diff --git a/unix/attrstr.c b/unix/attrstr.c
index 88eabef4..7bf556c9 100644
--- a/unix/attrstr.c
+++ b/unix/attrstr.c
@@ -10,7 +10,7 @@ struct foreachParams {
 	const char *s;
 	PangoAttrList *attrs;
 	// keys are pointers to size_t maintained by g_new0()/g_free()
-	// values are GStrings
+	// values are strings
 	GHashTable *features;
 	// TODO use pango's built-in background attribute?
 	GPtrArray *backgroundClosures;
@@ -38,24 +38,22 @@ static void freeFeatureString(gpointer s)
 
 #define isCodepointStart(b) (((uint8_t) (b)) <= 0x7F || ((uint8_t) (b)) >= 0xC0)
 
-static void ensureFeaturesInRange(struct foreachParams *p, size_t start, size_t end)
+static void setFeaturesInRange(struct foreachParams *p, size_t start, size_t end, uiOpenTypeFeatures *otf)
 {
 	size_t i;
 	size_t *key;
 	GString *new;
 
+	new = otfToPangoCSSString(otf);
 	for (i = start; i < end; i++) {
 		// don't create redundant entries; see below
 		if (!isCodepointStart(p->s[i]))
 			continue;
-		new = (GString *) g_hash_table_lookup(p->features, &i);
-		if (new != NULL)
-			continue;
-		new = g_string_new("");
 		key = g_new0(size_t, 1);
 		*key = i;
-		g_hash_table_replace(p->features, key, new);
+		g_hash_table_replace(p->features, key, g_strdup(new->str));
 	}
+	g_string_free(new, TRUE);
 }
 
 struct closureParams {
@@ -104,30 +102,6 @@ static GClosure *mkBackgroundClosure(size_t start, size_t end, double r, double
 	return closure;
 }
 
-struct otParam {
-	struct foreachParams *p;
-	size_t start;
-	size_t end;
-};
-
-// see https://developer.mozilla.org/en/docs/Web/CSS/font-feature-settings
-static void doOpenType(const char *featureTag, uint32_t param, void *data)
-{
-	struct otParam *p = (struct otParam *) data;
-	size_t i;
-	GString *s;
-
-	ensureFeaturesInRange(p->p, p->start, p->end);
-	for (i = p->start; i < p->end; i++) {
-		// don't use redundant entries; see below
-		if (!isCodepointStart(p->p->s[i]))
-			continue;
-		s = (GString *) g_hash_table_lookup(p->p->features, &i);
-		g_string_append_printf(s, "\"%s\" %" PRIu32 ", ",
-			featureTag, param);
-	}
-}
-
 static void addattr(struct foreachParams *p, size_t start, size_t end, PangoAttribute *attr)
 {
 	if (attr == NULL)		// in case of a future attribute
@@ -142,7 +116,6 @@ static int processAttribute(uiAttributedString *s, uiAttributeSpec *spec, size_t
 	struct foreachParams *p = (struct foreachParams *) data;
 	GClosure *closure;
 	PangoUnderline underline;
-	struct otParam op;
 
 	switch (spec->Type) {
 	case uiAttributeFamily:
@@ -225,14 +198,13 @@ static int processAttribute(uiAttributedString *s, uiAttributeSpec *spec, size_t
 			break;
 		}
 		break;
-	default:
-		// handle typographic features
-		op.p = p;
-		op.start = start;
-		op.end = end;
-		// TODO check if unhandled and complain
-		specToOpenType(spec, doOpenType, &op);
+	case uiAttributeFeatures:
+		// TODO ensure the parentheses around spec->Value are provided on Windows
+		setFeaturesInRange(p, start, end, (uiOpenTypeFeatures *) (spec->Value));
 		break;
+	default:
+		// TODO complain
+		;
 	}
 	return 0;
 }
@@ -241,18 +213,16 @@ static gboolean applyFeatures(gpointer key, gpointer value, gpointer data)
 {
 	struct foreachParams *p = (struct foreachParams *) data;
 	size_t *pos = (size_t *) key;
-	GString *s = (GString *) value;
+	char *s = (char *) value;
 	size_t n;
 
-	// remove the trailing comma/space
-	g_string_truncate(s, s->len - 2);
 	// make sure we cover an entire code point
 	// otherwise Pango will break apart multi-byte characters, spitting out U+FFFD characters at the invalid points
 	n = 1;
 	while (!isCodepointStart(p->s[*pos + n]))
 		n++;
 	addattr(p, *pos, *pos + n,
-		FUTURE_pango_attr_font_features_new(s->str));
+		FUTURE_pango_attr_font_features_new(s));
 	return TRUE;		// always delete; we're emptying the map
 }
 
