diff --git a/lib/helpers/immediate.js b/lib/helpers/immediate.js
index 0a1c26c32f6..73085f7d420 100644
--- a/lib/helpers/immediate.js
+++ b/lib/helpers/immediate.js
@@ -7,7 +7,9 @@
 
 'use strict';
 
-const nextTick = process.nextTick.bind(process);
+const nextTick = typeof process !== 'undefined' && typeof process.nextTick === 'function' ?
+  process.nextTick.bind(process) :
+  cb => setTimeout(cb, 0); // Fallback for browser build
 
 module.exports = function immediate(cb) {
   return nextTick(cb);
diff --git a/lib/helpers/isAsyncFunction.js b/lib/helpers/isAsyncFunction.js
index 2a136dcd934..998705304a9 100644
--- a/lib/helpers/isAsyncFunction.js
+++ b/lib/helpers/isAsyncFunction.js
@@ -1,10 +1,22 @@
 'use strict';
 
-const asyncFunctionPrototype = Object.getPrototypeOf(async function() {});
+let asyncFunctionPrototype = null;
+// try/catch for Babel compatibility, because Babel preset-env requires
+// regenerator-runtime for async/await and we don't want to include that
+// for a simple check.
+try {
+  asyncFunctionPrototype = Object.getPrototypeOf(async function() {});
+} catch (err) {}
 
-module.exports = function isAsyncFunction(v) {
-  return (
-    typeof v === 'function' &&
-    Object.getPrototypeOf(v) === asyncFunctionPrototype
-  );
-};
+if (asyncFunctionPrototype == null) {
+  module.exports = function isAsyncFunction() {
+    return false;
+  };
+} else {
+  module.exports = function isAsyncFunction(v) {
+    return (
+      typeof v === 'function' &&
+      Object.getPrototypeOf(v) === asyncFunctionPrototype
+    );
+  };
+}
diff --git a/package.json b/package.json
index 05653305ae9..6c73e1ea0f9 100644
--- a/package.json
+++ b/package.json
@@ -40,6 +40,7 @@
     "babel-loader": "8.2.4",
     "benchmark": "2.1.4",
     "bluebird": "3.7.2",
+    "buffer": "6.0.3",
     "cheerio": "1.0.0-rc.10",
     "crypto-browserify": "3.12.0",
     "dox": "0.3.1",
diff --git a/webpack.config.js b/webpack.config.js
index ea65591e8d0..ebecbab2f84 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -1,5 +1,6 @@
 'use strict';
 
+const webpack = require('webpack');
 const paths = require('path');
 
 const webpackConfig = {
@@ -35,12 +36,21 @@ const webpackConfig = {
   resolve: {
     fallback: {
       assert: require.resolve('assert-browserify'),
+      buffer: require.resolve('buffer/'),
       crypto: require.resolve('crypto-browserify'),
       stream: require.resolve('stream-browserify')
     }
   },
   target: 'web',
-  mode: 'production'
+  mode: 'production',
+  plugins: [
+    new webpack.DefinePlugin({
+      process: '({env:{}})'
+    }),
+    new webpack.ProvidePlugin({
+      Buffer: ['buffer', 'Buffer']
+    })
+  ]
 };
 
 module.exports = webpackConfig;