile_ocl' .
+
+If OpenCL is installed in a standard location (e.g. via apt or yum),
+then it should be detected automatically by the build system. If it
+isn't, then you can set the 'OPENCL' variable to the location where
+it is installed, e.g.
+
+OPENCL=/opt/opencl make
+
+If both CUDA and OpenCL are detected, then CUDA is used by default.
+To select OpenCL, set BACKEND to OpenCL:
+
+BACKEND=OpenCL make
+
+You can combine these options as well:
+
+BACKEND=OpenCL OPENCL=/home/user/.local make
+
 
 Interfaces:
 The library has built-in support for a couple of default interfaces to
diff --git a/conda/conda_build_config.yaml b/conda/conda_build_config.yaml
new file mode 100644
index 0000000..99df767
--- /dev/null
+++ b/conda/conda_build_config.yaml
@@ -0,0 +1,4 @@
+gpu_backend:
+  - cuda
+  - opencl
+
diff --git a/conda/meta.yaml b/conda/meta.yaml
new file mode 100644
index 0000000..aa16b56
--- /dev/null
+++ b/conda/meta.yaml
@@ -0,0 +1,52 @@
+{% set name = "sapporo2" %}
+{% set version = "0.0.1" %}
+
+package:
+  name: {{ name|lower }}
+  version: {{ version }}
+
+source:
+  path: ../
+  # git_rev: work
+  # git_url: https://github.com/LourensVeen/sapporo2.git
+
+build:
+  number: 0
+  string: {{ gpu_backend }}_{{ PKG_BUILDNUM }}
+
+  script_env:
+    - BACKEND=CUDA                # [gpu_backend == 'cuda']
+    - BACKEND=OpenCL              # [gpu_backend == 'opencl']
+  script: make install
+
+  missing_dso_whitelist:
+    - "*/libcuda.so*"
+
+requirements:
+  build:
+    - {{ compiler('cxx') }}
+    - git
+    - git-lfs
+    - make
+    - cuda-compiler               # [linux and gpu_backend == 'cuda']
+    - pocl                        # [linux and gpu_backend == 'opencl']
+    - vim
+    # - conda-verify
+
+  host:
+    - ocl-icd                     # [linux and gpu_backend == 'opencl']
+
+  run:
+    - cuda-runtime                # [linux and gpu_backend == 'cuda']
+    - libgcc-ng
+    - libstdcxx-ng
+    - _openmp_mutex
+
+test:
+
+about:
+  home: https://github.com/treecode/sapporo2
+  summary: Library for emulating GRAPE6 n-body calculations
+  license: GPL-3.0-only
+  license_family: GPL
+  license_file: LICENSE
diff --git a/include/sapporo6thlib.h b/include/sapporo6thlib.h
new file mode 100644
index 0000000..87e245d
--- /dev/null
+++ b/include/sapporo6thlib.h
@@ -0,0 +1,79 @@
+/* 6th order integrator as implemented by Sapporo2
+*/
+
+void initialize_special(int ndev, int *list);
+
+void initialize();
+
+/*
+
+add = address
+pos, vel, acc, jrk, snp, crk,
+mass,
+time = current particle time
+id = unique particle id
+eps2 = softening of j-particle
+
+*/
+void set_j_particle(int add, double pos[3], double vel[3], double acc[3],
+                    double jrk[3], double snp[3], double crk[3], double mass,
+                    double time, int id, double eps2);
+
+/*
+
+Set time of the prediction
+
+time = time to which particles are predicted
+nj = amount of particles that are predicted
+
+*/
+void predict_all(double time, int nj);
+
+/*
+
+Do not execute prediction, but only copy the particles
+into the predicted buffers.
+
+*/
+void no_predict_all(double time, int nj);
+
+/*
+
+Return the predicted values for a particle at an address
+
+addr = address of the particle
+
+id   = the particle id
+mass = the mass of the particle
+eps2 = the softening value of the particle
+pos = buffer to store predicted position
+vel = buffer to store predicted velocity
+acc = buffer to store predicted acceleration
+
+*/
+void pick_up_predictor_2(int addr, int &id, double &mass, double &eps2,
+                         double pos[3],  double vel[3],  double acc[3]);
+
+/*
+
+Calculate the gravity on the i-particles
+
+//Input
+ni = number of particles to be integrated
+nj = number of sources
+pos, vel, acc, mass, eps2
+
+//Output
+acc, jrk, snp, potential (phi)
+nnb = nearest neighbour ID
+nnb_r2 = distance to the nearest neighbour. (Squared distance + softening)
+nnb_r2 =   double r2 = EPS2 + dx*dx + dy*dy + dz*dz;
+
+*/
+
+void calc_force_on_predictors(int ni, int nj, int ids[], double pos[][3],
+                              double vel[][3],double acc[][3], double mass[],
+                              double eps2[], double accNew[][3], double jrkNew[][3],
+                              double snpNew[][3], double crkNew[][3], double phi[],
+                              int nnb[], double nnb_r2[]);
+
diff --git a/include/sapporoG6lib.h b/include/sapporoG6lib.h
new file mode 100644
index 0000000..804fe99
--- /dev/null
+++ b/include/sapporoG6lib.h
@@ -0,0 +1,187 @@
+/* GRAPE6 API as implemented by Sapporo2
+ *
+ * See https://www.cfca.nao.ac.jp/files/grape6user.pdf for the documentation.
+ *
+ * Note that some functions appear to be missing, e.g. g6_set_nip() and
+ * g6_set_i_particle_scales_from_real_value().
+*/
+
+// Fortran ABI
+int g6_open_(int *id);
+
+int g6_close_(int *id);
+
+int g6_npipes_();
+
+int g6_set_tunit_(double*);
+
+int g6_set_xunit_(double*);
+
+int g6_set_ti_(int *id, double *ti);
+
+int g6_set_j_particle_(int *cluster_id,
+                       int *address,
+                       int *index,
+                       double *tj, double *dtj,
+                       double *mass,
+                       double k18[3], double j6[3],
+                       double a2[3], double v[3], double x[3]);
+
+void g6calc_firsthalf_(int *cluster_id,
+                       int *nj, int *ni,
+                       int index[],
