diff --git a/lib/node/config.js b/lib/node/config.js
index adf50284..7744bbdb 100644
--- a/lib/node/config.js
+++ b/lib/node/config.js
@@ -556,6 +556,9 @@ Config.prototype.getFile = function getFile(file) {
  */
 
 Config.prototype.ensure = function ensure() {
+  if (fs.unsupported)
+    return Promise.resolve();
+
   return fs.mkdirp(this.prefix);
 };