diff --git a/NEWS b/NEWS
index ff4f6e29d..890c258d8 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,18 @@
+Overview of changes leading to 2.3.0
+Thursday, December 20, 2018
+====================================
+- Fix regression on big-endian architectures.  Ouch!
+- Misc bug and build fixes.
+- Fix subsetting of simple GSUB/GDEF.
+- Merge CFF / CFF2 support contributed by Adobe.  This mostly involves
+  the subsetter, but also get_glyph_extents on CFF fonts.
+
+New API in hb-aat.h:
++hb_aat_layout_has_substitution()
++hb_aat_layout_has_positioning()
++hb_aat_layout_has_tracking()
+
+
 Overview of changes leading to 2.2.0
 Thursday, November 29, 2018
 ====================================
diff --git a/configure.ac b/configure.ac
index 4d7348eff..03155372b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,6 @@
 AC_PREREQ([2.64])
 AC_INIT([HarfBuzz],
-        [2.2.0],
+        [2.3.0],
         [https://github.com/harfbuzz/harfbuzz/issues/new],
         [harfbuzz],
         [http://harfbuzz.org/])
diff --git a/src/Makefile.am b/src/Makefile.am
index 3618d03a2..5ed629217 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -384,14 +384,20 @@ dump_use_data_SOURCES = dump-use-data.cc hb-ot-shape-complex-use-table.cc
 dump_use_data_CPPFLAGS = $(HBCFLAGS)
 dump_use_data_LDADD = libharfbuzz.la $(HBLIBS)
 
-check_PROGRAMS += test-ot-tag test-unicode-ranges
-TESTS += test-ot-tag test-unicode-ranges
+COMPILED_TESTS = test-iter test-ot-tag test-unicode-ranges
+check_PROGRAMS += $(COMPILED_TESTS)
+TESTS += $(COMPILED_TESTS)
+
+test_iter_SOURCES = test-iter.cc hb-static.cc
+test_iter_CPPFLAGS = $(HBCFLAGS) -DMAIN
+test_iter_LDADD = libharfbuzz.la $(HBLIBS)
 
 test_ot_tag_SOURCES = hb-ot-tag.cc
 test_ot_tag_CPPFLAGS = $(HBCFLAGS) -DMAIN
 test_ot_tag_LDADD = libharfbuzz.la $(HBLIBS)
 
 test_unicode_ranges_SOURCES = test-unicode-ranges.cc
+test_unicode_ranges_CPPFLAGS = $(HBCFLAGS) -DMAIN
 test_unicode_ranges_LDADD = libharfbuzz.la $(HBLIBS)
 
 TESTS_ENVIRONMENT = \
diff --git a/src/Makefile.sources b/src/Makefile.sources
index 98b622889..0da4abe05 100644
--- a/src/Makefile.sources
+++ b/src/Makefile.sources
@@ -36,6 +36,7 @@ HB_BASE_sources = \
 	hb-face.hh \
 	hb-font.cc \
 	hb-font.hh \
+	hb-iter.hh \
 	hb-kern.hh \
 	hb-machinery.hh \
 	hb-map.cc \
diff --git a/src/hb-aat-layout.cc b/src/hb-aat-layout.cc
index 8a868a054..8de8205f5 100644
--- a/src/hb-aat-layout.cc
+++ b/src/hb-aat-layout.cc
@@ -209,7 +209,7 @@ hb_aat_layout_compile_map (const hb_aat_map_builder_t *mapper,
  * @face:
  *
  * Returns:
- * Since: REPLACEME
+ * Since: 2.3.0
  */
 hb_bool_t
 hb_aat_layout_has_substitution (hb_face_t *face)
@@ -270,7 +270,7 @@ hb_aat_layout_remove_deleted_glyphs (hb_buffer_t *buffer)
  * @face:
  *
  * Returns:
- * Since: REPLACEME
+ * Since: 2.3.0
  */
 hb_bool_t
 hb_aat_layout_has_positioning (hb_face_t *face)
@@ -300,7 +300,7 @@ hb_aat_layout_position (const hb_ot_shape_plan_t *plan,
  * @face:
  *
  * Returns:
- * Since: REPLACEME
+ * Since: 2.3.0
  */
 hb_bool_t
 hb_aat_layout_has_tracking (hb_face_t *face)
diff --git a/src/hb-array.hh b/src/hb-array.hh
index d4df16546..af4233bfa 100644
--- a/src/hb-array.hh
+++ b/src/hb-array.hh
@@ -36,7 +36,7 @@ struct hb_sorted_array_t;
 template <typename Type>
 struct hb_array_t
 {
-  typedef Type ItemType;
+  typedef Type item_t;
   enum { item_size = hb_static_size (Type) };
 
