diff --git a/examples/multi-router/index.js b/examples/multi-router/index.js
index 1c057352da..5a45103e5e 100644
--- a/examples/multi-router/index.js
+++ b/examples/multi-router/index.js
@@ -3,9 +3,10 @@
 var express = require('../..');
 
 var app = module.exports = express();
-
-app.use('/api/v1', require('./controllers/api_v1'));
-app.use('/api/v2', require('./controllers/api_v2'));
+const api_v1 = require('./controllers/api_v1');
+const api_v2 = require('./controllers/api_v2');
+app.use('/api/v1', api_v1.handle.bind(api_v1));
+app.use('/api/v2', api_v2.handle.bind(api_v2));
 
 app.get('/', function(req, res) {
   res.send('Hello from root route.')
diff --git a/lib/router.js b/lib/router.js
index 2b929f6f67..94fb96b22d 100644
--- a/lib/router.js
+++ b/lib/router.js
@@ -17,7 +17,6 @@ var methods = require('methods')
 var mixin = require('utils-merge')
 var parseUrl = require('parseurl')
 var Route = require('./route')
-var setPrototypeOf = require('setprototypeof')
 
 /**
  * Module variables.
@@ -52,21 +51,13 @@ function Router (options) {
   }
 
   var opts = options || {}
+  this.caseSensitive = opts.caseSensitive
+  this.mergeParams = opts.mergeParams
+  this.params = {}
+  this.strict = opts.strict
+  this.stack = []
 
-  function router (req, res, next) {
-    router.handle(req, res, next)
-  }
-
-  // inherit from the correct prototype
-  setPrototypeOf(router, this)
-
-  router.caseSensitive = opts.caseSensitive
-  router.mergeParams = opts.mergeParams
-  router.params = {}
-  router.strict = opts.strict
-  router.stack = []
-
-  return router
+  return this
 }
 
 /**
diff --git a/package-lock.json b/package-lock.json
index c31259f753..f16efc5efc 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@hubot-friends/express",
-  "version": "5.0.0",
+  "version": "0.0.0-development",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@hubot-friends/express",
-      "version": "5.0.0",
+      "version": "0.0.0-development",
       "license": "MIT",
       "dependencies": {
         "accepts": "^1.3.8",
diff --git a/test/AppOptions.mjs b/test/AppOptions.mjs
index ae22428a7d..ce0ea798d8 100644
--- a/test/AppOptions.mjs
+++ b/test/AppOptions.mjs
@@ -69,7 +69,7 @@ describe('OPTIONS', () => {
     const router = new express.Router()
 
     router.get('/users', (req, res) => {})
-    app.use(router)
+    app.use(router.handle.bind(router))
     app.get('/other', (req, res) => {})
 
     request(server)
@@ -90,7 +90,7 @@ describe('OPTIONS', () => {
         res.writeHead(200)
         next()
       })
-      app.use(router)
+      app.use(router.handle.bind(router))
       app.use((err, req, res, next) => {
         res.end('true')
       })
diff --git a/test/AppRouter.mjs b/test/AppRouter.mjs
index d7bb12c1b2..a28ea8aa1a 100644
--- a/test/AppRouter.mjs
+++ b/test/AppRouter.mjs
@@ -29,7 +29,7 @@ describe('app.router', () => {
       next()
     })
 
-    app.get('/user/:id', handler1, router, handler2)
+    app.get('/user/:id', handler1, router.handle.bind(router), handler2)
 
     request(server)
     .get('/user/1')
@@ -275,7 +275,7 @@ describe('app.router', () => {
         res.send(req.params)
       })
 
-      app.use('/user/:user', router)
+      app.use('/user/:user', router.handle.bind(router))
 
       request(app)
       .get('/user/1/get')
@@ -291,7 +291,7 @@ describe('app.router', () => {
         res.send(keys.map(k => [k, req.params[k]]))
       })
 
-      app.use('/user/:user', router)
+      app.use('/user/:user', router.handle.bind(router))
 
       request(app)
       .get('/user/tj/get')
@@ -307,7 +307,7 @@ describe('app.router', () => {
         res.send(keys.map(k => [k, req.params[k]] ))
       })
 
