diff --git a/packages/driver/package.json b/packages/driver/package.json
index 07e0c7e20985..d3566e07a640 100644
--- a/packages/driver/package.json
+++ b/packages/driver/package.json
@@ -63,6 +63,7 @@
     "url-parse": "1.4.7",
     "vanilla-text-mask": "5.1.1",
     "wait-on": "3.2.0",
+    "@cypress/what-is-circular": "1.0.0",
     "zone.js": "0.9.0"
   }
 }
diff --git a/packages/driver/src/cy/commands/navigation.coffee b/packages/driver/src/cy/commands/navigation.coffee
index 3658b8453f89..c300df70e1a8 100644
--- a/packages/driver/src/cy/commands/navigation.coffee
+++ b/packages/driver/src/cy/commands/navigation.coffee
@@ -1,4 +1,5 @@
 _ = require("lodash")
+whatIsCircular = require("@cypress/what-is-circular")
 moment = require("moment")
 UrlParse = require("url-parse")
 Promise = require("bluebird")
@@ -522,6 +523,9 @@ module.exports = (Commands, Cypress, cy, state, config) ->
       if not _.isObject(options.headers)
         $utils.throwErrByPath("visit.invalid_headers")
 
+      if _.isObject(options.body) and path = whatIsCircular(options.body)
+        $utils.throwErrByPath("visit.body_circular", { args: { path }})
+
       if options.log
         message = url
 
diff --git a/packages/driver/src/cy/commands/request.coffee b/packages/driver/src/cy/commands/request.coffee
index ea2db52d7db1..f7e95bfc8cd8 100644
--- a/packages/driver/src/cy/commands/request.coffee
+++ b/packages/driver/src/cy/commands/request.coffee
@@ -1,4 +1,5 @@
 _ = require("lodash")
+whatIsCircular = require("@cypress/what-is-circular")
 Promise = require("bluebird")
 
 $utils = require("../../cypress/utils")
@@ -137,6 +138,9 @@ module.exports = (Commands, Cypress, cy, state, config) ->
       if needsFormSpecified(options)
         options.form = true
 
+      if _.isObject(options.body) and path = whatIsCircular(options.body)
+        $utils.throwErrByPath("request.body_circular", { args: { path }})
+
       ## only set json to true if form isnt true
       ## and we have a valid object for body
       if options.form isnt true and isValidJsonObj(options.body)
diff --git a/packages/driver/src/cypress/error_messages.coffee b/packages/driver/src/cypress/error_messages.coffee
index 16d26dea288c..be3165755d7a 100644
--- a/packages/driver/src/cypress/error_messages.coffee
+++ b/packages/driver/src/cypress/error_messages.coffee
@@ -593,6 +593,11 @@ module.exports = {
     invalid_arguments: "#{cmd('reload')} can only accept a boolean or options as its arguments."
 
   request:
+    body_circular: ({ path }) -> """
+      The `body` parameter supplied to #{cmd('request')} contained a circular reference at the path "#{path.join(".")}".
+
+      `body` can only be a string or an object with no circular references.
+    """
     status_code_flags_invalid: """
     #{cmd('request')} was invoked with { failOnStatusCode: false, retryOnStatusCodeFailure: true }.
 
@@ -931,6 +936,11 @@ module.exports = {
     missing_preset: "#{cmd('viewport')} could not find a preset for: '{{preset}}'. Available presets are: {{presets}}"
 
   visit:
+    body_circular: ({ path }) -> """
+      The `body` parameter supplied to #{cmd('visit')} contained a circular reference at the path "#{path.join(".")}".
+
+      `body` can only be a string or an object with no circular references.
+    """
     status_code_flags_invalid: """
     #{cmd('visit')} was invoked with { failOnStatusCode: false, retryOnStatusCodeFailure: true }.
 
