1 files changed, 2 insertions, 0 deletions
diff --git a/lib/_tls_wrap.js b/lib/_tls_wrap.js
index 703f125839..671a5e8520 100644
--- a/lib/_tls_wrap.js
+++ b/lib/_tls_wrap.js
@@ -22,6 +22,8 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+'use strict';
+
 var assert = require('assert');
 var crypto = require('crypto');
 var net = require('net');