-      app.use('/user/:thing', router)
+      app.use('/user/:thing', router.handle.bind(router))
 
       request(app)
       .get('/user/tj/get')
@@ -323,7 +323,7 @@ describe('app.router', () => {
         res.send(keys.map(k => [k, req.params[k]] ))
       })
 
-      app.use('/user/id-(\\d+)', router)
+      app.use('/user/id-(\\d+)', router.handle.bind(router))
 
       request(app)
       .get('/user/id-10/profile.json')
@@ -339,7 +339,7 @@ describe('app.router', () => {
         res.send(keys.map(k => [k, req.params[k]] ))
       })
 
-      app.use('/user/id-(\\d+)/name-(\\w+)', router)
+      app.use('/user/id-(\\d+)/name-(\\w+)', router.handle.bind(router))
 
       request(app)
       .get('/user/id-10/name-tj/profile')
@@ -355,7 +355,7 @@ describe('app.router', () => {
         res.send(keys.map(k => [k, req.params[k]] ))
       })
 
-      app.use('/user/id-(\\d+)', router)
+      app.use('/user/id-(\\d+)', router.handle.bind(router))
 
       request(app)
       .get('/user/id-10/name-tj')
@@ -373,7 +373,7 @@ describe('app.router', () => {
 
       app.use('/user/', (req, res, next) => {
         req.params = 3; // wat?
-        router(req, res, next)
+        router.handle(req, res, next)
       })
 
       request(app)
@@ -870,7 +870,7 @@ describe('app.router', () => {
         res.end('failure')
       })
 
-      app.use(router)
+      app.use(router.handle.bind(router))
 
       app.get('/foo', (req, res) => {
         res.end('success')
@@ -958,7 +958,7 @@ describe('app.router', () => {
         res.send('saw ' + err.name + ': ' + err.message)
       })
 
-      app.use(router)
+      app.use(router.handle.bind(router))
 
       request(app)
       .get('/')
@@ -977,7 +977,7 @@ describe('app.router', () => {
         res.send('saw ' + err.name + ': ' + err.message)
       })
 
-      app.use(router)
+      app.use(router.handle.bind(router))
 
       request(app)
       .get('/')
@@ -997,7 +997,7 @@ describe('app.router', () => {
         done(new Error('Unexpected middleware invoke'))
       })
 
-      app.use(router)
+      app.use(router.handle.bind(router))
 
       request(app)
       .get('/foo')
@@ -1021,7 +1021,7 @@ describe('app.router', () => {
           res.send('saw ' + err.name + ': ' + err.message)
         })
 
-        app.use(router)
+        app.use(router.handle.bind(router))
 
         request(app)
         .get('/')
@@ -1044,7 +1044,7 @@ describe('app.router', () => {
           res.send('saw ' + err.name + ': ' + err.message)
         })
 
-        app.use(router)
+        app.use(router.handle.bind(router))
 
         request(app)
         .get('/')
@@ -1068,7 +1068,7 @@ describe('app.router', () => {
           done(new Error('Unexpected middleware invoke'))
         })
 
-        app.use(router)
+        app.use(router.handle.bind(router))
 
         request(app)
         .get('/foo')
diff --git a/test/ReqBaseUrl.mjs b/test/ReqBaseUrl.mjs
index 4291585eb7..46bbf98b09 100644
--- a/test/ReqBaseUrl.mjs
+++ b/test/ReqBaseUrl.mjs
@@ -25,7 +25,7 @@ describe('req', () => {
       sub.get('/:b', (req, res) => {
         res.end(req.baseUrl)
       })
-      app.use('/:a', sub)
+      app.use('/:a', sub.handle.bind(sub))
 
       request(app)
       .get('/foo/bar')
@@ -41,9 +41,9 @@ describe('req', () => {
       sub3.get('/:d', (req, res) => {
         res.end(req.baseUrl)
       })
-      sub2.use('/:c', sub3)
-      sub1.use('/:b', sub2)
-      app.use('/:a', sub1)
+      sub2.use('/:c', sub3.handle.bind(sub3))
+      sub1.use('/:b', sub2.handle.bind(sub2))
+      app.use('/:a', sub1.handle.bind(sub1))
 
