diff --git a/package.json b/package.json
index c785e9a..e253543 100644
--- a/package.json
+++ b/package.json
@@ -60,7 +60,6 @@
     "babylon": "6.14.1",
     "convert-source-map": "1.3.0",
     "escape-string-regexp": "1.0.5",
-    "object.entries": "1.0.4",
     "source-map": "0.5.6",
     "string-hash": "1.1.1",
     "stylis": "1.2.3"
diff --git a/src/render.js b/src/render.js
index 10bc8ae..09d00d9 100644
--- a/src/render.js
+++ b/src/render.js
@@ -1,48 +1,40 @@
-import entries from 'object.entries'
-
-const {hasOwnProperty} = Object.prototype
-const tags = {}
-let prevStyles = {}
+const tags = new Map()
+let prevStyles = new Map()
 
 export default typeof window === 'undefined' ? renderOnServer : renderOnClient
 
 function renderOnServer() {}
 
-function renderOnClient(components) {
-  const styles = {}
-  for (const c of components) {
-    styles[c.props.styleId] = c
-  }
-
+function renderOnClient(styles) {
   patch(diff(prevStyles, styles))
-
   prevStyles = styles
 }
 
 function diff(a, b) {
-  const added = entries(b).filter(([k]) => !hasOwnProperty.call(a, k))
-  const removed = entries(a).filter(([k]) => !hasOwnProperty.call(b, k))
+  const added = Array.from(b.entries()).filter(([k]) => !a.has(k))
+  const removed = Array.from(a.entries()).filter(([k]) => !b.has(k))
   return [added, removed]
 }
 
-const fromServer = {}
+const fromServer = new Map()
 
 function patch([added, removed]) {
   for (const [id, c] of added) {
     // avoid duplicates from server-rendered markup
-    if (undefined === fromServer[id]) {
-      fromServer[id] = document.getElementById(`__jsx-style-${id}`)
+    if (!fromServer.has(id)) {
+      fromServer.set(id, document.getElementById(`__jsx-style-${id}`))
     }
 
-    tags[id] = fromServer[id] || makeStyleTag(c.props.css)
+    const tag = fromServer.get(id) || makeStyleTag(c.props.css)
+    tags.set(id, tag)
   }
 
   for (const [id] of removed) {
-    const t = tags[id]
-    delete tags[id]
+    const t = tags.get(id)
+    tags.delete(id)
     t.parentNode.removeChild(t)
     // avoid checking the DOM later on
-    fromServer[id] = null
+    fromServer.delete(id)
   }
 }
 
diff --git a/src/server.js b/src/server.js
index 25e5dd2..12b1286 100644
--- a/src/server.js
+++ b/src/server.js
@@ -1,22 +1,18 @@
 import React from 'react'
 import {flush} from './style'
 
-const {hasOwnProperty} = Object.prototype
-
 export default function flushToReact() {
   const mem = flush()
   const arr = []
-  for (const id in mem) {
-    if (hasOwnProperty.call(mem, id)) {
-      arr.push(React.createElement('style', {
-        id: `__jsx-style-${id}`,
-        // avoid warnings upon render with a key
-        key: `__jsx-style-${id}`,
-        dangerouslySetInnerHTML: {
-          __html: mem[id]
-        }
-      }))
-    }
+  for (const [id, c] of mem) {
+    arr.push(React.createElement('style', {
+      id: `__jsx-style-${id}`,
+      // avoid warnings upon render with a key
+      key: `__jsx-style-${id}`,
+      dangerouslySetInnerHTML: {
+        __html: c.props.css
+      }
+    }))
   }
   return arr
 }
@@ -24,10 +20,8 @@ export default function flushToReact() {
 export function flushToHTML() {
   const mem = flush()
   let html = ''
-  for (const id in mem) {
-    if (hasOwnProperty.call(mem, id)) {
-      html += `<style id="__jsx-style-${id}">${mem[id]}</style>`
-    }
+  for (const [id, c] of mem) {
+    html += `<style id="__jsx-style-${id}">${c.props.css}</style>`
   }
   return html
 }
diff --git a/src/style.js b/src/style.js
index fdf59b6..db8f5e9 100644
--- a/src/style.js
+++ b/src/style.js
@@ -21,15 +21,17 @@ export default class extends Component {
   }
 }
 