+                       double xi[][3], double vi[][3],
+                       double aold[][3], double j6old[][3],
+                       double phiold[3],
+                       double *eps2, double h2[]);
+
+int g6calc_lasthalf_(int *cluster_id,
+                     int *nj, int *ni,
+                     int index[],
+                     double xi[][3], double vi[][3],
+                     double *eps2, double h2[],
+                     double acc[][3], double jerk[][3], double pot[]);
+
+int g6calc_lasthalf2_(int *cluster_id,
+                      int *nj, int *ni,
+                      int index[],
+                      double xi[][3], double vi[][3],
+                      double *eps2, double h2[],
+                      double acc[][3], double jerk[][3], double pot[],
+                      int *inn);
+
+int g6_initialize_jp_buffer_(int* cluster_id, int* buf_size) { cluster_id = cluster_id; buf_size=buf_size; return 0;}
+int g6_flush_jp_buffer_(int* cluster_id) { cluster_id = cluster_id; return 0;}
+int g6_reset_(int* cluster_id) {cluster_id = cluster_id; return 0;}
+int g6_reset_fofpga_(int* cluster_id) {cluster_id = cluster_id; return 0;}
+
+int g6_read_neighbour_list_(int* cluster_id);
+
+int g6_get_neighbour_list_(int *cluster_id,
+                           int *ipipe,
+                           int *maxlength,
+                           int *n_neighbours,
+                           int neighbour_list[]);
+
+// This is not part of the GRAPE6 API, but is useful for debugging.
+void get_j_part_data(int addr, int nj,
+                     double *pos,
+                     double *vel,
+                     double *acc,
+                     double *jrk,
+                     double *ppos,
+                     double *pvel,
+                     double &mass,
+                     double &eps2,
+                     int    &id);
+
+
+// C ABI
+// These forward to the Fortran versions above, which are actually implemented by
+// Sapporo2.
+
+extern "C" {
+
+inline int g6_open(int id) {
+    g6_open_(&id);
+}
+
+inline int g6_close(int id) {
+    g6_close(&id);
+}
+
+inline int g6_npipes() {
+    return g6_npipes_();
+}
+
+inline int g6_set_tunit(double tu) {
+    return g6_set_tunit_(&tu);
+}
+
+inline int g6_set_xunit(double xu) {
+    return g6_set_xunit_(&xu);
+}
+
+inline int g6_set_ti(int id, double ti) {
+    return g6_set_ti_(&id, &ti);
+}
+
+inline int g6_set_j_particle(int cluster_id,
+                             int address,
+                             int index,
+                             double tj, double dtj,
+                             double mass,
+                             double k18[3], double j6[3],
+                             double a2[3], double v[3], double x[3])
+{
+    return g6_set_j_particle(
+            &cluster_id, &address, &index, &tj, &dtj, &mass, k18, j6, a2, v, x);
+}
+
+inline void g6calc_firsthalf(int cluster_id,
+                             int nj, int ni,
+                             int index[],
+                             double xi[][3], double vi[][3],
+                             double aold[][3], double j6old[][3],
+                             double phiold[3],
+                             double eps2, double h2[])
+{
+    g6calc_firsthalf(
+            &cluster_id, &nj, &ni, index, xi, vi, aold, j6old, piold, &eps2, h2);
+}
+
+inline int g6calc_lasthalf(int cluster_id,
+                           int nj, int ni,
+                           int index[],
+                           double xi[][3], double vi[][3],
+                           double eps2, double h2[],
+                           double acc[][3], double jerk[][3], double pot[])
+{
+   return g6calc_lasthalf_(
+           &cluster_id, &nj, &ni, index, xi, vi, &eps2, h2, acc, jerk, pot);
+}
+
+inline int g6calc_lasthalf2(int cluster_id,
+                            int nj, int ni,
+                            int index[],
+                            double xi[][3], double vi[][3],
+                            double eps2, double h2[],
+                            double acc[][3], double jerk[][3], double pot[],
+                            int *inn)
+{
+    return g6calc_lasthalf2_(
+            &cluster_id, &nj, &ni, index, xy, vi, &eps2, h2, acc, jerk, pot, inn);
+}
+
+inline int g6_initialize_jp_buffer(int cluster_id, int buf_size) {
+    return g6_initialize_jp_buffer_(&cluster_id, &buf_size);
+}
+
+inline int g6_flush_jp_buffer(int cluster_id) {
+    return g6_flush_jp_buffer_(&cluster_id);
+}
+
+inline int g6_reset(int cluster_id) {
+    return g6_reset_(&cluster_id);
+}
+
+inline int g6_reset_fofpga(int cluster_id) {
+    return g6_reset_fofpga_(&cluster_id);
+}
+
+inline int g6_read_neighbour_list(int cluster_id) {
+    return g6_read_neighbour_list_(&cluster_id);
+}
+
+inline int g6_get_neighbour_list(int cluster_id,
+                                 int ipipe,
+                                 int maxlength,
+                                 int n_neighbours,
+                                 int neighbour_list[])
+{
+    return g6_get_neighbour_list(
+            &cluster_id, &ipipe, &maxlength, &n_neighbours, neighbour_list);
+}
+
+}
+
diff --git a/lib/Makefile b/lib/Makefile
deleted file mode 100644
index f70fd40..0000000
--- a/lib/Makefile
+++ /dev/null
@@ -1,114 +0,0 @@
-CXX = g++
-CC  = gcc
-LD  = g++ 
-F90  = ifort
-
-.SUFFIXES: .o .cpp .ptx .cu
-
-CUDA_TK  ?= /usr/local/cuda
-
-
-testRunFlags1=