diff --git a/packages/driver/test/cypress/integration/commands/navigation_spec.coffee b/packages/driver/test/cypress/integration/commands/navigation_spec.coffee
index f1c9d0a08048..833b3728114d 100644
--- a/packages/driver/test/cypress/integration/commands/navigation_spec.coffee
+++ b/packages/driver/test/cypress/integration/commands/navigation_spec.coffee
@@ -1455,6 +1455,34 @@ describe "src/cy/commands/navigation", ->
 
         cy.visit("https://google.com/foo")
 
+      it "displays body_circular when body is circular", (done) ->
+        foo = {
+          bar: {
+            baz: {}
+          }
+        }
+
+        foo.bar.baz.quux = foo
+
+        cy.visit({
+          method: "POST"
+          url: "http://foo.invalid/"
+          body: foo
+        })
+
+        cy.on "fail", (err) =>
+          lastLog = @lastLog
+          expect(@logs.length).to.eq(1)
+          expect(lastLog.get("error")).to.eq(err)
+          expect(lastLog.get("state")).to.eq("failed")
+          expect(err.message).to.eq """
+          The `body` parameter supplied to cy.visit() contained a circular reference at the path "bar.baz.quux".
+
+          `body` can only be a string or an object with no circular references.
+          """
+
+          done()
+
   context "#page load", ->
     it "sets initial=true and then removes", ->
       Cookie.remove("__cypress.initial")
diff --git a/packages/driver/test/cypress/integration/commands/request_spec.coffee b/packages/driver/test/cypress/integration/commands/request_spec.coffee
index bcb79f7f51d7..c4aeecfbd029 100644
--- a/packages/driver/test/cypress/integration/commands/request_spec.coffee
+++ b/packages/driver/test/cypress/integration/commands/request_spec.coffee
@@ -751,6 +751,34 @@ describe "src/cy/commands/request", ->
           }
         })
 
+      it "displays body_circular when body is circular", (done) ->
+        foo = {
+          bar: {
+            baz: {}
+          }
+        }
+
+        foo.bar.baz.quux = foo
+
+        cy.request({
+          method: "POST"
+          url: "http://foo.invalid/"
+          body: foo
+        })
+
+        cy.on "fail", (err) =>
+          lastLog = @lastLog
+          expect(@logs.length).to.eq(1)
+          expect(lastLog.get("error")).to.eq(err)
+          expect(lastLog.get("state")).to.eq("failed")
+          expect(err.message).to.eq """
+          The `body` parameter supplied to cy.request() contained a circular reference at the path "bar.baz.quux".
+
+          `body` can only be a string or an object with no circular references.
+          """
+
+          done()
+
       it "does not include redirects when there were no redirects", (done) ->
         backend = Cypress.backend
         .withArgs("http:request")
diff --git a/packages/driver/test/cypress/integration/cypress/cypress_spec.coffee b/packages/driver/test/cypress/integration/cypress/cypress_spec.coffee
index e69ef13af196..183d16971dba 100644
--- a/packages/driver/test/cypress/integration/cypress/cypress_spec.coffee
+++ b/packages/driver/test/cypress/integration/cypress/cypress_spec.coffee
@@ -47,6 +47,20 @@ describe "driver/src/cypress/index", ->
 
         done()
 
+    ## https://github.com/cypress-io/cypress/issues/4346
+    it "can complete if a circular reference is sent", ->
+      foo = {
+        bar: {}
+      }
+
+      foo.bar.baz = foo
+
+      Cypress.backend("foo", foo)
+      .then ->
+        throw new Error("should not reach")
+      .catch (e) ->
+        expect(e.message).to.eq("You requested a backend event we cannot handle: foo")
+
   context ".isCy", ->
     it "returns true on cy, cy chainable", ->
       expect(Cypress.isCy(cy)).to.be.true
@@ -75,4 +89,4 @@ describe "driver/src/cypress/index", ->
       fn = ->
         Cypress.log({ message: 'My Log' })
 
