diff --git a/package-lock.json b/package-lock.json
index 7064f2f..3dd0ae1 100644
--- a/package-lock.json
+++ b/package-lock.json
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+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/vary/-/vary-1.1.2.tgz",
+      "integrity": "sha1-IpnwLG3tMNSllhsLn3RSShj2NPw=",
+      "dev": true
+    },
     "verror": {
       "version": "1.10.0",
       "resolved": "https://registry.npmjs.org/verror/-/verror-1.10.0.tgz",
diff --git a/package.json b/package.json
index 6afe0fc..975ae6b 100644
--- a/package.json
+++ b/package.json
@@ -41,6 +41,7 @@
     "karma-sinon": "^1.0.5",
     "karma-sourcemap-loader": "^0.3.7",
     "karma-webpack": "^3.0.5",
+    "lanthan": "git+https://github.com/ueokande/lanthan.git#master",
     "mocha": "^6.0.2",
     "node-sass": "^4.11.0",
     "power-assert": "^1.6.1",