diff --git a/snippets/jenkins/index.js b/snippets/jenkins/index.js
index 7c28e69..b76ac71 100644
--- a/snippets/jenkins/index.js
+++ b/snippets/jenkins/index.js
@@ -8,6 +8,8 @@
 /* eslint-disable no-sync */
 /* eslint-disable no-console */
 
+'use strict';
+
 const fs = require ('fs-extra');
 const path = require ('path');
 
diff --git a/snippets/migration/index.js b/snippets/migration/index.js
index 14545ff..a1f39b4 100644
--- a/snippets/migration/index.js
+++ b/snippets/migration/index.js
@@ -8,6 +8,8 @@
 /* eslint-disable no-sync */
 /* eslint-disable no-console */
 
+'use strict';
+
 const fs = require ('fs-extra');
 const path = require ('path');
 
diff --git a/snippets/migration/template.js b/snippets/migration/template.js
index dbb8383..d48e853 100644
--- a/snippets/migration/template.js
+++ b/snippets/migration/template.js
@@ -1,5 +1,7 @@
 /* eslint-disable no-magic-numbers */
 
+'use strict';
+
 /**
  * execute migration
  *
diff --git a/snippets/node/index.js b/snippets/node/index.js
index 30ecbbf..882873e 100644
--- a/snippets/node/index.js
+++ b/snippets/node/index.js
@@ -8,6 +8,8 @@
 /* eslint-disable no-sync */
 /* eslint-disable no-console */
 
+'use strict';
+
 const fs = require ('fs-extra');
 const path = require ('path');
 const child_process = require ('child_process');
diff --git a/snippets/requestor/index.js b/snippets/requestor/index.js
index da67176..b542602 100644
--- a/snippets/requestor/index.js
+++ b/snippets/requestor/index.js
@@ -8,6 +8,8 @@
 /* eslint-disable no-sync */
 /* eslint-disable no-console */
 
+'use strict';
+
 const fs = require ('fs-extra');
 const path = require ('path');
 
diff --git a/snippets/requestor/template.js b/snippets/requestor/template.js
index 6277a75..719504b 100644
--- a/snippets/requestor/template.js
+++ b/snippets/requestor/template.js
@@ -1,3 +1,5 @@
+'use strict';
+
 module.exports = function handler (req, res, next, opts) {
   if (req.headers.example === 'abc')
     res.writeHead (1);
diff --git a/snippets/snippet/index.js b/snippets/snippet/index.js
index da2903c..45bba7f 100644
--- a/snippets/snippet/index.js
+++ b/snippets/snippet/index.js
@@ -8,6 +8,8 @@
 /* eslint-disable no-sync */
 /* eslint-disable no-console */
 
+'use strict';
+
 const fs = require ('fs-extra');
 const path = require ('path');
 
diff --git a/snippets/snippet/template/index.js b/snippets/snippet/template/index.js
index da2903c..45bba7f 100644
--- a/snippets/snippet/template/index.js
+++ b/snippets/snippet/template/index.js
@@ -8,6 +8,8 @@
 /* eslint-disable no-sync */
 /* eslint-disable no-console */
 
+'use strict';
+
 const fs = require ('fs-extra');
 const path = require ('path');