diff --git a/qpms/qpms_c.pyx b/qpms/qpms_c.pyx
index ea4d433..c2437ad 100644
--- a/qpms/qpms_c.pyx
+++ b/qpms/qpms_c.pyx
@@ -959,8 +959,8 @@ cdef class ScatteringSystem:
         cdef ccart3_t res
         cdef cart3_t pos
         cdef Py_ssize_t i
-        with nogil, parallel(), boundscheck(False), wraparound(False):
-            for i in prange(evalpos_a.shape[0]):
+        with nogil:
+            for i in range(evalpos_a.shape[0]):
                 pos.x = evalpos_a[i,0]
                 pos.y = evalpos_a[i,1]
                 pos.z = evalpos_a[i,2]
@@ -1000,6 +1000,7 @@ def empty_lattice_modes_xy(EpsMu epsmu, reciprocal_basis, wavevector, double max
     free(omegas_c)
     return omegas
 
+
 cdef class _ScatteringSystemAtOmegaK:
     '''
     Wrapper over the C qpms_scatsys_at_omega_k_t structure
@@ -1045,8 +1046,8 @@ cdef class _ScatteringSystemAtOmegaK:
         cdef ccart3_t res
         cdef cart3_t pos
         cdef Py_ssize_t i
-        with nogil, wraparound(False), parallel():
-            for i in prange(evalpos_a.shape[0]):
+        with nogil:
+            for i in range(evalpos_a.shape[0]):
                 pos.x = evalpos_a[i,0]
                 pos.y = evalpos_a[i,1]
                 pos.z = evalpos_a[i,2]
@@ -1089,9 +1090,9 @@ cdef class _ScatteringSystemAtOmegaK:
         cdef ccart3_t *res
         cdef cart3_t pos
         cdef Py_ssize_t i, j
-        with nogil, wraparound(False), parallel():
+        with nogil:
             res = <ccart3_t *> malloc(fecv_size*sizeof(ccart3_t))
-            for i in prange(evalpos_a.shape[0]):
+            for i in range(evalpos_a.shape[0]):
                 pos.x = evalpos_a[i,0]
                 pos.y = evalpos_a[i,1]
                 pos.z = evalpos_a[i,2]
@@ -1259,18 +1260,17 @@ cdef class _ScatteringSystemAtOmega:
         cdef ccart3_t res
         cdef cart3_t pos
         cdef Py_ssize_t i
-        with wraparound(False), nogil, parallel():
-            for i in prange(evalpos_a.shape[0]):
-                pos.x = evalpos_a[i,0]
-                pos.y = evalpos_a[i,1]
-                pos.z = evalpos_a[i,2]
-                if alt:
-                    res = qpms_scatsysw_scattered_E__alt(self.ssw, btyp_c, &scv_view[0], pos)
-                else:
-                    res = qpms_scatsysw_scattered_E(self.ssw, btyp_c, &scv_view[0], pos)
-                results[i,0] = res.x
-                results[i,1] = res.y
-                results[i,2] = res.z
+        for i in range(evalpos_a.shape[0]):
+            pos.x = evalpos_a[i,0]
+            pos.y = evalpos_a[i,1]
+            pos.z = evalpos_a[i,2]
+            if alt:
+                res = qpms_scatsysw_scattered_E__alt(self.ssw, btyp_c, &scv_view[0], pos)
+            else:
+                res = qpms_scatsysw_scattered_E(self.ssw, btyp_c, &scv_view[0], pos)
+            results[i,0] = res.x
+            results[i,1] = res.y
+            results[i,2] = res.z
         return results.reshape(evalpos.shape)
 
     @boundscheck(False)
@@ -1316,9 +1316,9 @@ cdef class _ScatteringSystemAtOmega:
         cdef ccart3_t *res
         cdef cart3_t pos
         cdef Py_ssize_t i, j
-        with nogil, wraparound(False), parallel():
+        with nogil:
             res = <ccart3_t *> malloc(basissize*sizeof(ccart3_t)) # thread-local
-            for i in prange(evalpos_a.shape[0]):
+            for i in range(evalpos_a.shape[0]):
                 pos.x = evalpos_a[i,0]
                 pos.y = evalpos_a[i,1]
                 pos.z = evalpos_a[i,2]
diff --git a/setup.py b/setup.py
index 3fb7b3b..5cc2fb3 100755
--- a/setup.py
+++ b/setup.py
@@ -150,7 +150,7 @@ qpms_c = Extension('qpms.qpms_c',
         sources = ['qpms/qpms_c.pyx',],
         libraries = common_libs,
         include_dirs=['amos', 'qpms', numpy_includes],
-        extra_link_args=['-fopenmp'],
+        extra_link_args=['-fopenmp'], # needed?
         extra_compile_args=['-fopenmp'],
         )