-testRunFlags2=
-testRunFlags3=
-
-#Check for the defines 
-
-ifdef NTHREADS
-	testRunFlags1="-D NTHREADS=$(NTHREADS)"
-	testRunFlags3="-D TIMING_STATS=1"
-endif
-
-ifdef NBLOCKS_PER_MULTI
-	testRunFlags2="-D NBLOCKS_PER_MULTI=$(NBLOCKS_PER_MULTI)"
-	testRunFlags3="-D TIMING_STATS=1"
-endif
-
-OFLAGS = -g -O3 -Wall -Wextra -Wstrict-aliasing=2 -fopenmp
-
-#Use below if compiling with CPU_SUPPORT (SSE)
-#CXXFLAGS += ${testRunFlags} -fPIC $(OFLAGS) -I$(CUDA_TK)/include -msse4
-CXXFLAGS += ${testRunFlags} -fPIC $(OFLAGS) -I$(CUDA_TK)/include
-
-testRunFlags= $(testRunFlags1) $(testRunFlags2) $(testRunFlags3)
-$(info $(testRunFlags))
-
-NVCC      = $(CUDA_TK)/bin/nvcc
-
-
-# Support older CUDA versions out of the box
-NVCCVERSION=$(shell "${NVCC}" --version | grep ^Cuda | sed 's/^.* //g')
-ifeq "${NVCCVERSION}" "V5.5.22"
-	NVCCFLAGS ?= -arch sm_20
-else
-	NVCCFLAGS ?= -arch sm_30
-endif
-
-#NVCCFLAGS = -arch sm_35
-#NVCCFLAGS ?= -arch sm_30
-#NVCCFLAGS = -arch sm_20
-NVCCFLAGS +=  ${testRunFlags}
-
-# Use with Mac OS X
-# NVCCFLAGS = -arch sm_12 -Xcompiler="-Duint=unsigned\ int"
-
-LDFLAGS = -lcuda -fopenmp 
-
-
-INCLUDEPATH = ./include
-CXXFLAGS  += -I$(INCLUDEPATH) -I./
-NVCCFLAGS += -I$(INCLUDEPATH) -I./
-
-INTERFACEPATH =./interfaces
-
-CUDAKERNELSPATH = ./CUDAKernels
-CUDAKERNELS = kernels.cu
-
-CUDAPTX = $(CUDAKERNELS:%.cu=$(CUDAKERNELSPATH)/%.ptx)
-
-SRCPATH = src
-SRC = sapporohostclass.cpp sapporoG6lib.cpp sapporoYeblib.cpp sapporoG5lib.cpp sapporo6thlib.cpp
-OBJ = $(SRC:%.cpp=%.o)
-
-LIBOBJ = sapporohostclass.o $(INTERFACEPATH)/sapporoG6lib.o $(INTERFACEPATH)/sapporoYeblib.o
-LIBOBJ += $(INTERFACEPATH)/sapporoG5lib.o
-TARGET = libsapporo.a
-
-
-all:	  $(OBJ) $(CUDAPTX) $(TARGET)
-kernels:  $(CUDAPTX)
-
-
-$(TARGET): $(LIBOBJ)
-	ar qv $@ $^        
-
-%.o: $(SRCPATH)/%.cpp
-	$(CXX) $(CXXFLAGS) -c $< -o $@
-
-$(CUDAKERNELSPATH)/%.ptx: $(CUDAKERNELSPATH)/%.cu
-	$(NVCC) $(NVCCFLAGS) -ptx $< -o $@
-
-$(INCLUDEPATH)/%.ptxh: $(CUDAKERNELSPATH)/%.ptx
-	xxd -i $< $@
-
-clean:
-	/bin/rm -rf *.o *.ptx *.a 
-	cd $(INTERFACEPATH); /bin/rm -rf *.o; cd ..
-	cd $(CUDAKERNELSPATH); /bin/rm -rf *.ptx; cd ..
-	rm -f *.ptxh $(INCLUDEPATH)/*.ptxh
-
-$(OBJ): $(INCLUDEPATH)/*.h
-
-
-sapporohostclass.o : $(INCLUDEPATH)/kernels.ptxh $(INCLUDEPATH)/sapporohostclass.h $(INCLUDEPATH)/sapdevclass.h $(INCLUDEPATH)/defines.h
-$(CUDAKERNELSPATH)/kernels.ptx : $(INCLUDEPATH)/defines.h
-
-libsapporo.a : sapporohostclass.o
-
-
-
-
-
-
-
-
diff --git a/lib/Makefile_ocl b/lib/Makefile_ocl
deleted file mode 100644
index 3e26eab..0000000
--- a/lib/Makefile_ocl
+++ /dev/null
@@ -1,105 +0,0 @@
-CXX = g++
-CC  = gcc
-LD  = g++ 
-F90  = ifort
-
-.SUFFIXES: .o .cpp .ptx .cu
-
-CUDA_TK  = /usr/local/cuda
-#CUDA_TK  = /opt/AMDAPP/
-
-
-testRunFlags1=
-testRunFlags2=
-testRunFlags3=
-
-#Check for the defines 
-
-ifdef NTHREADS
-        testRunFlags1="-D NTHREADS=$(NTHREADS)"
-        testRunFlags3="-D TIMING_STATS=1"
-endif
-
-ifdef NBLOCKS_PER_MULTI
-        testRunFlags2="-D NBLOCKS_PER_MULTI=$(NBLOCKS_PER_MULTI)"
-        testRunFlags3="-D TIMING_STATS=1"
-endif
-
-OFLAGS = -g -Wall -Wextra -Wstrict-aliasing=2 -fopenmp  -D_OCL_  -D__INCLUDE_KERNELS__
-
-CXXFLAGS = ${testRunFlags}  -fPIC $(OFLAGS) -I$(CUDA_TK)/include -msse4 
-
-testRunFlags= $(testRunFlags1) $(testRunFlags2) $(testRunFlags3)
-$(info $(testRunFlags))
-
-NVCC      = $(CUDA_TK)/bin/nvcc  
-NVCCFLAGS = -arch sm_20 ${testRunFlags}
-
-# Use with Mac OS X
-# NVCCFLAGS = -arch sm_12 -Xcompiler="-Duint=unsigned\ int"
-
-LDFLAGS = -lOpenCL -fopenmp 
-
-
-INCLUDEPATH = ./include
-CXXFLAGS  += -I$(INCLUDEPATH) -I./
-NVCCFLAGS += -I$(INCLUDEPATH) -I./
-
-INTERFACEPATH =./interfaces
-
-SRCPATH = src
-SRC = sapporohostclass.cpp sapporoG6lib.cpp sapporoYeblib.cpp sapporoG5lib.cpp sapporo6thlib.cpp
-OBJ = $(SRC:%.cpp=%_ocl.o)
-
-LIBOBJ = sapporohostclass_ocl.o $(INTERFACEPATH)/sapporoG6lib_ocl.o $(INTERFACEPATH)/sapporoYeblib_ocl.o $(INTERFACEPATH)/sapporoG5lib_ocl.o
-TARGET = libsapporo_ocl.a
-
-OCLKERNELSPATH = ./OpenCLKernels
-OCLKERNELS=kernels4th.cl  kernels4thDP.cl  kernels6th.cl  kernelsG5DS.cl  kernelsG5SP.cl  sharedKernels.cl
-OPENCL_CLH = $(OCLKERNELS:%.cl=$(INCLUDEPATH)/%.clh)
-
-all:	  $(OBJ) $(TARGET)
-	echo $(OPENCL_CLH)
-    
-$(TARGET): $(LIBOBJ)
-	ar qv $@ $^        
-
-%_ocl.o: $(SRCPATH)/%.cpp 
-	$(CXX) $(CXXFLAGS) -c $< -o $@
-
-$(INTERFACEPATH)/%_ocl.o: $(INTERFACEPATH)/%.cpp
-	$(CXX) $(CXXFLAGS) -c $< -o $@
-
-
-$(CUDAKERNELSPATH)/%.ptx: $(CUDAKERNELSPATH)/%.cu
-	$(NVCC) $(NVCCFLAGS) -ptx $< -o $@
-
-
-$(OCLKERNELSPATH)/%.cle: $(OCLKERNELSPATH)/%.cl
-	rm -f OpenCL
-	ln -s $(OCLKERNELSPATH) OpenCL
-	$(CC) -E -I.  -c - -o $@ < $<
-	rm OpenCL
-    
-$(INCLUDEPATH)/%.clh: $(OCLKERNELSPATH)/%.cle
-	xxd -i $< $@
-    
-clean:
-	/bin/rm -rf *.o *.ptx *.a 
-	cd $(INTERFACEPATH); /bin/rm -rf *.o; cd ..
-	cd $(CUDAKERNELSPATH); /bin/rm -rf *.ptx; cd ..
-	rm -f *.clh $(INCLUDEPATH)/*.clh
-
-$(OBJ): $(INCLUDEPATH)/*.h
-
-
-sapporohostclass_ocl.o : $(OPENCL_CLH) $(INCLUDEPATH)/sapporohostclass.h $(INCLUDEPATH)/sapdevclass.h $(INCLUDEPATH)/defines.h
-
-libsapporo_ocl.a : sapporohostclass_ocl.o
-
-
-
-
-
-
-
diff --git a/lib/CUDAKernels/kernels.cu b/src/CUDA/kernels.cu
similarity index 99%
rename from lib/CUDAKernels/kernels.cu
rename to src/CUDA/kernels.cu
index ebb271c..b0ca6ad 100644
--- a/lib/CUDAKernels/kernels.cu
+++ b/src/CUDA/kernels.cu
@@ -15,7 +15,7 @@ Sixt order hermite, in double precision, including neighbour lists
 