-export function flush() {
-  const ret = {}
-
-  for (const {props} of components) {
-    ret[props.styleId] = props.css
+function componentMap() {
+  const ret = new Map()
+  for (const c of components) {
+    ret.set(c.props.styleId, c)
   }
+  return ret
+}
 
+export function flush() {
+  const ret = componentMap()
   components = []
-
   return ret
 }
 
@@ -49,5 +51,5 @@ function unmount(component) {
 }
 
 function update() {
-  render(components)
+  render(componentMap())
 }
diff --git a/yarn.lock b/yarn.lock
index 047467a..b1e93f8 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1122,11 +1122,11 @@ babel-types@^6.18.0, babel-types@^6.19.0, babel-types@^6.21.0, babel-types@^6.22
     lodash "^4.2.0"
     to-fast-properties "^1.0.1"
 
-babylon@6.14.1, babylon@^6.11.0:
+babylon@6.14.1, babylon@^6.1.0, babylon@^6.11.0:
   version "6.14.1"
   resolved "https://registry.yarnpkg.com/babylon/-/babylon-6.14.1.tgz#956275fab72753ad9b3435d7afe58f8bf0a29815"
 
-babylon@^6.1.0, babylon@^6.15.0:
+babylon@^6.15.0:
   version "6.15.0"
   resolved "https://registry.yarnpkg.com/babylon/-/babylon-6.15.0.tgz#ba65cfa1a80e1759b0e89fb562e27dccae70348e"
 
@@ -1530,13 +1530,6 @@ defaults@^1.0.0:
   dependencies:
     clone "^1.0.2"
 
-define-properties@^1.1.2:
-  version "1.1.2"
-  resolved "https://registry.yarnpkg.com/define-properties/-/define-properties-1.1.2.tgz#83a73f2fea569898fb737193c8f873caf6d45c94"
-  dependencies:
-    foreach "^2.0.5"
-    object-keys "^1.0.8"
-
 del@^2.0.2:
   version "2.2.2"
   resolved "https://registry.yarnpkg.com/del/-/del-2.2.2.tgz#c12c981d067846c84bcaf862cff930d907ffd1a8"
@@ -1639,23 +1632,6 @@ error-ex@^1.2.0:
   dependencies:
     is-arrayish "^0.2.1"
 
-es-abstract@^1.6.1:
-  version "1.7.0"
-  resolved "https://registry.yarnpkg.com/es-abstract/-/es-abstract-1.7.0.tgz#dfade774e01bfcd97f96180298c449c8623fb94c"
-  dependencies:
-    es-to-primitive "^1.1.1"
-    function-bind "^1.1.0"
-    is-callable "^1.1.3"
-    is-regex "^1.0.3"
-
-es-to-primitive@^1.1.1:
-  version "1.1.1"
-  resolved "https://registry.yarnpkg.com/es-to-primitive/-/es-to-primitive-1.1.1.tgz#45355248a88979034b6792e19bb81f2b7975dd0d"
-  dependencies:
-    is-callable "^1.1.1"
-    is-date-object "^1.0.1"
-    is-symbol "^1.0.1"
-
 es5-ext@^0.10.7, es5-ext@^0.10.8, es5-ext@~0.10.11, es5-ext@~0.10.2, es5-ext@~0.10.7:
   version "0.10.12"
   resolved "https://registry.yarnpkg.com/es5-ext/-/es5-ext-0.10.12.tgz#aa84641d4db76b62abba5e45fd805ecbab140047"
@@ -2072,10 +2048,6 @@ for-own@^0.1.4:
   dependencies:
     for-in "^0.1.5"
 
-foreach@^2.0.5:
-  version "2.0.5"
-  resolved "https://registry.yarnpkg.com/foreach/-/foreach-2.0.5.tgz#0bee005018aeb260d0a3af3ae658dd0136ec1b99"
-
 forever-agent@~0.6.1:
   version "0.6.1"
   resolved "https://registry.yarnpkg.com/forever-agent/-/forever-agent-0.6.1.tgz#fbc71f0c41adeb37f96c577ad1ed42d8fdacca91"
@@ -2124,7 +2096,7 @@ fstream@^1.0.0, fstream@^1.0.2, fstream@~1.0.10:
     mkdirp ">=0.5 0"
     rimraf "2"
 