@@ -275,7 +245,7 @@ PangoAttrList *attrstrToPangoAttrList(uiDrawTextLayoutParams *p, GPtrArray **bac
 	fep.attrs = pango_attr_list_new();
 	fep.features = g_hash_table_new_full(
 		featurePosHash, featurePosEqual,
-		g_free, freeFeatureString);
+		g_free, g_free);
 	fep.backgroundClosures = g_ptr_array_new_with_free_func(unrefClosure);
 	uiAttributedStringForEachAttribute(p->String, processAttribute, &fep);
 	applyAndFreeFeatureAttributes(&fep);
diff --git a/unix/opentype.c b/unix/opentype.c
index 12869a6a..6ea317c5 100644
--- a/unix/opentype.c
+++ b/unix/opentype.c
@@ -1,7 +1,7 @@
 // 11 may 2017
-#include "uipriv_windows.hpp"
+#include "uipriv_unix.h"
 
-// TODO switch from GINT_FROM_POINTER() and so to a fake GUINT_FROM_POINTER()?
+// TODO switch from GINT_TO_POINTER() and so to a fake GUINT_TO_POINTER()?
 
 struct uiOpenTypeFeatures {
 	GHashTable *tags;
@@ -106,9 +106,9 @@ void uiOpenTypeFeaturesForEach(uiOpenTypeFeatures *otf, uiOpenTypeFeaturesForEac
 	g_hash_table_foreach(otf->tags, foreach, &ofe);
 }
 
-static gint tagcmp(gpointer a, gpointer b)
+static gint tagcmp(gconstpointer a, gconstpointer b)
 {
-	return GINT_FROM_POINTER(a) - GINT_FROM_POINTER(b);
+	return GPOINTER_TO_INT(a) - GPOINTER_TO_INT(b);
 }
 
 static GList *copySortedKeys(GHashTable *tags)
@@ -130,8 +130,8 @@ int uiOpenTypeFeaturesEqual(uiOpenTypeFeatures *a, uiOpenTypeFeatures *b)
 	guint i;
 	int equal = 0;
 
-	ak = copySortedKeys(a);
-	bk = copySortedKeys(b);
+	ak = copySortedKeys(a->tags);
+	bk = copySortedKeys(b->tags);
 
 	na = g_list_length(ak);
 	nb = g_list_length(bk);
@@ -140,7 +140,7 @@ int uiOpenTypeFeaturesEqual(uiOpenTypeFeatures *a, uiOpenTypeFeatures *b)
 		goto out;
 	}
 
-	// TODO use GINT_FROM_POINTER() in these?
+	// TODO use GPOINTER_TO_INT() in these?
 	ai = ak;
 	bi = bk;
 	for (i = 0; i < na; i++) {
@@ -153,8 +153,8 @@ int uiOpenTypeFeaturesEqual(uiOpenTypeFeatures *a, uiOpenTypeFeatures *b)
 			goto out;
 		}
 		// and compare values
-		av = g_hash_table_lookup(a, ai->data);
-		bv = g_hash_table_lookup(b, bi->data);
+		av = g_hash_table_lookup(a->tags, ai->data);
+		bv = g_hash_table_lookup(b->tags, bi->data);
 		if (av != bv) {
 			equal = 0;
 			goto out;
@@ -172,6 +172,7 @@ out:
 	return equal;
 }
 
+// see https://developer.mozilla.org/en/docs/Web/CSS/font-feature-settings
 // TODO make this a g_hash_table_foreach() function (which requires duplicating code)?
 static int toCSS(char a, char b, char c, char d, uint32_t value, void *data)
 {
diff --git a/unix/uipriv_unix.h b/unix/uipriv_unix.h
index bde6502f..cb5bf281 100644
--- a/unix/uipriv_unix.h
+++ b/unix/uipriv_unix.h
@@ -71,3 +71,6 @@ extern void invokeBackgroundClosure(GClosure *closure, uiDrawContext *c, uiDrawT
 #define cairoToPango(cairo) (pango_units_from_double(cairo))
 extern const PangoStyle pangoItalics[];
 extern const PangoStretch pangoStretches[];
+
+// opentype.c
+extern GString *otfToPangoCSSString(uiOpenTypeFeatures *otf);