 #include <stdio.h>
 
-#include "include/defines.h"
+#include "defines.h"
 
 #define inout
 #define __out
@@ -206,7 +206,7 @@ __device__ __forceinline__  double RSQRT(double val) { return rsqrt(val); }
 // template<>           __device__ __forceinline__  double RSQRT(double val) { return 1.0/sqrt(val); }
 
 
-
+#if __CUDA_ARCH__ < 600
 __device__ double atomicAdd(double* address, double val)
 {
     unsigned long long int* address_as_ull =
@@ -220,6 +220,7 @@ __device__ double atomicAdd(double* address, double val)
     } while (assumed != old);
     return __longlong_as_double(old);
 }
+#endif
 
 
 __device__ __forceinline__ double atomicMin(double *address, double val)
diff --git a/lib/OpenCLKernels/kernels4th.cl b/src/OpenCL/kernels4th.cl
similarity index 100%
rename from lib/OpenCLKernels/kernels4th.cl
rename to src/OpenCL/kernels4th.cl
diff --git a/lib/OpenCLKernels/kernels4thDP.cl b/src/OpenCL/kernels4thDP.cl
similarity index 100%
rename from lib/OpenCLKernels/kernels4thDP.cl
rename to src/OpenCL/kernels4thDP.cl
diff --git a/lib/OpenCLKernels/kernels6th.cl b/src/OpenCL/kernels6th.cl
similarity index 100%
rename from lib/OpenCLKernels/kernels6th.cl
rename to src/OpenCL/kernels6th.cl
diff --git a/lib/OpenCLKernels/kernelsG5DS.cl b/src/OpenCL/kernelsG5DS.cl
similarity index 100%
rename from lib/OpenCLKernels/kernelsG5DS.cl
rename to src/OpenCL/kernelsG5DS.cl
diff --git a/lib/OpenCLKernels/kernelsG5SP.cl b/src/OpenCL/kernelsG5SP.cl
similarity index 100%
rename from lib/OpenCLKernels/kernelsG5SP.cl
rename to src/OpenCL/kernelsG5SP.cl
diff --git a/lib/OpenCLKernels/sharedKernels.cl b/src/OpenCL/sharedKernels.cl
similarity index 100%
rename from lib/OpenCLKernels/sharedKernels.cl
rename to src/OpenCL/sharedKernels.cl
diff --git a/lib/include/SSE_AVX/AVX/avx.h b/src/SSE_AVX/avx.h
similarity index 94%
rename from lib/include/SSE_AVX/AVX/avx.h
rename to src/SSE_AVX/avx.h
index 3e6570f..50352b6 100644
--- a/lib/include/SSE_AVX/AVX/avx.h
+++ b/src/SSE_AVX/avx.h
@@ -31,8 +31,8 @@ namespace SIMD
 namespace SIMD
 {
 
