diff --git a/gentoo/chromium-53.0.2785.92.ebuild b/chromium-53.0.2785.92.ebuild
index 9290132..c6558f3 100644
--- a/gentoo/chromium-53.0.2785.92.ebuild
+++ b/chromium-53.0.2785.92.ebuild
@@ -18,11 +18,11 @@ SRC_URI="https://commondatastorage.googleapis.com/chromium-browser-official/${P}
 LICENSE="BSD"
 SLOT="0"
 KEYWORDS="amd64 ~arm ~arm64 x86"
-IUSE="cups gn gnome gnome-keyring gtk3 +hangouts kerberos neon pic +proprietary-codecs pulseaudio selinux +system-ffmpeg +tcmalloc widevine"
+IUSE="cups gn gnome gnome-keyring gtk3 +hangouts kerberos nacl neon pic +proprietary-codecs pulseaudio selinux +system-ffmpeg +tcmalloc widevine"
 RESTRICT="!system-ffmpeg? ( proprietary-codecs? ( bindist ) )"
 
 # TODO: bootstrapped gn binary hangs when using tcmalloc with portage's sandbox.
-REQUIRED_USE="gn? ( gnome gnome-keyring !tcmalloc )"
+REQUIRED_USE="gn? ( gnome gnome-keyring !tcmalloc ) arm? ( !nacl )"
 
 # Native Client binaries are compiled with different set of flags, bug #452066.
 QA_FLAGS_IGNORED=".*\.nexe"
@@ -187,6 +187,12 @@ pkg_setup() {
 }
 
 src_prepare() {
+    if use nacl; then
+        python build/download_nacl_toolchains.py \
+            --packages nacl_x86_newlib,pnacl_newlib,pnacl_translator \
+        sync --extract
+    fi
+
 	epatch "${FILESDIR}/${PN}-system-ffmpeg-r2.patch"
 	epatch "${FILESDIR}/${PN}-system-jinja-r11.patch"
 	epatch "${FILESDIR}/${PN}-widevine-r1.patch"
@@ -320,6 +326,8 @@ src_prepare() {
 		'url/third_party/mozilla' \
 		'v8/src/third_party/fdlibm' \
 		'v8/src/third_party/valgrind' \
+		'base/third_party/libevent' \
+		'native_client/src/third_party/dlmalloc' \
 		--do-remove || die
 }
 
@@ -334,9 +342,14 @@ src_configure() {
 	# additions, bug #336871.
 	myconf_gyp+=" -Ddisable_sse2=1"
 
-	# Disable nacl, we can't build without pnacl (http://crbug.com/269560).
-	myconf_gyp+=" -Ddisable_nacl=1"
-	myconf_gn+=" enable_nacl=false"
+	if ! use nacl ; then
+		myconf_gyp+=" -Ddisable_nacl=1"
+		myconf_gn+=" enable_nacl=false"
+	else
+		myconf_gyp+=" -Ddisable_glibc=1"
+		myconf_gn+=" enable_glibc=false"
+	fi
+
 
 	# Make it possible to remove third_party/adobe.
 	echo > "${T}/flapper_version.h" || die
@@ -622,12 +635,12 @@ src_install() {
 	doexe out/Release/chromedriver || die
 	use widevine && doexe out/Release/libwidevinecdmadapter.so
 
-	# if ! use arm; then
-	#	doexe out/Release/nacl_helper{,_bootstrap} || die
-	#	insinto "${CHROMIUM_HOME}"
-	#	doins out/Release/nacl_irt_*.nexe || die
-	#	doins out/Release/libppGoogleNaClPluginChrome.so || die
-	# fi
+	if use nacl; then
+		doexe out/Release/nacl_helper{,_bootstrap} || die
+		insinto "${CHROMIUM_HOME}"
+		doins out/Release/nacl_irt_*.nexe || die
+	fi
+
 
 	local sedargs=( -e "s:/usr/lib/:/usr/$(get_libdir)/:g" )
 	if [[ -n ${CHROMIUM_SUFFIX} ]]; then