diff --git a/debian/changelog b/debian/changelog
index c271ff80..1eac49c4 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -9,6 +9,8 @@ ostree (2017.11-1) UNRELEASED; urgency=medium
     into source tree. Upstream distributes it again.
   * Add a patch to fix the new test-help.sh when ostree trivial-httpd
     is enabled. At the moment we still build that tool.
+  * Add a patch to fix JavaScript tests with gjs 1.50.0, which is
+    more strict about 'let'
 
  -- Simon McVittie <smcv@debian.org>  Wed, 30 Aug 2017 10:09:26 +0100
 
diff --git a/debian/patches/Fix-JavaScript-tests-with-gjs-1.50.0.patch b/debian/patches/Fix-JavaScript-tests-with-gjs-1.50.0.patch
new file mode 100644
index 00000000..f92ff12e
--- /dev/null
+++ b/debian/patches/Fix-JavaScript-tests-with-gjs-1.50.0.patch
@@ -0,0 +1,42 @@
+From: Simon McVittie <smcv@collabora.com>
+Date: Fri, 15 Sep 2017 15:32:55 +0100
+Subject: Fix JavaScript tests with gjs 1.50.0
+
+In recent gjs, you can't declare a variable with "let" multiple times.
+
+Signed-off-by: Simon McVittie <smcv@collabora.com>
+---
+ tests/corrupt-repo-ref.js | 2 +-
+ tests/test-sysroot.js     | 6 +++---
+ 2 files changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/tests/corrupt-repo-ref.js b/tests/corrupt-repo-ref.js
+index c5f2806..a2085f3 100755
+--- a/tests/corrupt-repo-ref.js
++++ b/tests/corrupt-repo-ref.js
+@@ -47,7 +47,7 @@ function listObjectChecksumsRecurse(dir, allObjects) {
+     e.close(null);
+ } 
+ 
+-let [,commit] = repo.resolve_rev(refToCorrupt, false);
++repo.resolve_rev(refToCorrupt, false);
+ let [,root,commit] = repo.read_commit(refToCorrupt, null);
+ let allObjects = {};
+ allObjects[commit + '.commit'] = true;
+diff --git a/tests/test-sysroot.js b/tests/test-sysroot.js
+index 40397fe..e7250a8 100755
+--- a/tests/test-sysroot.js
++++ b/tests/test-sysroot.js
+@@ -97,9 +97,9 @@ assertEquals(deploymentPath.query_exists(null), false);
+ 
+ //// Ok, redeploy, then add a new revision upstream and pull it
+ 
+-let [,deployment] = sysroot.deploy_tree('testos', rev, origin,
+-					mergeDeployment, null,
+-					null);
++[,deployment] = sysroot.deploy_tree('testos', rev, origin,
++				 mergeDeployment, null,
++				 null);
+ newDeployments = deployments;
+ deployments = null;
+ newDeployments.unshift(deployment);
diff --git a/debian/patches/series b/debian/patches/series
index 913d54ed..9c0cba77 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -1 +1,2 @@
 Fix-test-help.sh-for-the-case-where-ostree-trivial-httpd-.patch
+Fix-JavaScript-tests-with-gjs-1.50.0.patch