diff --git a/appengine/errorreporting/package.json b/appengine/errorreporting/package.json
index f23b26a833..0a25f492d2 100644
--- a/appengine/errorreporting/package.json
+++ b/appengine/errorreporting/package.json
@@ -29,7 +29,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "test": {
diff --git a/endpoints/getting-started/package.json b/endpoints/getting-started/package.json
index b7e0e802ba..e514a564a9 100644
--- a/endpoints/getting-started/package.json
+++ b/endpoints/getting-started/package.json
@@ -28,7 +28,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2",
+    "sinon": "4.5.0",
     "supertest": "3.0.0"
   }
 }
diff --git a/error-reporting/package.json b/error-reporting/package.json
index 596aa76211..3c59955cba 100644
--- a/error-reporting/package.json
+++ b/error-reporting/package.json
@@ -30,7 +30,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/background/package.json b/functions/background/package.json
index 4a28cd2681..318e7382e0 100644
--- a/functions/background/package.json
+++ b/functions/background/package.json
@@ -25,7 +25,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/composer-storage-trigger/package.json b/functions/composer-storage-trigger/package.json
index a26ae59992..0d99508b42 100644
--- a/functions/composer-storage-trigger/package.json
+++ b/functions/composer-storage-trigger/package.json
@@ -20,7 +20,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "scripts": {
     "lint": "semistandard '**/*.js'",
diff --git a/functions/datastore/package.json b/functions/datastore/package.json
index 93154d10ea..53fab80270 100644
--- a/functions/datastore/package.json
+++ b/functions/datastore/package.json
@@ -28,7 +28,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/env_vars/package.json b/functions/env_vars/package.json
index 8a94623b93..26f31f78fb 100644
--- a/functions/env_vars/package.json
+++ b/functions/env_vars/package.json
@@ -21,7 +21,7 @@
     "@google-cloud/nodejs-repo-tools": "^3.0.0",
     "ava": "0.25.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/firebase/package.json b/functions/firebase/package.json
index 61df993281..e968e77824 100644
--- a/functions/firebase/package.json
+++ b/functions/firebase/package.json
@@ -20,7 +20,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.1",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.8",
+    "sinon": "4.5.0",
     "supertest": "^3.0.0",
     "uuid": "^3.1.0"
   },
diff --git a/functions/gcs/package.json b/functions/gcs/package.json
index 502c88afeb..59cf57abc9 100644
--- a/functions/gcs/package.json
+++ b/functions/gcs/package.json
@@ -25,7 +25,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/helloworld/package.json b/functions/helloworld/package.json
index b932337a33..143a20437e 100644
--- a/functions/helloworld/package.json
+++ b/functions/helloworld/package.json
@@ -33,7 +33,7 @@
     "express": "^4.16.3",
     "proxyquire": "2.0.1",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.8",
+    "sinon": "4.5.0",
     "supertest": "^3.0.0",
     "uuid": "^3.1.0",
     "yargs": "^11.0.0"
diff --git a/functions/http/package.json b/functions/http/package.json
index cbdc744f5e..117fbcdbaf 100644
--- a/functions/http/package.json
+++ b/functions/http/package.json
@@ -21,7 +21,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "dependencies": {
     "@google-cloud/storage": "1.7.0",
diff --git a/functions/imagemagick/package.json b/functions/imagemagick/package.json
index 68d43e8125..129dd13ad5 100644
--- a/functions/imagemagick/package.json
+++ b/functions/imagemagick/package.json
@@ -26,7 +26,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/log/package.json b/functions/log/package.json
index f3502c23a7..19dbee5be2 100644
--- a/functions/log/package.json
+++ b/functions/log/package.json
@@ -25,7 +25,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/pubsub/package.json b/functions/pubsub/package.json
index 465fc782e6..2401709cff 100644
--- a/functions/pubsub/package.json
+++ b/functions/pubsub/package.json
@@ -25,7 +25,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/sendgrid/package.json b/functions/sendgrid/package.json
index 822882961a..5e365e97b6 100644
--- a/functions/sendgrid/package.json
+++ b/functions/sendgrid/package.json
@@ -28,7 +28,7 @@
     "ava": "0.25.0",
     "proxyquire": "1.8.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.0.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/slack/package.json b/functions/slack/package.json
index 6f97f48d76..7b0153ec77 100644
--- a/functions/slack/package.json
+++ b/functions/slack/package.json
@@ -24,7 +24,7 @@
     "ava": "0.25.0",
     "proxyquire": "1.8.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.0.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/spanner/package.json b/functions/spanner/package.json
index b236335c9c..50d6553197 100644
--- a/functions/spanner/package.json
+++ b/functions/spanner/package.json
@@ -24,7 +24,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/sql/package.json b/functions/sql/package.json
index 3513f79501..a6eaa166a1 100644
--- a/functions/sql/package.json
+++ b/functions/sql/package.json
@@ -30,7 +30,7 @@
     "ava": "0.25.0",
     "proxyquire": "^2.1.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/functions/uuid/package.json b/functions/uuid/package.json
index 1f707a31e7..8e714e3a89 100644
--- a/functions/uuid/package.json
+++ b/functions/uuid/package.json
@@ -23,7 +23,7 @@
     "@google-cloud/nodejs-repo-tools": "^3.0.0",
     "ava": "0.25.0",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.2"
+    "sinon": "4.5.0"
   },
   "cloud-repo-tools": {
     "requiresKeyFile": true,
diff --git a/storage-transfer/package.json b/storage-transfer/package.json
index 9194ac3258..4de70c9d32 100644
--- a/storage-transfer/package.json
+++ b/storage-transfer/package.json
@@ -30,7 +30,7 @@
     "ava": "0.25.0",
     "proxyquire": "2.0.1",
     "semistandard": "^12.0.1",
-    "sinon": "4.4.8",
+    "sinon": "4.5.0",
     "uuid": "3.3.2"
   },
   "cloud-repo-tools": {