diff --git a/package.json b/package.json
index 83bdb52..6b81a32 100644
--- a/package.json
+++ b/package.json
@@ -28,7 +28,7 @@
   "devDependencies": {
     "broccoli": "^0.16.9",
     "broccoli-asset-rev": "^2.4.5",
-    "chai": "^3.5.0",
+    "chai": "^4.1.2",
     "ember-cli": "~3.0.1",
     "ember-cli-babel": "^6.7.1",
     "ember-cli-content-security-policy": "^0.4.0",
diff --git a/yarn.lock b/yarn.lock
index 8e252b1..b2ef8c9 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1498,13 +1498,16 @@ center-align@^0.1.1:
     align-text "^0.1.3"
     lazy-cache "^1.0.3"
 
-chai@^3.5.0:
-  version "3.5.0"
-  resolved "https://registry.yarnpkg.com/chai/-/chai-3.5.0.tgz#4d02637b067fe958bdbfdd3a40ec56fef7373247"
+chai@^4.1.2:
+  version "4.1.2"
+  resolved "https://registry.yarnpkg.com/chai/-/chai-4.1.2.tgz#0f64584ba642f0f2ace2806279f4f06ca23ad73c"
   dependencies:
     assertion-error "^1.0.1"
-    deep-eql "^0.1.3"
-    type-detect "^1.0.0"
+    check-error "^1.0.1"
+    deep-eql "^3.0.0"
+    get-func-name "^2.0.0"
+    pathval "^1.0.0"
+    type-detect "^4.0.0"
 
 chalk@^0.5.1:
   version "0.5.1"
@@ -1568,6 +1571,10 @@ charm@^1.0.0:
   dependencies:
     inherits "^2.0.1"
 
+check-error@^1.0.1:
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/check-error/-/check-error-1.0.2.tgz#574d312edd88bb5dd8912e9286dd6c0aed4aac82"
+
 chokidar@1.7.0:
   version "1.7.0"
   resolved "https://registry.yarnpkg.com/chokidar/-/chokidar-1.7.0.tgz#798e689778151c8076b4b360e5edd28cda2bb468"
@@ -1983,11 +1990,11 @@ decompress-response@^3.3.0:
   dependencies:
     mimic-response "^1.0.0"
 
-deep-eql@^0.1.3:
-  version "0.1.3"
-  resolved "https://registry.yarnpkg.com/deep-eql/-/deep-eql-0.1.3.tgz#ef558acab8de25206cd713906d74e56930eb69f2"
+deep-eql@^3.0.0:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/deep-eql/-/deep-eql-3.0.1.tgz#dfc9404400ad1c8fe023e7da1df1c147c4b444df"
   dependencies:
-    type-detect "0.1.1"
+    type-detect "^4.0.0"
 
 deep-extend@~0.4.0:
   version "0.4.2"
@@ -3222,6 +3229,10 @@ get-caller-file@^1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/get-caller-file/-/get-caller-file-1.0.2.tgz#f702e63127e7e231c160a80c1554acb70d5047e5"
 
+get-func-name@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/get-func-name/-/get-func-name-2.0.0.tgz#ead774abee72e20409433a066366023dd6887a41"
+
 get-stdin@^4.0.1:
   version "4.0.1"
   resolved "https://registry.yarnpkg.com/get-stdin/-/get-stdin-4.0.1.tgz#b968c6b0a04384324902e8bf1a5df32579a450fe"
@@ -5369,6 +5380,10 @@ path-type@^3.0.0:
   dependencies:
     pify "^3.0.0"
 
+pathval@^1.0.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/pathval/-/pathval-1.1.0.tgz#b942e6d4bde653005ef6b71361def8727d0645e0"
+
 performance-now@^0.2.0:
   version "0.2.0"
   resolved "https://registry.yarnpkg.com/performance-now/-/performance-now-0.2.0.tgz#33ef30c5c77d4ea21c5a53869d91b56d8f2555e5"
@@ -6784,13 +6799,9 @@ type-check@~0.3.2:
   dependencies:
     prelude-ls "~1.1.2"
 
-type-detect@0.1.1:
-  version "0.1.1"
-  resolved "https://registry.yarnpkg.com/type-detect/-/type-detect-0.1.1.tgz#0ba5ec2a885640e470ea4e8505971900dac58822"
-
-type-detect@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/type-detect/-/type-detect-1.0.0.tgz#762217cc06db258ec48908a1298e8b95121e8ea2"
+type-detect@^4.0.0:
+  version "4.0.8"
+  resolved "https://registry.yarnpkg.com/type-detect/-/type-detect-4.0.8.tgz#7646fb5f18871cfbb7749e69bd39a6388eb7450c"
 
 type-is@~1.6.15:
   version "1.6.16"