   /*
diff --git a/src/hb-iter.hh b/src/hb-iter.hh
new file mode 100644
index 000000000..a919d4e32
--- /dev/null
+++ b/src/hb-iter.hh
@@ -0,0 +1,105 @@
+/*
+ * 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_ITER_HH
+#define HB_ITER_HH
+
+#include "hb.hh"
+
+
+/* Unified iterator object.
+ *
+ * The goal of this template is to make the same iterator interface
+ * available to all types, and make it very easy and compact to use.
+ * hb_iter_tator objects are small, light-weight, objects that can be
+ * copied by value.  If the collection / object being iterated on
+ * is writable, then the iterator returns lvalues, otherwise it
+ * returns rvalues.
+ */
+
+/* Base class for all iterators. */
+template <typename Iter, typename Item = typename Iter::__item_type__>
+struct hb_iter_t
+{
+  typedef Iter iter_t;
+  typedef Item item_t;
+
+  /* https://en.wikipedia.org/wiki/Curiously_recurring_template_pattern */ 
+  const iter_t* thiz () const { return static_cast<const iter_t *> (this); }
+        iter_t* thiz ()       { return static_cast<      iter_t *> (this); }
+
+  /* Operators. */
+  operator iter_t () { return iter(); }
+  explicit_operator bool () const { return more (); }
+  item_t& operator * () { return item (); }
+  item_t& operator [] (unsigned i) { return item (i); }
+  iter_t& operator += (unsigned count) { forward (count); return *thiz(); }
+  iter_t& operator ++ () { next (); return *thiz(); }
+  iter_t& operator -= (unsigned count) { rewind (count); return *thiz(); }
+  iter_t& operator -- () { prev (); return *thiz(); }
+  iter_t operator + (unsigned count) { iter_t c (*thiz()); c += count; return c; }
+  iter_t operator ++ (int) { iter_t c (*thiz()); ++*thiz(); return c; }
+  iter_t operator - (unsigned count) { iter_t c (*thiz()); c -= count; return c; }
+  iter_t operator -- (int) { iter_t c (*thiz()); --*thiz(); return c; }
+
+  /* Methods. */
+  iter_t iter () const { return *thiz(); }
+  item_t& item () const { return thiz()->__item__ (); }
+  item_t& item_at (unsigned i) const { return thiz()->__item_at__ (i); }
+  bool more () const { return thiz()->__more__ (); }
+  void next () { thiz()->__next__ (); }
+  void forward (unsigned n) { thiz()->__forward__ (n); }
+  void prev () { thiz()->__prev__ (); }
+  void rewind (unsigned n) { thiz()->__rewind__ (n); }
+  unsigned len () const { return thiz()->__len__ (); }
+
+  /*
+   * Subclasses overrides:
+   */
+
+  /* Access: Implement __item__(), or __item_at__() if random-access. */
+  item_t& __item__ () const { return thiz()->item_at (0); }
+  item_t& __item_at__ (unsigned i) const { return *(thiz() + i); }
+
+  /* Termination: Implement __more__() or __end__(). */
+  bool __more__ () const { return item () != thiz()->__end__ (); }
+  const item_t& __end__ () const { return iter_t::__sentinel__; }
+
+  /* Advancing: Implement __next__(), or __forward__() if random-access. */
+  void __next__ () { thiz()->forward (1); }
+  void __forward__ (unsigned n) { while (n--) next (); }
+
+  /* Rewinding: Implement __prev__() or __rewind__() if bidirectional. */
+  void __prev__ () { thiz()->rewind (1); }
+  void __rewind__ (unsigned n) { while (n--) prev (); }
+
+  /* Population: Implement __len__() if known. */
+  unsigned __len__ () const
+  { iter_t c (*thiz()); unsigned l = 0; while (c) { c++; l++; }; return l; }
+};
+
+
+#endif /* HB_ITER_HH */
diff --git a/src/hb-machinery.hh b/src/hb-machinery.hh
index 1205b1fea..fdb7b0a0d 100644
--- a/src/hb-machinery.hh
+++ b/src/hb-machinery.hh
@@ -390,7 +390,7 @@ struct hb_sanitize_context_t :
   {
     if (this->may_edit (obj, hb_static_size (Type)))
     {
-      const_cast<Type *> (obj)->set (v);
+      hb_assign (* const_cast<Type *> (obj), v);
       return true;
     }
     return false;
@@ -599,6 +599,8 @@ struct hb_serialize_context_t
     memcpy (ret, &obj, size);
     return ret;
   }
+  template <typename Type>
+  hb_serialize_context_t &operator << (const Type &obj) { embed (obj); return *this; }
 
