diff --git a/extra/js17/PKGBUILD b/extra/js17/PKGBUILD
new file mode 100644
index 000000000..e76a85bd7
--- /dev/null
+++ b/extra/js17/PKGBUILD
@@ -0,0 +1,47 @@
+# $Id: PKGBUILD 183635 2013-04-25 18:13:54Z ioni $
+# Maintainer: Ionut Biru <ibiru@archlinux.org>
+
+# ALARM: Kevin Mihelich <kevin@archlinuxarm.org>
+#  - patch for AArch64
+
+pkgname=js17
+pkgver=17.0.0
+pkgrel=1
+pkgdesc="JavaScript interpreter and libraries (legacy)"
+arch=(i686 x86_64)
+url="https://developer.mozilla.org/En/SpiderMonkey/17"
+license=(MPL)
+depends=(nspr gcc-libs readline)
+makedepends=(python2 zip libffi)
+conflicts=('js<24.2.0')
+options=(!staticlibs)
+source=(http://ftp.mozilla.org/pub/mozilla.org/js/mozjs$pkgver.tar.gz
+        aarch64.patch)
+md5sums=('20b6f8f1140ef6e47daa3b16965c9202'
+         '144736bd4a4825ba5a1c87439230964d')
+
+prepare() {
+  cd mozjs$pkgver
+  patch -p1 -i ../aarch64.patch
+}
+
+build() {
+  unset CPPFLAGS
+  cd mozjs$pkgver/js/src
+  ./configure --prefix=/usr --with-system-nspr --with-system-ffi \
+     --enable-readline --enable-threadsafe
+  make
+}
+
+check() {
+  cd mozjs$pkgver/js/src
+  make check
+}
+
+package() {
+  cd mozjs$pkgver/js/src
+  make DESTDIR="$pkgdir" install
+  find "$pkgdir"/usr/{lib/pkgconfig,include} -type f -exec chmod -x {} +
+}
+
+# vim:set ts=2 sw=2 et:
diff --git a/extra/js17/aarch64.patch b/extra/js17/aarch64.patch
new file mode 100644
index 000000000..b7dec4a2d
--- /dev/null
+++ b/extra/js17/aarch64.patch
@@ -0,0 +1,13 @@
+diff -urN a/mfbt/double-conversion/utils.h b/mfbt/double-conversion/utils.h
+--- a/mfbt/double-conversion/utils.h	2013-10-29 14:40:19.000000000 -0600
++++ b/mfbt/double-conversion/utils.h	2015-07-10 22:55:40.262596161 -0600
+@@ -58,7 +58,8 @@
+     defined(__mips__) || defined(__powerpc__) || \
+     defined(__sparc__) || defined(__sparc) || defined(__s390__) || \
+     defined(__SH4__) || defined(__alpha__) || \
+-    defined(_MIPS_ARCH_MIPS32R2)
++    defined(_MIPS_ARCH_MIPS32R2) || \
++    defined(__AARCH64EL__)
+ #define DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS 1
+ #elif defined(_M_IX86) || defined(__i386__) || defined(__i386)
+ #if defined(_WIN32)