diff --git a/.gitignore b/.gitignore
index 7d33200..2e047d1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -34,3 +34,6 @@ node_modules
 
 # Optional REPL history
 .node_repl_history
+
+# npm v5+ lockfile
+package-lock.json