-      expect(fn).to.not.throw()
\ No newline at end of file
+      expect(fn).to.not.throw()
diff --git a/packages/extension/app/background.coffee b/packages/extension/app/background.coffee
index 296bb6972c03..026c8ba1a16d 100644
--- a/packages/extension/app/background.coffee
+++ b/packages/extension/app/background.coffee
@@ -2,6 +2,7 @@ map     = require("lodash/map")
 pick    = require("lodash/pick")
 once    = require("lodash/once")
 Promise = require("bluebird")
+{ client, circularParser } = require("@packages/socket")
 
 HOST = "CHANGE_ME_HOST"
 PATH = "CHANGE_ME_PATH"
@@ -12,19 +13,14 @@ firstOrNull = (cookies) ->
   ## normalize into null when empty array
   cookies[0] ? null
 
-connect = (host, path, io) ->
-  io ?= global.io
-
-  ## bail if io isnt defined
-  return if not io
-
+connect = (host, path) ->
   listenToCookieChanges = once ->
     chrome.cookies.onChanged.addListener (info) ->
       if info.cause isnt "overwrite"
-        client.emit("automation:push:request", "change:cookie", info)
+        ws.emit("automation:push:request", "change:cookie", info)
 
   fail = (id, err) ->
-    client.emit("automation:response", id, {
+    ws.emit("automation:response", id, {
       __error: err.message
       __stack: err.stack
       __name:  err.name
@@ -32,18 +28,20 @@ connect = (host, path, io) ->
 
   invoke = (method, id, args...) ->
     respond = (data) ->
-      client.emit("automation:response", id, {response: data})
+      ws.emit("automation:response", id, {response: data})
 
     Promise.try ->
       automation[method].apply(automation, args.concat(respond))
     .catch (err) ->
       fail(id, err)
 
-  ## cannot use required socket here due
-  ## to bug in socket io client with browserify
-  client = io.connect(host, {path: path, transports: ["websocket"]})
+  ws = client.connect(host, {
+    path: path,
+    transports: ["websocket"]
+    parser: circularParser
+  })
 
-  client.on "automation:request", (id, msg, data) ->
+  ws.on "automation:request", (id, msg, data) ->
     switch msg
       when "get:cookies"
         invoke("getCookies", id, data)
@@ -64,18 +62,18 @@ connect = (host, path, io) ->
       else
         fail(id, {message: "No handler registered for: '#{msg}'"})
 
-  client.on "connect", ->
+  ws.on "connect", ->
     listenToCookieChanges()
 
-    client.emit("automation:client:connected")
+    ws.emit("automation:client:connected")
 
-  return client
+  return ws
 
 ## initially connect
-connect(HOST, PATH, global.io)
+connect(HOST, PATH)
 
 automation = {
-  connect: connect
+  connect
 
   getUrl: (cookie = {}) ->
     prefix = if cookie.secure then "https://" else "http://"
diff --git a/packages/extension/app/manifest.json b/packages/extension/app/manifest.json
index 4248dddbc603..98c2a503dd2e 100644
--- a/packages/extension/app/manifest.json
+++ b/packages/extension/app/manifest.json
@@ -24,7 +24,6 @@
   },
   "background": {
     "scripts": [
-      "socket.io.js",
       "background.js"
     ]
   },
diff --git a/packages/extension/gulpfile.coffee b/packages/extension/gulpfile.coffee
index d417e11841c2..91fd9b08ad99 100644
--- a/packages/extension/gulpfile.coffee
+++ b/packages/extension/gulpfile.coffee
@@ -9,11 +9,6 @@ Promise    = require("bluebird")
 coffeeify  = require("coffeeify")
 browserify = require("browserify")
 icons      = require("@cypress/icons")
-ext        = require("./")
-
-gulp.task "copy:socket:client", ->
-  gulp.src(require("../socket").getPathToClientSource())
-  .pipe(gulp.dest("dist"))
 
 gulp.task "clean", ->
   gulp.src("dist")
@@ -71,7 +66,6 @@ gulp.task "watch", ["build"], ->
 