   template <typename Type>
   Type *extend_size (Type &obj, unsigned int size)
@@ -665,7 +667,6 @@ template <typename Type>
 struct BEInt<Type, 1>
 {
   public:
-  typedef Type type;
   void set (Type V)      { v = V; }
   operator Type () const { return v; }
   private: uint8_t v;
@@ -674,7 +675,6 @@ template <typename Type>
 struct BEInt<Type, 2>
 {
   public:
-  typedef Type type;
   void set (Type V)
   {
     v[0] = (V >>  8) & 0xFF;
@@ -703,7 +703,6 @@ template <typename Type>
 struct BEInt<Type, 3>
 {
   public:
-  typedef Type type;
   void set (Type V)
   {
     v[0] = (V >> 16) & 0xFF;
diff --git a/src/hb-null.hh b/src/hb-null.hh
index 7ea2bab16..8a3e0d405 100644
--- a/src/hb-null.hh
+++ b/src/hb-null.hh
@@ -59,7 +59,10 @@ struct hb_null_size
 { enum { value = _hb_null_size<T, _hb_bool_type<true> >::value }; };
 #define hb_null_size(T) hb_null_size<T>::value
 
-/* This doesn't belong here, but since is copy/paste from above, put it here. */
+/* These doesn't belong here, but since is copy/paste from above, put it here. */
+
+/* hb_static_size (T)
+ * Returns T::static_size if T::min_size is defined, or sizeof (T) otherwise. */
 
 template <typename T, typename B>
 struct _hb_static_size
@@ -74,6 +77,25 @@ struct hb_static_size
 #define hb_static_size(T) hb_static_size<T>::value
 
 
+/* hb_assign (obj, value)
+ * Calls obj.set (value) if obj.min_size is defined and value has different type
+ * from obj, or obj = v otherwise. */
+
+template <typename T, typename V, typename B>
+struct _hb_assign
+{ static inline void value (T &o, const V v) { o = v; } };
+template <typename T, typename V>
+struct _hb_assign<T, V, _hb_bool_type<(bool) (1 + (unsigned int) T::min_size)> >
+{ static inline void value (T &o, const V v) { o.set (v); } };
+template <typename T>
+struct _hb_assign<T, T, _hb_bool_type<(bool) (1 + (unsigned int) T::min_size)> >
+{ static inline void value (T &o, const T v) { o = v; } };
+
+template <typename T, typename V>
+static inline void hb_assign (T &o, const V v)
+{ _hb_assign<T, V, _hb_bool_type<true> >::value (o, v); };
+
+
 /*
  * Null()
  */
diff --git a/src/hb-open-type.hh b/src/hb-open-type.hh
index 6517c6bfe..4c6d5e38b 100644
--- a/src/hb-open-type.hh
+++ b/src/hb-open-type.hh
@@ -352,7 +352,7 @@ static inline Type& operator + (Base &base, OffsetTo<Type, OffsetType, has_null>
 template <typename Type>
 struct UnsizedArrayOf
 {
-  typedef Type ItemType;
+  typedef Type item_t;
   enum { item_size = hb_static_size (Type) };
 
   HB_NO_CREATE_COPY_ASSIGN_TEMPLATE (UnsizedArrayOf, Type);
@@ -508,7 +508,7 @@ struct SortedUnsizedArrayOf : UnsizedArrayOf<Type>
 template <typename Type, typename LenType=HBUINT16>
 struct ArrayOf
 {
-  typedef Type ItemType;
+  typedef Type item_t;
   enum { item_size = hb_static_size (Type) };
 
   HB_NO_CREATE_COPY_ASSIGN_TEMPLATE2 (ArrayOf, Type, LenType);
@@ -553,12 +553,13 @@ struct ArrayOf
     if (unlikely (!c->extend (*this))) return_trace (false);
     return_trace (true);
   }
-  bool serialize (hb_serialize_context_t *c, hb_array_t<const Type> items)
+  template <typename T>
+  bool serialize (hb_serialize_context_t *c, hb_array_t<const T> items)
   {
     TRACE_SERIALIZE (this);
     if (unlikely (!serialize (c, items.len))) return_trace (false);
     for (unsigned int i = 0; i < items.len; i++)
-      arrayZ[i] = items[i];
+      hb_assign (arrayZ[i], items[i]);
     return_trace (true);
   }
 
diff --git a/src/hb-vector.hh b/src/hb-vector.hh
index d8e3f4ef1..4e962d2ef 100644
--- a/src/hb-vector.hh
+++ b/src/hb-vector.hh
@@ -34,7 +34,7 @@
 template <typename Type, unsigned int PreallocedCount=8>
 struct hb_vector_t
 {
-  typedef Type ItemType;
+  typedef Type item_t;
   enum { item_size = hb_static_size (Type) };
 
