diff --git a/.travis.yml b/.travis.yml
index 7378d9e..f46d487 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,6 @@
 language: node_js
 node_js:
-  - '6'
-  - '8'
+  - 10
+  - 12
+  - 14
   - 'node'
-
diff --git a/LICENSE-MIT b/LICENSE-MIT
index 0733a63..bf5d57b 100644
--- a/LICENSE-MIT
+++ b/LICENSE-MIT
@@ -1,4 +1,4 @@
-Copyright (c) 2018 Kyle Robinson Young
+Copyright (c) 2021 Kyle Robinson Young
 
 Permission is hereby granted, free of charge, to any person
 obtaining a copy of this software and associated documentation
diff --git a/gulpfile.js b/gulpfile.js
index 1165cd8..2a61fe7 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -1,13 +1,14 @@
-var gulp = require('gulp');
-var webpack = require('./');
-var rimraf = require('rimraf');
-var named = require('vinyl-named');
+const gulp = require('gulp');
+const webpack = require('./');
+const rimraf = require('rimraf');
+const named = require('vinyl-named');
 
 gulp.task('default', function () {
   rimraf.sync('tmp');
   return gulp.src(['test/fixtures/entry.js', 'test/fixtures/anotherentrypoint.js'])
     .pipe(named())
     .pipe(webpack({
+      mode: 'production',
       devtool: 'source-map'
     }))
     .pipe(gulp.dest('tmp/'));
diff --git a/index.js b/index.js
index 5f092d6..f4b63bf 100644
--- a/index.js
+++ b/index.js
@@ -1,16 +1,16 @@
 'use strict';
 
-var fancyLog = require('fancy-log');
-var PluginError = require('plugin-error');
-var supportsColor = require('supports-color');
-var File = require('vinyl');
-var MemoryFileSystem = require('memory-fs');
-var nodePath = require('path');
-var through = require('through');
-var ProgressPlugin = require('webpack/lib/ProgressPlugin');
-var clone = require('lodash.clone');
-
-var defaultStatsOptions = {
+const fancyLog = require('fancy-log');
+const PluginError = require('plugin-error');
+const supportsColor = require('supports-color');
+const File = require('vinyl');
+const MemoryFileSystem = require('memory-fs');
+const nodePath = require('path');
+const through = require('through');
+const ProgressPlugin = require('webpack/lib/ProgressPlugin');
+const clone = require('lodash.clone');
+
+const defaultStatsOptions = {
   colors: supportsColor.stdout.hasBasic,
   hash: false,
   timings: false,
@@ -26,32 +26,42 @@ var defaultStatsOptions = {
   errorDetails: false
 };
 
-var cache = {};
-
 module.exports = function (options, wp, done) {
-  if (cache.wp !== wp || cache.options !== options) {
-    cache = {};
+  const cache = {
+    options: options,
+    wp: wp
+  };
+
+  options = clone(options) || {};
+  const config = options.config || options;
+
+  const isInWatchMode = !!options.watch;
+  delete options.watch;
+
+  if (typeof config === 'string') {
+    config = require(config);
   }
 
-  cache.options = options;
-  cache.wp = wp;
+  // Webpack 4 doesn't support the `quiet` attribute, however supports
+  // setting `stats` to a string within an array of configurations
+  // (errors-only|minimal|none|normal|verbose) or an object with an absurd
+  // amount of config
+  const isSilent = options.quiet || (typeof options.stats === 'string' && (options.stats.match(/^(errors-only|minimal|none)$/)));
 
-  options = clone(options) || {};
-  var config = options.config || options;
   if (typeof done !== 'function') {
-    var callingDone = false;
+    let callingDone = false;
     done = function (err, stats) {
       if (err) {
         // The err is here just to match the API but isnt used
         return;
       }
       stats = stats || {};
-      if (options.quiet || callingDone) {
+      if (isSilent || callingDone) {
         return;
       }
 
       // Debounce output a little for when in watch mode
-      if (options.watch) {
+      if (isInWatchMode) {
         callingDone = true;
         setTimeout(function () {
           callingDone = false;
@@ -63,7 +73,7 @@ module.exports = function (options, wp, done) {
           colors: supportsColor.stdout.hasBasic
         }));
       } else {
-        var statsOptions = (options && options.stats) || {};
+        const statsOptions = (options && options.stats) || {};
 
         if (typeof statsOptions === 'object') {
           Object.keys(defaultStatsOptions).forEach(function (key) {
@@ -72,7 +82,7 @@ module.exports = function (options, wp, done) {
             }
           });
         }
-        var statusLog = stats.toString(statsOptions);
+        const statusLog = stats.toString(statsOptions);
         if (statusLog) {
           fancyLog(statusLog);
         }
@@ -80,11 +90,11 @@ module.exports = function (options, wp, done) {
     };
   }
 
-  var webpack = wp || require('webpack');
-  var entry = [];
-  var entries = Object.create(null);
+  const webpack = wp || require('webpack');
+  let entry = [];
+  const entries = Object.create(null);
 