 gulp.task "build", ->
   runSeq "clean", [
-    "copy:socket:client"
     "icons"
     "logos"
     "manifest"
diff --git a/packages/extension/test/integration/background_spec.coffee b/packages/extension/test/integration/background_spec.coffee
index c7f4d3c44444..0a43b0ea25b2 100644
--- a/packages/extension/test/integration/background_spec.coffee
+++ b/packages/extension/test/integration/background_spec.coffee
@@ -94,10 +94,6 @@ tab3 = {
 }
 
 describe "app/background", ->
-  before ->
-    @io = global.io
-    global.io = socket.client
-
   beforeEach (done) ->
     @httpSrv = http.createServer()
     @server  = socket.server(@httpSrv, {path: "/__socket.io"})
@@ -107,9 +103,6 @@ describe "app/background", ->
     @server.close()
     @httpSrv.close -> done()
 
-  after ->
-    global.io = @io
-
   context ".connect", ->
     it "can connect", (done) ->
       @server.on "connection", -> done()
diff --git a/packages/extension/test/spec_helper.coffee b/packages/extension/test/spec_helper.coffee
index 5a4a28bde0dd..7be29a687d06 100644
--- a/packages/extension/test/spec_helper.coffee
+++ b/packages/extension/test/spec_helper.coffee
@@ -5,13 +5,9 @@ sinonChai = require("sinon-chai")
 chai.use(sinonChai)
 
 global.expect = chai.expect
-global.io = {
-  connect: ->
-    return {on: ->}
-}
 
 beforeEach ->
   @sandbox = sinon.sandbox.create()
 
 afterEach ->
-  @sandbox.restore()
\ No newline at end of file
+  @sandbox.restore()
diff --git a/packages/network/test/support/servers.ts b/packages/network/test/support/servers.ts
index de12fdba407d..340cdc607c00 100644
--- a/packages/network/test/support/servers.ts
+++ b/packages/network/test/support/servers.ts
@@ -14,13 +14,16 @@ export interface AsyncServer {
 function addDestroy(server: http.Server | https.Server) {
   let connections = []
 
-  server.on('connection', function(conn) {
+  function trackConn(conn) {
     connections.push(conn)
 
     conn.on('close', () => {
       connections = connections.filter(connection => connection !== conn)
     })
-  })
+  }
+
+  server.on('connection', trackConn)
+  server.on('secureConnection', trackConn)
 
   // @ts-ignore Property 'destroy' does not exist on type 'Server'.
   server.destroy = function(cb) {
diff --git a/packages/network/test/unit/agent_spec.ts b/packages/network/test/unit/agent_spec.ts
index 687c53d1f398..99dd08cf92e5 100644
--- a/packages/network/test/unit/agent_spec.ts
+++ b/packages/network/test/unit/agent_spec.ts
@@ -1,6 +1,5 @@
 import Bluebird from 'bluebird'
 import chai from 'chai'
-import { EventEmitter } from 'events'
 import http from 'http'
 import https from 'https'
 import net from 'net'
@@ -175,7 +174,8 @@ describe('lib/agent', function() {
           return new Bluebird((resolve) => {
             Io.client(`http://localhost:${HTTP_PORT}`, {
               agent: this.agent,
-              transports: ['websocket']
+              transports: ['websocket'],
+              rejectUnauthorized: false
             }).on('message', resolve)
           })
           .then(msg => {
@@ -191,7 +191,8 @@ describe('lib/agent', function() {
           return new Bluebird((resolve) => {
             Io.client(`https://localhost:${HTTPS_PORT}`, {
               agent: this.agent,
-              transports: ['websocket']
+              transports: ['websocket'],
+              rejectUnauthorized: false
             }).on('message', resolve)
           })
           .then(msg => {
@@ -357,7 +358,8 @@ describe('lib/agent', function() {
           Io.client(`${testCase.protocol}://foo.bar.baz.invalid`, {
             agent: <any>testCase.agent,
             transports: ['websocket'],
-            timeout: 1
+            timeout: 1,
+            rejectUnauthorized: false
           })
           .on('message', reject)
           .on('connect_error', resolve)
diff --git a/packages/runner/lib/test-setup.js b/packages/runner/lib/test-setup.js
index b47aa416a4cf..c13891df3f64 100644
--- a/packages/runner/lib/test-setup.js
+++ b/packages/runner/lib/test-setup.js
@@ -2,7 +2,7 @@ const chai = require('chai')
 const JSDOM = require('jsdom').JSDOM
 const sinonChai = require('sinon-chai')
 const $Cypress = require('@packages/driver')
-const io = require('@packages/socket')
+const { client } = require('@packages/socket')
 