-#include "avx_fp32.h"
-#include "avx_fp64.h"
+#include "SSE_AVX/avx_fp32.h"
+#include "SSE_AVX/avx_fp64.h"
 
   template<int ch, class T>
     T broadcast(const T x) { return T::template broadcast<ch>(x); }
diff --git a/lib/include/SSE_AVX/AVX/avx_fp32.h b/src/SSE_AVX/avx_fp32.h
similarity index 100%
rename from lib/include/SSE_AVX/AVX/avx_fp32.h
rename to src/SSE_AVX/avx_fp32.h
diff --git a/lib/include/SSE_AVX/AVX/avx_fp64.h b/src/SSE_AVX/avx_fp64.h
similarity index 100%
rename from lib/include/SSE_AVX/AVX/avx_fp64.h
rename to src/SSE_AVX/avx_fp64.h
diff --git a/lib/include/SSE_AVX/SSE/sse.h b/src/SSE_AVX/sse.h
similarity index 94%
rename from lib/include/SSE_AVX/SSE/sse.h
rename to src/SSE_AVX/sse.h
index 2b276fc..0b4bcf4 100644
--- a/lib/include/SSE_AVX/SSE/sse.h
+++ b/src/SSE_AVX/sse.h
@@ -31,8 +31,8 @@ namespace SIMD
 namespace SIMD
 {
 
-#include "sse_fp32.h"
-#include "sse_fp64.h"
+#include "SSE_AVX/sse_fp32.h"
+#include "SSE_AVX/sse_fp64.h"
 
   template<int ch, class T>
     T broadcast(const T x) { return T::template broadcast<ch>(x); }
diff --git a/lib/include/SSE_AVX/SSE/sse_fp32.h b/src/SSE_AVX/sse_fp32.h
similarity index 100%
rename from lib/include/SSE_AVX/SSE/sse_fp32.h
rename to src/SSE_AVX/sse_fp32.h
diff --git a/lib/include/SSE_AVX/SSE/sse_fp64.h b/src/SSE_AVX/sse_fp64.h
similarity index 100%
rename from lib/include/SSE_AVX/SSE/sse_fp64.h
rename to src/SSE_AVX/sse_fp64.h
diff --git a/lib/include/cudadev.h b/src/cudadev.h
similarity index 99%
rename from lib/include/cudadev.h
rename to src/cudadev.h
index b2af740..042c13c 100644
--- a/lib/include/cudadev.h
+++ b/src/cudadev.h
@@ -710,12 +710,14 @@ namespace dev {
         //           jitOptionCount++;
         //         }
 
-        
+
+#if CUDA_VERSION < 6000
         if(computeMode < CU_TARGET_COMPUTE_20)
         {
           fprintf(stderr,"Sapporo2 requires at least a Fermi or newer NVIDIA architecture.\n");
           exit(-1);
         }
+#endif
 
         //Set the architecture
         //         {
diff --git a/lib/include/defines.h b/src/defines.h
similarity index 89%
rename from lib/include/defines.h
rename to src/defines.h
index 16e01f7..726c836 100644
--- a/lib/include/defines.h
+++ b/src/defines.h
@@ -55,8 +55,15 @@ inline const char* get_kernelName(const int integrator,
     case SIXTH:
       if(precision == DOUBLESINGLE)
       {
+#ifdef _OCL_
+          fprintf(stderr, "ERROR: Sixth order integrator with double single precision");
+          fprintf(stderr, "ERROR: is not implemented in OpenCL, only in CUDA. Please");
+          fprintf(stderr, "ERROR: file an issue on GitHub if you need this combination.");
+          exit(1);
+#else
           perThreadSM = sizeof(float4)*2 + sizeof(float4) + sizeof(float3);
-	  return "dev_evaluate_gravity_sixth_DS"; 
+#endif
+          return "dev_evaluate_gravity_sixth_DS"; 
       }
       else if(precision == DOUBLE){
 #ifdef _OCL_
@@ -72,7 +79,7 @@ inline const char* get_kernelName(const int integrator,
   
   //Here we come if all switch/case/if combo's failed
   fprintf(stderr,"ERROR: Unknown combination of integrator type ( %d ) and precision ( %d ) \n", integrator, precision);
-  fprintf(stderr,"ERROR: See 'include/defines.h' for the possible combinations \n");
+  fprintf(stderr,"ERROR: See 'defines.h' for the possible combinations \n");
   exit(0);
   return "";
 }
diff --git a/lib/include/hostFunc.h b/src/hostFunc.h
similarity index 100%
rename from lib/include/hostFunc.h
rename to src/hostFunc.h
diff --git a/lib/interfaces/sapporo6thlib.cpp b/src/interfaces/sapporo6thlib.cpp
similarity index 100%
rename from lib/interfaces/sapporo6thlib.cpp
rename to src/interfaces/sapporo6thlib.cpp
diff --git a/lib/interfaces/sapporoG5lib.cpp b/src/interfaces/sapporoG5lib.cpp
similarity index 100%
rename from lib/interfaces/sapporoG5lib.cpp
rename to src/interfaces/sapporoG5lib.cpp
diff --git a/lib/interfaces/sapporoG6lib.cpp b/src/interfaces/sapporoG6lib.cpp
similarity index 100%
rename from lib/interfaces/sapporoG6lib.cpp
rename to src/interfaces/sapporoG6lib.cpp
diff --git a/lib/interfaces/sapporoYeblib.cpp b/src/interfaces/sapporoYeblib.cpp
similarity index 100%
rename from lib/interfaces/sapporoYeblib.cpp
rename to src/interfaces/sapporoYeblib.cpp
diff --git a/lib/include/ocldev.h b/src/ocldev.h
similarity index 97%
rename from lib/include/ocldev.h
rename to src/ocldev.h
index 453e67b..68ea286 100644
--- a/lib/include/ocldev.h
+++ b/src/ocldev.h
@@ -22,18 +22,18 @@
 #endif
 
