diff --git a/lib/markdownlint.js b/lib/markdownlint.js
index 68c75ddf..611a7ccb 100644
--- a/lib/markdownlint.js
+++ b/lib/markdownlint.js
@@ -12,8 +12,13 @@ const cache = require("./cache");
 
 const deprecatedRuleNames = [ "MD002" ];
 
+function bork() {}
+
 // Validates the list of rules for structure and reuse
 function validateRuleList(ruleList) {
+  if (ruleList.length > 100) {
+    bork();
+  }
   let result = null;
   if (ruleList.length === rules.length) {
     // No need to validate if only using built-in rules