 // http://airbnb.io/enzyme/docs/guides/jsdom.html
 const jsdom = new JSDOM('<!doctype html><html><body></body></html>')
@@ -52,6 +52,6 @@ class Runner {
 
 global.Mocha = { Runnable, Runner }
 $Cypress.create = () => {}
-io.connect = () => {
+client.connect = () => {
   return { emit: () => {}, on: () => {} }
 }
diff --git a/packages/runner/src/lib/event-manager.js b/packages/runner/src/lib/event-manager.js
index d449e67c037b..796094697a8d 100644
--- a/packages/runner/src/lib/event-manager.js
+++ b/packages/runner/src/lib/event-manager.js
@@ -2,20 +2,21 @@ import _ from 'lodash'
 import { EventEmitter } from 'events'
 import Promise from 'bluebird'
 import { action } from 'mobx'
-import io from '@packages/socket'
+import { client, circularParser } from '@packages/socket'
 
 import automation from './automation'
 import logger from './logger'
 
 import $Cypress, { $ } from '@packages/driver'
 
-const channel = io.connect({
+const ws = client.connect({
   path: '/__socket.io',
   transports: ['websocket'],
+  parser: circularParser,
 })
 
-channel.on('connect', () => {
-  channel.emit('runner:connected')
+ws.on('connect', () => {
+  ws.emit('runner:connected')
 })
 
 const driverToReporterEvents = 'paused'.split(' ')
@@ -42,18 +43,18 @@ const eventManager = {
       return this._reRun(state)
     }
 
-    channel.emit('is:automation:client:connected', connectionInfo, action('automationEnsured', (isConnected) => {
+    ws.emit('is:automation:client:connected', connectionInfo, action('automationEnsured', (isConnected) => {
       state.automation = isConnected ? automation.CONNECTED : automation.MISSING
-      channel.on('automation:disconnected', action('automationDisconnected', () => {
+      ws.on('automation:disconnected', action('automationDisconnected', () => {
         state.automation = automation.DISCONNECTED
       }))
     }))
 
-    channel.on('change:to:url', (url) => {
+    ws.on('change:to:url', (url) => {
       window.location.href = url
     })
 
-    channel.on('automation:push:message', (msg, data = {}) => {
+    ws.on('automation:push:message', (msg, data = {}) => {
       if (!Cypress) return
 
       switch (msg) {
@@ -66,7 +67,7 @@ const eventManager = {
     })
 
     _.each(socketRerunEvents, (event) => {
-      channel.on(event, rerun)
+      ws.on(event, rerun)
     })
 
     reporterBus.on('runner:console:error', (testId) => {
@@ -140,7 +141,7 @@ const eventManager = {
     })
 
     reporterBus.on('external:open', (url) => {
-      channel.emit('external:open', url)
+      ws.emit('external:open', url)
     })
 
     const $window = $(window)
@@ -170,7 +171,7 @@ const eventManager = {
 
   start (config) {
     if (config.socketId) {
-      channel.emit('app:connect', config.socketId)
+      ws.emit('app:connect', config.socketId)
     }
   },
 
@@ -182,7 +183,7 @@ const eventManager = {
 
     this._addListeners()
 