 #ifdef __INCLUDE_KERNELS__
-extern unsigned char OpenCLKernels_kernels4th_cle[];
-extern unsigned int OpenCLKernels_kernels4th_cle_len;
-extern unsigned char OpenCLKernels_kernels4thDP_cle[];
-extern unsigned int OpenCLKernels_kernels4thDP_cle_len;
-extern unsigned char OpenCLKernels_kernels6th_cle[];
-extern unsigned int OpenCLKernels_kernels6th_cle_len;
-extern unsigned char OpenCLKernels_kernelsG5DS_cle[];
-extern unsigned int OpenCLKernels_kernelsG5DS_cle_len;
-extern unsigned char OpenCLKernels_kernelsG5SP_cle[];
-extern unsigned int OpenCLKernels_kernelsG5SP_cle_len;
-extern unsigned char OpenCLKernels_sharedKernels_cle[];
-extern unsigned int OpenCLKernels_sharedKernels_cle_len;
+extern unsigned char OpenCL_kernels4th_cle[];
+extern unsigned int OpenCL_kernels4th_cle_len;
+extern unsigned char OpenCL_kernels4thDP_cle[];
+extern unsigned int OpenCL_kernels4thDP_cle_len;
+extern unsigned char OpenCL_kernels6th_cle[];
+extern unsigned int OpenCL_kernels6th_cle_len;
+extern unsigned char OpenCL_kernelsG5DS_cle[];
+extern unsigned int OpenCL_kernelsG5DS_cle_len;
+extern unsigned char OpenCL_kernelsG5SP_cle[];
+extern unsigned int OpenCL_kernelsG5SP_cle_len;
+extern unsigned char OpenCL_sharedKernels_cle[];
+extern unsigned int OpenCL_sharedKernels_cle_len;
 #endif
 
 namespace dev {
@@ -70,8 +70,8 @@ namespace dev {
         int data_len = 0;
         if(temp.rfind("kernels4th.cl") != string::npos)
         { 
-            data = (char *) OpenCLKernels_kernels4th_cle;
-            data_len = OpenCLKernels_kernels4th_cle_len;
+            data = (char *) OpenCL_kernels4th_cle;
+            data_len = OpenCL_kernels4th_cle_len;
             fprintf(stderr, "Found compiled in version of file: %s\n", cFilename);
         } else {
             fprintf(stderr, "Could not find kernel file: %s\n", cFilename);
@@ -574,8 +574,8 @@ namespace dev {
     void copy(const memory &src, const cl_bool OCL_BLOCKING = CL_TRUE) {
       assert(ContextFlag);
       if (n != src.n) {
-	ocl_free();
-	cmalloc(src.n, DeviceMemFlags);
+        ocl_free();
+        allocate(src.n, DeviceMemFlags);
       }
       oclSafeCall(clEnqueueCopyBuffer(CommandQueue,
                                       src.DeviceMem,
diff --git a/lib/include/ocldev.h-default b/src/ocldev.h-default
similarity index 100%
rename from lib/include/ocldev.h-default
rename to src/ocldev.h-default
diff --git a/lib/include/sapdevclass.h b/src/sapdevclass.h
similarity index 99%
rename from lib/include/sapdevclass.h
rename to src/sapdevclass.h
index 01b996d..c7c175b 100644
--- a/lib/include/sapdevclass.h
+++ b/src/sapdevclass.h
@@ -12,7 +12,7 @@ to allocate, load, start functions, etc.
 */
 
 #ifdef _OCL_
-  #include "include/ocldev.h"
+  #include "ocldev.h"
 
   typedef cl_float2 float2;
   typedef cl_float4 float4;
@@ -28,7 +28,7 @@ to allocate, load, start functions, etc.
   typedef cl_int4 int4;
 
 #else
-  #include "include/cudadev.h"
+  #include "cudadev.h"
 #endif
 
 #include <cassert>
@@ -37,7 +37,7 @@ to allocate, load, start functions, etc.
 
 #include <sys/time.h>
 
-#include "include/defines.h"
+#include "defines.h"
 
 namespace sapporo2 {
 
diff --git a/lib/src/sapporohostclass.cpp b/src/sapporohostclass.cpp
similarity index 99%
rename from lib/src/sapporohostclass.cpp
rename to src/sapporohostclass.cpp
index 6cac1d4..b610a13 100644
--- a/lib/src/sapporohostclass.cpp
+++ b/src/sapporohostclass.cpp
@@ -18,14 +18,14 @@ vel_j.w = eps2
 
 #ifdef __INCLUDE_KERNELS__
 #ifdef _OCL_
-#include "kernels4th.clh"
-#include "kernels4thDP.clh"
-#include "kernels6th.clh"
-#include "kernelsG5DS.clh"
-#include "kernelsG5SP.clh"
-#include "sharedKernels.clh"
+#include "OpenCL/kernels4th.clh"
+#include "OpenCL/kernels4thDP.clh"
+#include "OpenCL/kernels6th.clh"
+#include "OpenCL/kernelsG5DS.clh"
+#include "OpenCL/kernelsG5SP.clh"
+#include "OpenCL/sharedKernels.clh"
 #else
-#include "kernels.ptxh"
+#include "CUDA/kernels.ptxh"
 #endif
 #endif
 
diff --git a/lib/include/sapporohostclass.h b/src/sapporohostclass.h
similarity index 100%
rename from lib/include/sapporohostclass.h
rename to src/sapporohostclass.h
diff --git a/lib/include/vec.h b/src/vec.h
similarity index 100%
rename from lib/include/vec.h
rename to src/vec.h
diff --git a/tests/.Makefile.swp b/tests/.Makefile.swp
new file mode 100644
index 0000000..6f7c95f
Binary files /dev/null and b/tests/.Makefile.swp differ
diff --git a/tests/.gitignore b/tests/.gitignore
new file mode 100644
index 0000000..583b07d
--- /dev/null
+++ b/tests/.gitignore
@@ -0,0 +1,2 @@
+/test_*
+CUDA
diff --git a/testCodes/Makefile b/tests/Makefile
similarity index 53%
rename from testCodes/Makefile
rename to tests/Makefile
index 3d9324f..f453db9 100644
--- a/testCodes/Makefile
+++ b/tests/Makefile
@@ -1,24 +1,25 @@
-CXX = g++
-CC  = gcc
-LD  = g++ 
-F90  = ifort
+CXX ?= g++
+CC  ?= gcc
+LD  ?= g++ 
+F90  ?= ifort
 
 .SUFFIXES: .o .cpp .ptx .cu
 
-SAPPOROPATH=../lib/
+SAPPOROPATH=..
 SAPLIB2 = sapporo
 SAPLIB = lib$(SAPLIB2).a
+SAPLIBG6 = sapporoG6
 
