diff --git a/.eslintrc.json b/.eslintrc.json
index df70b9f..9a84f13 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -89,6 +89,10 @@
 	],
 	"brace-style": [
 		"error"
+	],
+	"strict": [
+		"error",
+		"global"
 	]
     }
 }
diff --git a/gulpfile.js b/gulpfile.js
index a8e05be..3a625df 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const del = require('del');
 const gulp = require('gulp');
 const postcss = require('gulp-postcss');
diff --git a/lib/handlebarsHelpers.js b/lib/handlebarsHelpers.js
index 88bd8f2..17c1ea7 100644
--- a/lib/handlebarsHelpers.js
+++ b/lib/handlebarsHelpers.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const helpers = {};
 
 helpers.eq = (arg1, arg2, options) =>
diff --git a/routes/admin.js b/routes/admin.js
index 84b1ec6..1f3fbac 100644
--- a/routes/admin.js
+++ b/routes/admin.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const express = require('express');
 const router = express.Router();
 
diff --git a/routes/class.js b/routes/class.js
index 9703652..75d1af1 100644
--- a/routes/class.js
+++ b/routes/class.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const express = require('express');
 const router = express.Router();
 
diff --git a/routes/main.js b/routes/main.js
index ed908ec..160c24f 100644
--- a/routes/main.js
+++ b/routes/main.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const express = require('express');
 const router = express.Router();
 
diff --git a/routes/report.js b/routes/report.js
index 9111870..325571b 100644
--- a/routes/report.js
+++ b/routes/report.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const express = require('express');
 const router = express.Router();
 
diff --git a/routes/test.js b/routes/test.js
index 0d1d991..8e3cb51 100644
--- a/routes/test.js
+++ b/routes/test.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const express = require('express');
 const router = express.Router();