-    channel.emit('watch:test:file', specPath)
+    ws.emit('watch:test:file', specPath)
   },
 
   initialize ($autIframe, config) {
@@ -190,7 +191,7 @@ const eventManager = {
 
     // get the current runnable in case we reran mid-test due to a visit
     // to a new domain
-    channel.emit('get:existing:run:state', (state = {}) => {
+    ws.emit('get:existing:run:state', (state = {}) => {
       const runnables = Cypress.normalizeAll(state.tests)
       const run = () => {
         this._runDriver(state)
@@ -214,7 +215,7 @@ const eventManager = {
       }
 
       if (config.isTextTerminal && !state.currentId) {
-        channel.emit('set:runnables', runnables, run)
+        ws.emit('set:runnables', runnables, run)
       } else {
         run()
       }
@@ -223,12 +224,12 @@ const eventManager = {
 
   _addListeners () {
     Cypress.on('message', (msg, data, cb) => {
-      channel.emit('client:request', msg, data, cb)
+      ws.emit('client:request', msg, data, cb)
     })
 
     _.each(driverToSocketEvents, (event) => {
       Cypress.on(event, (...args) => {
-        return channel.emit(event, ...args)
+        return ws.emit(event, ...args)
       })
     })
 
@@ -315,7 +316,7 @@ const eventManager = {
 
   stop () {
     localBus.removeAllListeners()
-    channel.off()
+    ws.off()
   },
 
   _reRun (state) {
@@ -355,11 +356,11 @@ const eventManager = {
   },
 
   notifyRunningSpec (specFile) {
-    channel.emit('spec:changed', specFile)
+    ws.emit('spec:changed', specFile)
   },
 
   focusTests () {
-    channel.emit('focus:tests')
+    ws.emit('focus:tests')
   },
 
   snapshotUnpinned () {
@@ -377,7 +378,7 @@ const eventManager = {
   },
 
   launchBrowser (browser) {
-    channel.emit('reload:browser', window.location.toString(), browser && browser.name)
+    ws.emit('reload:browser', window.location.toString(), browser && browser.name)
   },
 
   // clear all the cypress specific cookies
@@ -396,7 +397,7 @@ const eventManager = {
   },
 
   saveState (state) {
-    channel.emit('save:app:state', state)
+    ws.emit('save:app:state', state)
   },
 }
 
diff --git a/packages/server/lib/socket.coffee b/packages/server/lib/socket.coffee
index ee662ade0b78..af47a7df876d 100644
--- a/packages/server/lib/socket.coffee
+++ b/packages/server/lib/socket.coffee
@@ -124,6 +124,7 @@ class Socket
       destroyUpgrade: false
       serveClient: false
       cookie: cookie
+      parser: socketIo.circularParser
     })
 
   startListening: (server, automation, config, options) ->
diff --git a/packages/server/test/integration/websockets_spec.coffee b/packages/server/test/integration/websockets_spec.coffee
index 7668c5df4dcf..a818f5983001 100644
--- a/packages/server/test/integration/websockets_spec.coffee
+++ b/packages/server/test/integration/websockets_spec.coffee
@@ -175,6 +175,7 @@ describe "Web Sockets", ->
         @wsClient = socketIo.client(@cfg.proxyUrl, {
           path: @cfg.socketIoRoute
           transports: ["websocket"]
+          parser: socketIo.circularParser
         })
         @wsClient.on "connect", -> done()
 
@@ -197,6 +198,7 @@ describe "Web Sockets", ->
           agent: agent
           path: @cfg.socketIoRoute
           transports: ["websocket"]
+          parser: socketIo.circularParser
         })
         @wsClient.on "connect", -> done()
 
@@ -220,6 +222,8 @@ describe "Web Sockets", ->
         @wsClient = socketIo.client("https://localhost:#{wssPort}", {
           agent: agent
           path: @cfg.socketIoRoute
+          parser: socketIo.circularParser
+          rejectUnauthorized: false
         })
         @wsClient.on "connect", -> done()
 
diff --git a/packages/server/test/unit/socket_spec.coffee b/packages/server/test/unit/socket_spec.coffee
index cc07d6f713d6..fd1ebfebae83 100644
--- a/packages/server/test/unit/socket_spec.coffee
+++ b/packages/server/test/unit/socket_spec.coffee
@@ -64,12 +64,29 @@ describe "lib/socket", ->
           agent: agent
           path: socketIoRoute
           transports: ["websocket"]
+          parser: socketIo.circularParser
         })
       return
 
     afterEach ->
       @client.disconnect()
 
