diff --git a/lib/levels/nested.js b/lib/levels/nested.js
index <HASH>..<HASH> 100644
--- a/lib/levels/nested.js
+++ b/lib/levels/nested.js
@@ -1,3 +1,5 @@
+'use strict';
+
 var INHERIT = require('inherit'),
     PATH = require('../path'),
     Level = require('../level').Level,
diff --git a/lib/levels/project.js b/lib/levels/project.js
index <HASH>..<HASH> 100644
--- a/lib/levels/project.js
+++ b/lib/levels/project.js
@@ -1,3 +1,5 @@
+'use strict';
+
 exports.baseLevelPath = require.resolve('./simple');
 
 exports.getTypes = function() {
diff --git a/lib/levels/simple.js b/lib/levels/simple.js
index <HASH>..<HASH> 100644
--- a/lib/levels/simple.js
+++ b/lib/levels/simple.js
@@ -1,3 +1,5 @@
+'use strict';
+
 var INHERIT = require('inherit'),
     Level = require('../level').Level,
     U = require('../util');
@@ -114,7 +116,7 @@ exports.Level = INHERIT(Level, {
                     block: block,
                     suffix: suffix,
                     tech: this.suffixToTech[suffix]
-                }
+                };
 
             file = file.substring(0, dot);
Fix jshint errors in lib/levels/