 
-CUDA_TK  = /usr/local/cuda
+CUDA_TK  ?= /usr/local/cuda
 
-OFLAGS = -g  -O3 -Wall -fopenmp -Wextra -Wstrict-aliasing=2 -fopenmp
-CXXFLAGS =  -fPIC $(OFLAGS) -I$(CUDA_TK)/include 
+OFLAGS = -g  -O3 -Wall -Wextra -Wstrict-aliasing=2 -fopenmp
+CXXFLAGS +=  -fPIC -fopenmp $(OFLAGS) -I$(CUDA_TK)/include 
 
-LDFLAGS = -lcuda -fopenmp  -L$(CUDA_TK)/lib64
+LDFLAGS += -lcuda -L$(CUDA_TK)/lib64
 
 INCLUDEPATH = $(SAPPOROPATH)/include 
-CXXFLAGS  += -I$(INCLUDEPATH) -I./ -I $(SAPPOROPATH)
+CXXFLAGS  += -I$(INCLUDEPATH) -I./ -I $(SAPPOROPATH)/src
 
 
 SRCPATH = src
@@ -31,34 +32,34 @@ all: $(OBJ) $(PROG) kernels
 
 
 kernels:
-	ln -s $(SAPPOROPATH)/CUDAKernels/ CUDA/
+	rm -f CUDA && ln -s $(SAPPOROPATH)/CUDA CUDA
 
 #$(PROG): $(OBJ)
-#	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -lsapporo
+#	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -lsapporo
 
 test_gravity_block_cuda : test_gravity_block.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)
 
 test_gravity_block_g5_cuda: test_gravity_block_g5.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)
 
 test_gravity_block_6th_cuda : test_gravity_block_6th.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2)  $(LDFLAGS)   
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2)  $(LDFLAGS)   
 
 test_performance_rangeN_cuda : test_performance_rangeN.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)  
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)  
 
 test_performance_blockStep_cuda : test_performance_blockStep.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
 
 test_performance_rangeN_6th_cuda : test_performance_rangeN_6th.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
 
 test_performance_rangeN_g5_cuda : test_performance_rangeN_g5.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
 
 test_integrator_cuda : test_integrator.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIBG6) $(LDFLAGS) 
 
 
 %.o: $(SRCPATH)/%.cpp
@@ -66,15 +67,4 @@ test_integrator_cuda : test_integrator.o
 
 
 clean:
-	/bin/rm -rf *.o *.ptx *.a $(PROG)
-
-
-$(OBJ): $(SAPPOROPATH)/$(SAPLIB)
-
-
-
-
-
-
-
-
+	/bin/rm -rf *.o *.ptx *.a $(PROG) CUDA
diff --git a/testCodes/Makefile_ocl b/tests/Makefile_ocl
similarity index 53%
rename from testCodes/Makefile_ocl
rename to tests/Makefile_ocl
index 9a50894..11ea0c1 100644
--- a/testCodes/Makefile_ocl
+++ b/tests/Makefile_ocl
@@ -1,24 +1,22 @@
-CXX = g++
-CC  = gcc
-LD  = g++ 
-F90  = ifort
+CXX ?= g++
 
 .SUFFIXES: .o .cpp .ptx .cu
 
-SAPPOROPATH=../lib/
-SAPLIB2 = sapporo_ocl
+SAPPOROPATH=..
+SAPLIB2 = sapporo
 SAPLIB = lib$(SAPLIB2).a
+SAPLIBG6 = sapporoG6
 
-CUDA_TK  = /usr/local/cuda
+CUDA_TK  ?= /usr/local/cuda
 #CUDA_TK  = /opt/AMDAPP/
 
-OFLAGS = -g -O3 -Wall -Wextra -Wstrict-aliasing=2 -fopenmp 
-CXXFLAGS =  -fPIC $(OFLAGS) -D_OCL_
+OFLAGS = -g -O3 -Wall -Wextra -Wstrict-aliasing=2 -fopenmp
+CXXFLAGS +=  -fPIC -fopenmp $(OFLAGS) -D_OCL_
 
-LDFLAGS = -lOpenCL -fopenmp  
+LDFLAGS += -lOpenCL -fopenmp  
 
-INCLUDEPATH = $(SAPPOROPATH)/include 
-CXXFLAGS  += -I$(INCLUDEPATH) -I./ -I $(SAPPOROPATH) -I$(CUDA_TK)/include 
+INCLUDEPATH = $(SAPPOROPATH)/include
+CXXFLAGS  += -I$(INCLUDEPATH) -I./ -I $(SAPPOROPATH)/src -I$(CUDA_TK)/include
 
 
 SRCPATH = src
@@ -30,46 +28,35 @@ PROG = test_gravity_block_ocl test_gravity_block_6th_ocl test_performance_rangeN
 all: $(OBJ) $(PROG) kernels
 
 kernels:
-	ln -s $(SAPPOROPATH)/OpenCLKernels OpenCL
+	rm -f OpenCL && ln -s $(SAPPOROPATH)/OpenCL OpenCL
 
 test_gravity_block_ocl : test_gravity_block_ocl.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)
 
 test_gravity_block_g5_ocl: test_gravity_block_g5_ocl.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS)
 
 test_gravity_block_6th_ocl : test_gravity_block_6th_ocl.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2)  $(LDFLAGS)   
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2)  $(LDFLAGS)   
 
 test_performance_rangeN_ocl : test_performance_rangeN_ocl.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2)  $(LDFLAGS) 
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2)  $(LDFLAGS) 
 
 test_performance_blockStep_ocl : test_performance_blockStep_ocl.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2)  $(LDFLAGS)
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2)  $(LDFLAGS)
 
 test_performance_rangeN_6th_ocl : test_performance_rangeN_6th_ocl.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
 
 test_performance_rangeN_g5_ocl : test_performance_rangeN_g5_ocl.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
 
 test_integrator_ocl : test_integrator_ocl.o
-	$(LD) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) $(LDFLAGS) 
+	$(CXX) $(LDFLAGS) $^ -o $@ -L $(SAPPOROPATH) -l$(SAPLIB2) -l$(SAPLIBG6) $(LDFLAGS) 
 
 %_ocl.o: $(SRCPATH)/%.cpp
 	$(CXX) $(CXXFLAGS) -c $< -o $@
 
 
 clean:
-	/bin/rm -rf *.o *.ptx *.a $(PROG)
-
-
-$(OBJ): $(SAPPOROPATH)/$(SAPLIB)
-
-
-
-
-
-
-
-
+	/bin/rm -rf *.o *.ptx *.a $(PROG) OpenCL
diff --git a/testCodes/README b/tests/README
similarity index 87%
rename from testCodes/README
rename to tests/README
index 4e667a4..3d1fff0 100644
--- a/testCodes/README
+++ b/tests/README
@@ -1,7 +1,7 @@
 Sapporo2, test and example programs
 
 This folder contains a set of test and example programs that can
-be used with Sapporo2. 
+be used with Sapporo2.
 