+    ## https://github.com/cypress-io/cypress/issues/4346
+    it "can emit a circular object without crashing", (done) ->
+      foo = {
+        bar: {}
+      }
+
+      foo.bar.baz = foo
+
+      ## going to stub exec here just so we have something that we can
+      ## control the resolved value of
+      sinon.stub(exec, 'run').resolves(foo)
+
+      @client.emit "backend:request", "exec", "quuz", (res) ->
+        expect(res.response).to.deep.eq(foo)
+        done()
+
     context "on(automation:request)", ->
       describe "#onAutomation", ->
         before ->
diff --git a/packages/socket/index.js b/packages/socket/index.js
index 77ca6ef899ed..c482fe1cee9d 100644
--- a/packages/socket/index.js
+++ b/packages/socket/index.js
@@ -1 +1 @@
-module.exports = require("./lib/socket")
\ No newline at end of file
+module.exports = require('./lib/socket')
diff --git a/packages/socket/lib/browser.js b/packages/socket/lib/browser.js
new file mode 100644
index 000000000000..36c1f83138bd
--- /dev/null
+++ b/packages/socket/lib/browser.js
@@ -0,0 +1,8 @@
+const client = require('socket.io-client')
+const circularParser = require('socket.io-circular-parser')
+
+module.exports = {
+  client,
+
+  circularParser,
+}
diff --git a/packages/socket/lib/client.js b/packages/socket/lib/client.js
deleted file mode 100644
index e13ac9d1b45d..000000000000
--- a/packages/socket/lib/client.js
+++ /dev/null
@@ -1 +0,0 @@
-module.exports = require('socket.io-client')
diff --git a/packages/socket/lib/socket.js b/packages/socket/lib/socket.js
index 7eff210b2d72..3b90991616fe 100644
--- a/packages/socket/lib/socket.js
+++ b/packages/socket/lib/socket.js
@@ -1,15 +1,18 @@
 const fs = require('fs')
 const path = require('path')
 const server = require('socket.io')
-const version = require('socket.io-client/package.json').version
+const { version } = require('socket.io-client/package.json')
+const { client, circularParser } = require('./browser')
+
 const clientPath = require.resolve('socket.io-client')
-const client = require('./client')
 
