diff --git a/src/index.js b/src/index.js
index a4fc1d5..4f88c35 100644
--- a/src/index.js
+++ b/src/index.js
@@ -26,7 +26,7 @@ let defaultCheckers = {
 
 function reachedRoot(candidatePath) {
 	/* Returns true if we hit the root of the filesystem; like / or C:\ */
-	return /^(?:\/|a-z:\\)$/i.test(candidatePath);
+	return /^(?:\/|[a-z]:\\)$/i.test(candidatePath);
 }
 
 module.exports = function(options) {