 ===============================================================================
 
@@ -13,12 +13,18 @@ Makefile and Makefile_ocl (the CUDA_TK variable)
 To build the CUDA versions:
 'make'
 
-Tol build the OpenCL versions:
-'make -f Makefile_ocl' 
+To build the OpenCL versions:
+'make -f Makefile_ocl'
 
-In both cases make sure you build the matching sapporo library in the 'lib' folder.
+In both cases make sure you build the matching sapporo library in the 'lib' folder, and
+use
 
-Make sure that the GPU kernel sources and ptx files are in a subfolder 'CUDA' can be 
+'export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:../lib'
+
+to ensure the linker can find the sapporo2 libraries, or better, use the absolute path
+to the 'lib' directory.
+
+Make sure that the GPU kernel sources and ptx files are in a subfolder 'CUDA' can be
 symlinked from the lib folder. This is done by default in the Makefiles.
 
 ===============================================================================
@@ -38,12 +44,12 @@ USAGE / Examples
 
 How to start a 4th order test using different precision:
 CUDA, 4th order default
-./test_gravity_block_cuda  
+./test_gravity_block_cuda
 ./test_gravity_block_cuda 16364 -> number of particles is 16384 using CUDA
 ./test_gravity_block_ocl  16364 -> number of particles is 16384 using OpenCL
 
 ./test_gravity_block_cuda 16364 CUDA/kernels4thDP.ptx 1 1  ->
-  number of particles is 16384 using CUDA, using a full double precision kernel, with 
+  number of particles is 16384 using CUDA, using a full double precision kernel, with
   integration order 1 (=FOURTH order) with precision 1 (=DOUBLE precision)
 ./test_gravity_block_ocl 16364 OpenCL/kernels4thDP.cl 1 1  ->
   same as above but now using OpenCL.
diff --git a/testCodes/runScripts/compile_timingTest.sh b/tests/runScripts/compile_timingTest.sh
similarity index 100%
rename from testCodes/runScripts/compile_timingTest.sh
rename to tests/runScripts/compile_timingTest.sh
diff --git a/testCodes/runScripts/profiler.conf b/tests/runScripts/profiler.conf
similarity index 100%
rename from testCodes/runScripts/profiler.conf
rename to tests/runScripts/profiler.conf
diff --git a/testCodes/runScripts/run_activeParticleSizeTest.sh b/tests/runScripts/run_activeParticleSizeTest.sh
similarity index 100%
rename from testCodes/runScripts/run_activeParticleSizeTest.sh
rename to tests/runScripts/run_activeParticleSizeTest.sh
diff --git a/testCodes/runScripts/run_rangeN.sh b/tests/runScripts/run_rangeN.sh
similarity index 100%
rename from testCodes/runScripts/run_rangeN.sh
rename to tests/runScripts/run_rangeN.sh
diff --git a/testCodes/sapporo2.config b/tests/sapporo2.config
similarity index 100%
rename from testCodes/sapporo2.config
rename to tests/sapporo2.config
diff --git a/testCodes/sapporo2.config.README b/tests/sapporo2.config.README
similarity index 100%
rename from testCodes/sapporo2.config.README
rename to tests/sapporo2.config.README
diff --git a/testCodes/src/g6lib.h b/tests/src/g6lib.h
similarity index 100%
rename from testCodes/src/g6lib.h
rename to tests/src/g6lib.h
diff --git a/testCodes/src/test_gravity_block.cpp b/tests/src/test_gravity_block.cpp
similarity index 100%
rename from testCodes/src/test_gravity_block.cpp
rename to tests/src/test_gravity_block.cpp
diff --git a/testCodes/src/test_gravity_block_6th.cpp b/tests/src/test_gravity_block_6th.cpp
similarity index 100%
rename from testCodes/src/test_gravity_block_6th.cpp
rename to tests/src/test_gravity_block_6th.cpp
diff --git a/testCodes/src/test_gravity_block_g5.cpp b/tests/src/test_gravity_block_g5.cpp
similarity index 100%
rename from testCodes/src/test_gravity_block_g5.cpp
rename to tests/src/test_gravity_block_g5.cpp
diff --git a/testCodes/src/test_integrator.cpp b/tests/src/test_integrator.cpp
similarity index 100%
rename from testCodes/src/test_integrator.cpp
rename to tests/src/test_integrator.cpp
diff --git a/testCodes/src/test_performance_blockStep.cpp b/tests/src/test_performance_blockStep.cpp
similarity index 100%
rename from testCodes/src/test_performance_blockStep.cpp
rename to tests/src/test_performance_blockStep.cpp
diff --git a/testCodes/src/test_performance_rangeN.cpp b/tests/src/test_performance_rangeN.cpp
similarity index 100%
rename from testCodes/src/test_performance_rangeN.cpp
rename to tests/src/test_performance_rangeN.cpp
diff --git a/testCodes/src/test_performance_rangeN_6th.cpp b/tests/src/test_performance_rangeN_6th.cpp
similarity index 100%
rename from testCodes/src/test_performance_rangeN_6th.cpp
rename to tests/src/test_performance_rangeN_6th.cpp
diff --git a/testCodes/src/test_performance_rangeN_g5.cpp b/tests/src/test_performance_rangeN_g5.cpp
similarity index 100%
rename from testCodes/src/test_performance_rangeN_g5.cpp
rename to tests/src/test_performance_rangeN_g5.cpp