   HB_NO_COPY_ASSIGN_TEMPLATE2 (hb_vector_t, Type, PreallocedCount);
@@ -89,6 +89,8 @@ struct hb_vector_t
     return arrayZ()[i];
   }
 
+  explicit_operator bool () const { return len; }
+
   hb_array_t<Type> as_array ()
   { return hb_array (arrayZ(), len); }
   hb_array_t<const Type> as_array () const
diff --git a/src/hb-version.h b/src/hb-version.h
index 7c4a8ad4a..0c82d5bbb 100644
--- a/src/hb-version.h
+++ b/src/hb-version.h
@@ -37,10 +37,10 @@ HB_BEGIN_DECLS
 
 
 #define HB_VERSION_MAJOR 2
-#define HB_VERSION_MINOR 2
+#define HB_VERSION_MINOR 3
 #define HB_VERSION_MICRO 0
 
-#define HB_VERSION_STRING "2.2.0"
+#define HB_VERSION_STRING "2.3.0"
 
 #define HB_VERSION_ATLEAST(major,minor,micro) \
 	((major)*10000+(minor)*100+(micro) <= \
diff --git a/src/test-iter.cc b/src/test-iter.cc
new file mode 100644
index 000000000..32fb9f831
--- /dev/null
+++ b/src/test-iter.cc
@@ -0,0 +1,97 @@
+/*
+ * 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
+ */
+
+#include "hb-iter.hh"
+
+#include "hb-array.hh"
+
+template <typename T>
+struct array_iter_t : hb_iter_t<array_iter_t<T>, T>
+{
+  array_iter_t (hb_array_t<T> arr_) : arr (arr_) {}
+
+  typedef T __item_type__;
+  T& __item_at__ (unsigned i) const { return arr[i]; }
+  bool __more__ () const { return arr.len; }
+  void __forward__ (unsigned n) { arr += n; }
+  void __rewind__ (unsigned n) { arr -= n; }
+  unsigned __len__ () const { return arr.len; }
+
+  private:
+  hb_array_t<T> arr;
+};
+
+template <typename T>
+struct some_array_t
+{
+  some_array_t (hb_array_t<T> arr_) : arr (arr_) {}
+
+  typedef array_iter_t<T> iter_t;
+  array_iter_t<T> iter () { return array_iter_t<T> (arr); }
+  operator array_iter_t<T> () { return iter (); }
+  operator hb_iter_t<array_iter_t<T> > () { return iter (); }
+
+  private:
+  hb_array_t<T> arr;
+};
+
+
+template <typename I, typename V> inline void
+hb_fill (hb_iter_t<I> &i, const V &v)
+{
+  for (; i; i++)
+    hb_assign (*i, v);
+}
+
+template <typename S, typename D> inline bool
+hb_copy (hb_iter_t<D> &id, hb_iter_t<S> &is)
+{
+  for (; id && is; ++id, ++is)
+    *id = *is;
+  return !id;
+}
+
+int
+main (int argc, char **argv)
+{
+  const int src[10] = {};
+  int dst[20];
+  hb_vector_t<int> v;
+
+  array_iter_t<const int> s (src); /* Implicit conversion from static array. */
+  array_iter_t<const int> s2 (v); /* Implicit conversion from vector. */
+  array_iter_t<int> t (dst);
+
+  some_array_t<const int> a (src);
+
+  s2 = s;
+
+  hb_fill (t, 42);
+  hb_copy (t, s);
+ // hb_copy (t, a.iter ());
+
+  return 0;
+}
diff --git a/src/test-unicode-ranges.cc b/src/test-unicode-ranges.cc
index ec9d17acd..d5d39b957 100644
--- a/src/test-unicode-ranges.cc
+++ b/src/test-unicode-ranges.cc
@@ -24,8 +24,6 @@
  * Google Author(s): Garret Rieger
  */
 
-#include "hb.hh"
-
 #include "hb-ot-os2-unicode-ranges.hh"
 
 static void