-function-bind@^1.0.2, function-bind@^1.1.0:
+function-bind@^1.0.2:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/function-bind/-/function-bind-1.1.0.tgz#16176714c801798e4e8f2cf7f7529467bb4a5771"
 
@@ -2605,20 +2577,12 @@ is-builtin-module@^1.0.0:
   dependencies:
     builtin-modules "^1.0.0"
 
-is-callable@^1.1.1, is-callable@^1.1.3:
-  version "1.1.3"
-  resolved "https://registry.yarnpkg.com/is-callable/-/is-callable-1.1.3.tgz#86eb75392805ddc33af71c92a0eedf74ee7604b2"
-
 is-ci@^1.0.7:
   version "1.0.10"
   resolved "https://registry.yarnpkg.com/is-ci/-/is-ci-1.0.10.tgz#f739336b2632365061a9d48270cd56ae3369318e"
   dependencies:
     ci-info "^1.0.0"
 
-is-date-object@^1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/is-date-object/-/is-date-object-1.0.1.tgz#9aa20eb6aeebbff77fbd33e74ca01b33581d3a16"
-
 is-dotfile@^1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/is-dotfile/-/is-dotfile-1.0.2.tgz#2c132383f39199f8edc268ca01b9b007d205cc4d"
@@ -2763,10 +2727,6 @@ is-redirect@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/is-redirect/-/is-redirect-1.0.0.tgz#1d03dded53bd8db0f30c26e4f95d36fc7c87dc24"
 
-is-regex@^1.0.3:
-  version "1.0.3"
-  resolved "https://registry.yarnpkg.com/is-regex/-/is-regex-1.0.3.tgz#0d55182bddf9f2fde278220aec3a75642c908637"
-
 is-relative@^0.2.1:
   version "0.2.1"
   resolved "https://registry.yarnpkg.com/is-relative/-/is-relative-0.2.1.tgz#d27f4c7d516d175fb610db84bbeef23c3bc97aa5"
@@ -2787,10 +2747,6 @@ is-stream@^1.0.0, is-stream@^1.0.1, is-stream@^1.1.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/is-stream/-/is-stream-1.1.0.tgz#12d4a3dd4e68e0b79ceb8dbc84173ae80d91ca44"
 
-is-symbol@^1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/is-symbol/-/is-symbol-1.0.1.tgz#3cc59f00025194b6ab2e38dbae6689256b660572"
-
 is-typedarray@~1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/is-typedarray/-/is-typedarray-1.0.0.tgz#e479c80858df0c1b11ddda6940f96011fcda4a9a"
@@ -3401,19 +3357,6 @@ object-assign@^4.0.1, object-assign@^4.1.0:
   version "4.1.1"
   resolved "https://registry.yarnpkg.com/object-assign/-/object-assign-4.1.1.tgz#2109adc7965887cfc05cbbd442cac8bfbb360863"
 
-object-keys@^1.0.8:
-  version "1.0.11"
-  resolved "https://registry.yarnpkg.com/object-keys/-/object-keys-1.0.11.tgz#c54601778ad560f1142ce0e01bcca8b56d13426d"
-
-object.entries@1.0.4:
-  version "1.0.4"
-  resolved "https://registry.yarnpkg.com/object.entries/-/object.entries-1.0.4.tgz#1bf9a4dd2288f5b33f3a993d257661f05d161a5f"
-  dependencies:
-    define-properties "^1.1.2"
-    es-abstract "^1.6.1"
-    function-bind "^1.1.0"
-    has "^1.0.1"
-
 object.omit@^2.0.0:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/object.omit/-/object.omit-2.0.1.tgz#1a9c744829f39dbb858c76ca3579ae2a54ebd1fa"
@@ -4307,6 +4250,10 @@ strip-json-comments@~2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/strip-json-comments/-/strip-json-comments-2.0.1.tgz#3c531942e908c2697c0ec344858c286c7ca0a60a"
 
+stylis@1.2.3:
+  version "1.2.3"
+  resolved "https://registry.yarnpkg.com/stylis/-/stylis-1.2.3.tgz#57c97b2a71f835b00b92460d751b2aca4355b91b"
+
 supports-color@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/supports-color/-/supports-color-2.0.0.tgz#535d045ce6b6363fa40117084629995e9df324c7"