diff --git a/package-lock.json b/package-lock.json
index bcf6121..264e44e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -44,9 +44,9 @@
       "dev": true
     },
     "assertion-error": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-1.0.0.tgz",
-      "integrity": "sha1-x/hUOP3UZrx8oWq5DIFRN5el0js=",
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-1.1.0.tgz",
+      "integrity": "sha512-jgsaNduz+ndvGyFt3uSuWqvy4lCnIJiovtouQN5JZHOKCS2QuhEdbcQHFhVksz2N2U9hXJo8odG7ETyWlEeuDw==",
       "dev": true
     },
     "async": {
@@ -180,13 +180,17 @@
       "dev": true
     },
     "chai": {
-      "version": "2.3.0",
-      "resolved": "https://registry.npmjs.org/chai/-/chai-2.3.0.tgz",
-      "integrity": "sha1-ii9qNHSNqAEJD9cyh7Kqc5pOkJo=",
+      "version": "4.2.0",
+      "resolved": "https://registry.npmjs.org/chai/-/chai-4.2.0.tgz",
+      "integrity": "sha512-XQU3bhBukrOsQCuwZndwGcCVQHyZi53fQ6Ys1Fym7E4olpIqqZZhhoFJoaKVvV17lWQoXYwgWN2nF5crA8J2jw==",
       "dev": true,
       "requires": {
-        "assertion-error": "1.0.0",
-        "deep-eql": "0.1.3"
+        "assertion-error": "1.1.0",
+        "check-error": "1.0.2",
+        "deep-eql": "3.0.1",
+        "get-func-name": "2.0.0",
+        "pathval": "1.1.0",
+        "type-detect": "4.0.8"
       }
     },
     "chalk": {
@@ -202,6 +206,12 @@
         "supports-color": "2.0.0"
       }
     },
+    "check-error": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/check-error/-/check-error-1.0.2.tgz",
+      "integrity": "sha1-V00xLt2Iu13YkS6Sht1sCu1KrII=",
+      "dev": true
+    },
     "cline": {
       "version": "0.8.2",
       "resolved": "https://registry.npmjs.org/cline/-/cline-0.8.2.tgz",
@@ -438,12 +448,12 @@
       }
     },
     "deep-eql": {
-      "version": "0.1.3",
-      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-0.1.3.tgz",
-      "integrity": "sha1-71WKyrjeJSBs1xOQbXTlaTDrafI=",
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-3.0.1.tgz",
+      "integrity": "sha512-+QeIQyN5ZuO+3Uk5DYh6/1eKO0m0YmJFGNmFHGACpf1ClL1nmlV/p4gNgbl2pJGxgXb4faqo6UE+M5ACEMyVcw==",
       "dev": true,
       "requires": {
-        "type-detect": "0.1.1"
+        "type-detect": "4.0.8"
       }
     },
     "depd": {
@@ -666,6 +676,12 @@
       "integrity": "sha1-FQStJSMVjKpA20onh8sBQRmU6k8=",
       "dev": true
     },
+    "get-func-name": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/get-func-name/-/get-func-name-2.0.0.tgz",
+      "integrity": "sha1-6td0q+5y4gQJQzoGY2YCPdaIekE=",
+      "dev": true
+    },
     "glob": {
       "version": "3.2.11",
       "resolved": "https://registry.npmjs.org/glob/-/glob-3.2.11.tgz",
@@ -1153,6 +1169,12 @@
       "integrity": "sha1-F0uSaHNVNP+8es5r9TpanhtcX18=",
       "dev": true
     },
+    "pathval": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/pathval/-/pathval-1.1.0.tgz",
+      "integrity": "sha1-uULm1L3mUwBe9rcTYd74cn0GReA=",
+      "dev": true
+    },
     "pause": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/pause/-/pause-0.1.0.tgz",
@@ -1496,9 +1518,9 @@
       "dev": true
     },
     "type-detect": {
-      "version": "0.1.1",
-      "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-0.1.1.tgz",
-      "integrity": "sha1-C6XsKohWQORw6k6FBZcZANrFiCI=",
+      "version": "4.0.8",
+      "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-4.0.8.tgz",
+      "integrity": "sha512-0fr/mIH1dlO+x7TlcMy+bIDqKPsw/70tVyeHW787goQjhmqaZe10uwLujubK9q9Lg6Fiho1KUKDYz0Z7k7g5/g==",
       "dev": true
     },
     "type-is": {
diff --git a/package.json b/package.json
index bf53dfd..2a345f7 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   },
   "devDependencies": {
     "bluebird": "^3.5.1",
-    "chai": "^2.1.1",
+    "chai": "^4.2.0",
     "co": "^4.6.0",
     "coffee-script": "^1.12.7",
     "hubot": "2.x",