-  var stream = through(function (file) {
+  const stream = through(function (file) {
     if (file.isNull()) {
       return;
     }
@@ -98,10 +108,9 @@ module.exports = function (options, wp, done) {
       entry.push(file.path);
     }
   }, function () {
-    var self = this;
-    var handleConfig = function (config) {
+    const self = this;
+    const handleConfig = function (config) {
       config.output = config.output || {};
-      config.watch = !!options.watch;
 
       // Determine pipe'd in entry
       if (Object.keys(entries).length > 0) {
@@ -127,9 +136,9 @@ module.exports = function (options, wp, done) {
       return true;
     };
 
-    var succeeded;
+    let succeeded;
     if (Array.isArray(config)) {
-      for (var i = 0; i < config.length; i++) {
+      for (let i = 0; i < config.length; i++) {
         succeeded = handleConfig(config[i]);
         if (!succeeded) {
           return false;
@@ -143,7 +152,7 @@ module.exports = function (options, wp, done) {
     }
 
     // Cache compiler for future use
-    var compiler = cache.compiler || webpack(config);
+    const compiler = cache.compiler || webpack(config);
     cache.compiler = compiler;
 
     const callback = function (err, stats) {
@@ -151,33 +160,54 @@ module.exports = function (options, wp, done) {
         self.emit('error', new PluginError('webpack-stream', err));
         return;
       }
-      var jsonStats = stats ? stats.toJson() || {} : {};
-      var errors = jsonStats.errors || [];
+      const jsonStats = stats ? stats.toJson() || {} : {};
+      const errors = jsonStats.errors || [];
       if (errors.length) {
-        var errorMessage = errors.join('\n');
-        var compilationError = new PluginError('webpack-stream', errorMessage);
-        if (!options.watch) {
+        const resolveErrorMessage = (err) => {
+          if (
+            typeof err === 'object' &&
+            err !== null &&
+            Object.prototype.hasOwnProperty.call(err, 'message')
+          ) {
+            return err.message;
+          } else if (
+            typeof err === 'object' &&
+            err !== null &&
+            'toString' in err &&
+            err.toString() !== '[object Object]'
+          ) {
+            return err.toString();
+          } else if (Array.isArray(err)) {
+            return err.map(resolveErrorMessage).join('\n');
+          } else {
+            return err;
+          }
+        };
+
+        const errorMessage = errors.map(resolveErrorMessage).join('\n');
+        const compilationError = new PluginError('webpack-stream', errorMessage);
+        if (!isInWatchMode) {
           self.emit('error', compilationError);
         }
         self.emit('compilation-error', compilationError);
       }
-      if (!options.watch) {
+      if (!isInWatchMode) {
         self.queue(null);
       }
       done(err, stats);
-      if (options.watch && !options.quiet) {
+      if (isInWatchMode && !isSilent) {
         fancyLog('webpack is watching for changes');
       }
     };
 
-    if (options.watch) {
-      const watchOptions = {};
+    if (isInWatchMode) {
+      const watchOptions = options.watchOptions || {};
       compiler.watch(watchOptions, callback);
     } else {
       compiler.run(callback);
     }
 
-    var handleCompiler = function (compiler) {
+    const handleCompiler = function (compiler) {
       if (options.progress) {
         (new ProgressPlugin(function (percentage, msg) {
           percentage = Math.floor(percentage * 100);
@@ -189,21 +219,17 @@ module.exports = function (options, wp, done) {
 
       cache.mfs = cache.mfs || new MemoryFileSystem();
 
-      var fs = compiler.outputFileSystem = cache.mfs;
+      const fs = compiler.outputFileSystem = cache.mfs;
 
-      var afterEmitPlugin = compiler.hooks
+      const assetEmittedPlugin = compiler.hooks
         // Webpack 4
-        ? function (callback) { compiler.hooks.afterEmit.tapAsync('WebpackStream', callback); }
+        ? function (callback) { compiler.hooks.assetEmitted.tapAsync('WebpackStream', callback); }
         // Webpack 2/3
-        : function (callback) { compiler.plugin('after-emit', callback); };
+        : function (callback) { compiler.plugin('asset-emitted', callback); };
 
-      afterEmitPlugin(function (compilation, callback) {
-        Object.keys(compilation.assets).forEach(function (outname) {
-          if (compilation.assets[outname].emitted) {
-            var file = prepareFile(fs, compiler, outname);
-            self.queue(file);
-          }
-        });
+      assetEmittedPlugin(function (outname, _, callback) {
+        const file = prepareFile(fs, compiler, outname);
+        self.queue(file);
         callback();
       });
     };
@@ -215,10 +241,23 @@ module.exports = function (options, wp, done) {
     } else {
       handleCompiler(compiler);
     }
+
+    if (options.watch && !isSilent) {
+      const watchRunPlugin = compiler.hooks
+        // Webpack 4
+        ? callback => compiler.hooks.watchRun.tapAsync('WebpackInfo', callback)
+        // Webpack 2/3
+        : callback => compiler.plugin('watch-run', callback);
+
+      watchRunPlugin((compilation, callback) => {
+        fancyLog('webpack compilation starting...');
+        callback();
+      });
+    }
   });
 
