diff --git a/src/hb-aat-map.cc b/src/hb-aat-map.cc
new file mode 100644
index 0000000..f2736bf
--- /dev/null
+++ b/src/hb-aat-map.cc
@@ -0,0 +1,62 @@
+/*
+ * Copyright © 2009,2010  Red Hat, Inc.
+ * Copyright © 2010,2011,2013  Google, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Red Hat Author(s): Behdad Esfahbod
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#include "hb-aat-map.hh"
+
+#include "hb-aat-layout.hh"
+
+
+void hb_aat_map_builder_t::add_feature (hb_tag_t tag,
+					unsigned int value)
+{
+  const hb_aat_feature_mapping_t *mapping = hb_aat_layout_find_feature_mapping (tag);
+  if (!mapping) return;
+
+  feature_info_t *info = features.push();
+  info->type = mapping->aatFeatureType;
+  info->setting = value ? mapping->selectorToEnable : mapping->selectorToDisable;
+}
+
+void
+hb_aat_map_builder_t::compile (hb_aat_map_t  &m,
+			       const int    *coords HB_UNUSED,
+			       unsigned int  num_coords HB_UNUSED)
+{
+  /* Sort features and merge duplicates */
+  if (features.len)
+  {
+    features.qsort ();
+    unsigned int j = 0;
+    for (unsigned int i = 1; i < features.len; i++)
+      if (features[i].type != features[j].type)
+	features[++j] = features[i];
+    features.shrink (j + 1);
+  }
+
+  hb_aat_layout_compile_map (this, &m);
+}
diff --git a/src/hb-aat-map.hh b/src/hb-aat-map.hh
new file mode 100644
index 0000000..846cdc1
--- /dev/null
+++ b/src/hb-aat-map.hh
@@ -0,0 +1,106 @@
+/*
+ * Copyright © 2018  Google, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#ifndef HB_AAT_MAP_HH
+#define HB_AAT_MAP_HH
+
+#include "hb.hh"
+
+
+struct hb_ot_shape_plan_t;
+
+struct hb_aat_map_t
+{
+  friend struct hb_aat_map_builder_t;
+
+  public:
+
+  inline void init (void)
+  {
+    memset (this, 0, sizeof (*this));
+    chain_flags.init ();
+  }
+  inline void fini (void)
+  {
+    chain_flags.fini ();
+  }
+
+  public:
+  hb_vector_t<hb_mask_t, 1> chain_flags;
+};
+
+struct hb_aat_map_builder_t
+{
+  public:
+
+  HB_INTERNAL hb_aat_map_builder_t (hb_face_t *face_,
+				    const hb_segment_properties_t *props_ HB_UNUSED) :
+				      face (face_)
+  {
+    features.init ();
+  }
+
+  ~hb_aat_map_builder_t (void)
+  {
+    features.fini ();
+  }
+
+  HB_INTERNAL void add_feature (hb_tag_t tag, unsigned int value=1);
+
+  HB_INTERNAL void compile (hb_aat_map_t  &m,
+			    const int    *coords,
+			    unsigned int  num_coords);
+
+  public:
+  struct feature_info_t
+  {
+    uint16_t  type;
+    uint16_t  setting;
+    unsigned  seq; /* For stable sorting only. */
+
+    static int cmp (const void *pa, const void *pb)
+    {
+      const feature_info_t *a = (const feature_info_t *) pa;
+      const feature_info_t *b = (const feature_info_t *) pb;
+      return (a->type != b->type) ? (a->type < b->type ? -1 : 1) :
+	     (a->seq < b->seq ? -1 : a->seq > b->seq ? 1 : 0);
+    }
+
+    int cmp (const short unsigned int *ty) const
+    {
+      return (type != *ty) ? (type < *ty ? -1 : 1) : 0;
+    }
+  };
+
+  public:
+  hb_face_t *face;
+
+  public:
+  hb_vector_t<feature_info_t, 32> features;
+};
+
+
+#endif /* HB_AAT_MAP_HH */
diff --git a/src/hb-ot-map.cc b/src/hb-ot-map.cc
index 82e989e..fd81099 100644
--- a/src/hb-ot-map.cc
+++ b/src/hb-ot-map.cc
@@ -175,6 +175,7 @@
   }
 
   /* Sort features and merge duplicates */
+  if (feature_infos.len)
   {
     feature_infos.qsort ();
     unsigned int j = 0;
diff --git a/src/hb-ot-shape.cc b/src/hb-ot-shape.cc
index 23da56c..065b4d4 100644
--- a/src/hb-ot-shape.cc
+++ b/src/hb-ot-shape.cc
@@ -71,7 +71,8 @@
   plan.props = props;
   plan.shaper = shaper;
   map.compile (plan.map, coords, num_coords);
-  aat_map.compile (plan.aat_map, coords, num_coords);
+  if (apply_morx)
+    aat_map.compile (plan.aat_map, coords, num_coords);
 
   plan.frac_mask = plan.map.get_1_mask (HB_TAG ('f','r','a','c'));
   plan.numr_mask = plan.map.get_1_mask (HB_TAG ('n','u','m','r'));
@@ -162,7 +163,6 @@
 			      unsigned int                    num_user_features)
 {
   hb_ot_map_builder_t *map = &planner->map;
-  hb_aat_map_builder_t *aat_map = &planner->aat_map;
 
   map->enable_feature (HB_TAG('r','v','r','n'));
   map->add_gsub_pause (nullptr);
@@ -228,7 +228,16 @@
 		      (feature->start == HB_FEATURE_GLOBAL_START &&
 		       feature->end == HB_FEATURE_GLOBAL_END) ?  F_GLOBAL : F_NONE,
 		      feature->value);
-    aat_map->add_feature (feature->tag, feature->value);
+  }
+
+  if (planner->apply_morx)
+  {
+    hb_aat_map_builder_t *aat_map = &planner->aat_map;
+    for (unsigned int i = 0; i < num_user_features; i++)
+    {
+      const hb_feature_t *feature = &user_features[i];
+      aat_map->add_feature (feature->tag, feature->value);
+    }
   }
 }