 module.exports = {
   server,
 
   client,
 
+  circularParser,
+
   getPathToClientSource () {
     // clientPath returns the path to socket.io-client/lib/index.js
     // so walk up two levels to get to the root
diff --git a/packages/socket/package.json b/packages/socket/package.json
index a74615514b86..f45473ff91f0 100644
--- a/packages/socket/package.json
+++ b/packages/socket/package.json
@@ -3,8 +3,9 @@
   "version": "0.0.0",
   "private": true,
   "main": "index.js",
-  "browser": "./lib/client.js",
+  "browser": "./lib/browser.js",
   "scripts": {
+    "postinstall": "patch-package",
     "pretest": "npm run check-deps-pre",
     "test": "cross-env NODE_ENV=test bin-up mocha --reporter mocha-multi-reporters --reporter-options configFile=../../mocha-reporter-config.json",
     "pretest-watch": "npm run check-deps-pre",
@@ -17,12 +18,14 @@
     "lib"
   ],
   "dependencies": {
-    "socket.io": "1.7.4",
-    "socket.io-client": "1.7.4"
+    "socket.io": "2.2.0",
+    "socket.io-circular-parser": "cypress-io/socket.io-circular-parser#c5a895a0fef6d19d457a38a515dbb5c18feeb591",
+    "socket.io-client": "2.2.0"
   },
   "devDependencies": {
     "bin-up": "1.2.0",
     "chai": "3.5.0",
-    "cross-env": "5.2.0"
+    "cross-env": "5.2.0",
+    "patch-package": "6.1.2"
   }
 }
diff --git a/packages/socket/patches/has-binary2+1.0.3.patch b/packages/socket/patches/has-binary2+1.0.3.patch
new file mode 100644
index 000000000000..1da07225c972
--- /dev/null
+++ b/packages/socket/patches/has-binary2+1.0.3.patch
@@ -0,0 +1,94 @@
+diff --git a/node_modules/has-binary2/index.js b/node_modules/has-binary2/index.js
+index cf756a3..277ed03 100644
+--- a/node_modules/has-binary2/index.js
++++ b/node_modules/has-binary2/index.js
+@@ -4,19 +4,19 @@
+  * Module requirements.
+  */
+ 
+-var isArray = require('isarray');
++let isArray = require('isarray')
+ 
+-var toString = Object.prototype.toString;
+-var withNativeBlob = typeof Blob === 'function' ||
+-                        typeof Blob !== 'undefined' && toString.call(Blob) === '[object BlobConstructor]';
+-var withNativeFile = typeof File === 'function' ||
+-                        typeof File !== 'undefined' && toString.call(File) === '[object FileConstructor]';
++let toString = Object.prototype.toString
++let withNativeBlob = typeof global.Blob === 'function' || toString.call(global.Blob) === '[object BlobConstructor]'
++let withNativeFile = typeof global.File === 'function' || toString.call(global.File) === '[object FileConstructor]'
+ 
+ /**
+  * Module exports.
+  */
+ 
+-module.exports = hasBinary;
++module.exports = function hasBinaryCircular (obj) {
++  return hasBinary(obj, [])
++}
+ 
+ /**
+  * Checks for binary data.
+@@ -27,38 +27,45 @@ module.exports = hasBinary;
+  * @api public
+  */
+ 
+-function hasBinary (obj) {
++function hasBinary (obj, known) {
+   if (!obj || typeof obj !== 'object') {
+-    return false;
++    return false
++  }
++
++  if (known.indexOf(obj) >= 0) {
++    return false
+   }
+ 
++  known.push(obj)
++
+   if (isArray(obj)) {
+-    for (var i = 0, l = obj.length; i < l; i++) {
+-      if (hasBinary(obj[i])) {
+-        return true;
++    for (let i = 0, l = obj.length; i < l; i++) {
++      if (hasBinary(obj[i], known)) {
++        return true
+       }
+     }
+-    return false;
++
++    return false
+   }
+ 
+-  if ((typeof Buffer === 'function' && Buffer.isBuffer && Buffer.isBuffer(obj)) ||
+-    (typeof ArrayBuffer === 'function' && obj instanceof ArrayBuffer) ||
+-    (withNativeBlob && obj instanceof Blob) ||
+-    (withNativeFile && obj instanceof File)
++  if ((typeof global.Buffer === 'function' && global.Buffer.isBuffer && global.Buffer.isBuffer(obj)) ||
++     (typeof global.ArrayBuffer === 'function' && obj instanceof ArrayBuffer) ||
++     (withNativeBlob && obj instanceof Blob) ||
++     (withNativeFile && obj instanceof File)
+   ) {
+-    return true;
++    return true
+   }
+ 
+   // see: https://github.com/Automattic/has-binary/pull/4
+-  if (obj.toJSON && typeof obj.toJSON === 'function' && arguments.length === 1) {
+-    return hasBinary(obj.toJSON(), true);
++  if (obj.toJSON && typeof obj.toJSON === 'function') {
++    return hasBinary(obj.toJSON(), known)
+   }
+ 
+-  for (var key in obj) {
+-    if (Object.prototype.hasOwnProperty.call(obj, key) && hasBinary(obj[key])) {
+-      return true;
++  for (let key in obj) {
++    if (Object.prototype.hasOwnProperty.call(obj, key) && hasBinary(obj[key], known)) {
++      return true
+     }
+   }
+ 
+-  return false;
++  return false
+ }