diff --git a/lib/local-web-server.js b/lib/local-web-server.js
index 4f8c23c..d9f21fd 100644
--- a/lib/local-web-server.js
+++ b/lib/local-web-server.js
@@ -246,7 +246,6 @@ function loadModule (modulePath) {
   return module
 }
 
-
 function getIPList () {
   const flatten = require('reduce-flatten')
   const os = require('os')
diff --git a/lib/middleware.js b/lib/middleware.js
new file mode 100644
index 0000000..6b654b7
--- /dev/null
+++ b/lib/middleware.js
@@ -0,0 +1,14 @@
+'use strict'
+
+class Middleware {
+  /**
+   * Return one or more options definitions to collect command-line input
+   * @returns {OptionDefinition|OptionDefinition[]}
+   */
+  optionDefinitions () {}
+
+  /**
+   * Return one of more middleware functions with three args (req, res and next). Can be created by express, Koa or hand-rolled.
+   */
+   middleware (localWebServer) {}
+}