       request(app)
       .get('/foo/bar/baz/zed')
@@ -61,12 +61,12 @@ describe('req', () => {
         urls.push('0@' + req.baseUrl)
         next()
       })
-      sub2.use('/:c', sub3)
+      sub2.use('/:c', sub3.handle.bind(sub3))
       sub1.use('/', (req, res, next) => {
         urls.push('1@' + req.baseUrl)
         next()
       })
-      sub1.use('/bar', sub2)
+      sub1.use('/bar', sub2.handle.bind(sub2))
       sub1.use('/bar', (req, res, next) => {
         urls.push('2@' + req.baseUrl)
         next()
@@ -75,7 +75,7 @@ describe('req', () => {
         urls.push('3@' + req.baseUrl)
         next()
       })
-      app.use('/:a', sub1)
+      app.use('/:a', sub1.handle.bind(sub1))
       app.use((req, res, next) => {
         urls.push('4@' + req.baseUrl)
         res.end(urls.join(','))
diff --git a/test/ResFormat.mjs b/test/ResFormat.mjs
index 217ba90313..61df142c74 100644
--- a/test/ResFormat.mjs
+++ b/test/ResFormat.mjs
@@ -146,7 +146,7 @@ describe('res', () => {
         res.send('Supports: ' + err.types.join(', '))
       })
 
-      app.use(router)
+      app.use(router.handle.bind(router))
 
       test(app)
     })
diff --git a/test/Router.mjs b/test/Router.mjs
index 0cc9450def..6bf92381cc 100644
--- a/test/Router.mjs
+++ b/test/Router.mjs
@@ -8,7 +8,7 @@ import { describe, it } from 'node:test'
 describe('Router', () => {
   it('should return a function with router methods', () =>  {
     const router = new Router()
-    assert(typeof router === 'function')
+    assert(router instanceof Router)
 
     assert(typeof router.get === 'function')
     assert(typeof router.handle === 'function')
@@ -22,7 +22,7 @@ describe('Router', () => {
     another.get('/bar', (req, res) => {
       res.end()
     })
-    router.use('/foo', another)
+    router.use('/foo', another.handle.bind(another))
 
     router.handle({ url: '/foo/bar', method: 'GET' }, { end: done}, done)
   })
@@ -35,7 +35,7 @@ describe('Router', () => {
       assert.strictEqual(req.params.bar, 'route')
       res.end()
     })
-    router.use('/:foo', another)
+    router.use('/:foo', another.handle.bind(another))
 
     router.handle({ url: '/test/route', method: 'GET' }, { end: done}, done)
   })
@@ -472,9 +472,9 @@ describe('Router', () => {
         req.user = user
         next()
       })
-
-      router.use('/foo/:user/', new Router())
-      router.use('/foo/:user/', sub)
+      const r = new Router()
+      router.use('/foo/:user/', r.handle.bind(r))
+      router.use('/foo/:user/', sub.handle.bind(sub))
 
       router.handle(req, {}, err => {
         if (err) return done(err)
@@ -499,9 +499,9 @@ describe('Router', () => {
         req.user = user
         next()
       })
-
-      router.use('/foo/:user/', new Router())
-      router.use('/:user/bob/', sub)
+      const r = new Router()
+      router.use('/foo/:user/', r.handle.bind(r))
+      router.use('/:user/bob/', sub.handle.bind(sub))
 
       router.handle(req, {}, err => {
         if (err) return done(err)
@@ -530,9 +530,9 @@ describe('Router', () => {
         req.ms = ms
         setTimeout(next, ms)
       })
-
-      router.use('/foo/:ms/', new Router())
-      router.use('/foo/:ms/', sub)
+      const r = new Router()
+      router.use('/foo/:ms/', r.handle.bind(r))
+      router.use('/foo/:ms/', sub.handle.bind(sub))
 
       router.handle(req1, {}, function(err) {
         assert.ifError(err)