diff --git a/package-lock.json b/package-lock.json
index 14aaa8f..70780f6 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -216,9 +216,9 @@
       }
     },
     "@types/debug": {
-      "version": "0.0.30",
-      "resolved": "https://registry.npmjs.org/@types/debug/-/debug-0.0.30.tgz",
-      "integrity": "sha512-orGL5LXERPYsLov6CWs3Fh6203+dXzJkR7OnddIr2514Hsecwc8xRpzCapshBbKFImCsvS/mk6+FWiN5LyZJAQ==",
+      "version": "0.0.31",
+      "resolved": "https://registry.npmjs.org/@types/debug/-/debug-0.0.31.tgz",
+      "integrity": "sha512-LS1MCPaQKqspg7FvexuhmDbWUhE2yIJ+4AgVIyObfc06/UKZ8REgxGNjZc82wPLWmbeOm7S+gSsLgo75TanG4A==",
       "dev": true
     },
     "@types/express": {
@@ -1420,6 +1420,7 @@
           "version": "0.1.4",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "kind-of": "^3.0.2",
             "longest": "^1.0.1",
@@ -2362,7 +2363,8 @@
         "longest": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "lru-cache": {
           "version": "4.1.3",
diff --git a/package.json b/package.json
index 7da3e7d..d60ffd4 100644
--- a/package.json
+++ b/package.json
@@ -20,7 +20,7 @@
   },
   "devDependencies": {
     "@types/chai": "^4.0.4",
-    "@types/debug": "^0.0.30",
+    "@types/debug": "^0.0.31",
     "@types/express": "^4.0.39",
     "@types/mocha": "^5.0.0",
     "@types/request": "^2.0.8",