   // If entry point manually specified, trigger that
-  var hasEntry = Array.isArray(config)
+  const hasEntry = Array.isArray(config)
     ? config.some(function (c) { return c.entry; })
     : config.entry;
   if (hasEntry) {
@@ -229,14 +268,14 @@ module.exports = function (options, wp, done) {
 };
 
 function prepareFile (fs, compiler, outname) {
-  var path = fs.join(compiler.outputPath, outname);
+  let path = fs.join(compiler.outputPath, outname);
   if (path.indexOf('?') !== -1) {
     path = path.split('?')[0];
   }
 
-  var contents = fs.readFileSync(path);
+  const contents = fs.readFileSync(path);
 
-  var file = new File({
+  const file = new File({
     base: compiler.outputPath,
     path: nodePath.join(compiler.outputPath, outname),
     contents: contents
diff --git a/package.json b/package.json
index 4e41e7a..c02d775 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "webpack-stream",
-  "version": "5.1.1",
+  "version": "6.1.2",
   "description": "Run webpack as a stream",
   "license": "MIT",
   "homepage": "https://github.com/shama/webpack-stream",
@@ -11,33 +11,47 @@
     "url": "http://dontkry.com"
   },
   "engines": {
-    "node": ">= 6.11.5"
+    "node": ">= 10.0.0"
   },
   "scripts": {
+    "start": "gulp",
+    "debug": "node --inspect-brk ./node_modules/.bin/gulp",
     "test": "semistandard && node test/test.js"
   },
-  "files": ["index.js"],
+  "files": [
+    "index.js"
+  ],
   "semistandard": {
-    "ignore": ["test/fixtures", "examples"]
+    "ignore": [
+      "test/fixtures",
+      "examples"
+    ]
   },
   "dependencies": {
-    "fancy-log": "^1.3.2",
+    "fancy-log": "^1.3.3",
     "lodash.clone": "^4.3.2",
     "lodash.some": "^4.2.2",
-    "memory-fs": "^0.4.1",
+    "memory-fs": "^0.5.0",
     "plugin-error": "^1.0.1",
-    "supports-color": "^5.3.0",
+    "supports-color": "^8.1.1",
     "through": "^2.3.8",
-    "vinyl": "^2.1.0",
-    "webpack": "^4.7.0"
+    "vinyl": "^2.2.1"
   },
   "devDependencies": {
-    "gulp": "^3.9.0",
-    "rimraf": "^2.4.4",
-    "semistandard": "^12.0.1",
-    "tape": "^4.9.0",
+    "gulp": "^4.0.2",
+    "rimraf": "^3.0.2",
+    "semistandard": "^16.0.1",
+    "tape": "^5.3.1",
     "vinyl-fs": "^3.0.2",
-    "vinyl-named": "^1.1.0"
+    "vinyl-named": "^1.1.0",
+    "webpack": "^5.21.2"
   },
-  "keywords": ["gulpplugin", "webpack", "stream"]
+  "peerDependencies": {
+    "webpack": "^5.21.2"
+  },
+  "keywords": [
+    "gulpplugin",
+    "webpack",
+    "stream"
+  ]
 }
diff --git a/readme.md b/readme.md
index 28801ab..bdaeca9 100644
--- a/readme.md
+++ b/readme.md
@@ -83,9 +83,9 @@ To use gulp `watch`, it's required that you explicitly pass webpack in the 2nd a
 Please note that gulp `watch` and webpack `watch` are mutually exclusive.
 
 ```javascript
-var gulp = require('gulp');
-var compiler = require('webpack');
-var webpack = require('webpack-stream');
+const gulp = require('gulp');
+const compiler = require('webpack');
+const webpack = require('webpack-stream');
 
 gulp.task('build', function() {
   return gulp.src('src/entry.js')
@@ -235,5 +235,5 @@ gulp.task('default', function() {
 * 0.1.0 - Initial release
 
 ## License
-Copyright (c) 2018 Kyle Robinson Young  
+Copyright (c) 2021 Kyle Robinson Young
 Licensed under the MIT license.
diff --git a/test/fake-error-loader.js b/test/fake-error-loader.js
index 676bb89..2a5177e 100644
--- a/test/fake-error-loader.js
+++ b/test/fake-error-loader.js
@@ -1,10 +1,10 @@
-module.exports = function fakeErrorLoader (text) {
-  this.cacheable();
-
-  var fakeError = new Error('Fake error');
-  // delete stack trace prevent it from showing up in webpack output
-  delete fakeError.stack;
-  this.emitError(fakeError);
-
-  return text;
-};
+module.exports = function fakeErrorLoader (text) {
+  this.cacheable();
+
+  const fakeError = new Error('Fake error');
+  // delete stack trace prevent it from showing up in webpack output
+  delete fakeError.stack;
+  this.emitError(fakeError);
+
+  return text;
+};
diff --git a/test/fixtures/webpack.config.js b/test/fixtures/webpack.config.js
new file mode 100644
index 0000000..9be46b3
--- /dev/null
+++ b/test/fixtures/webpack.config.js
@@ -0,0 +1,7 @@
+// Test config file for 'option file path' test.
+const config = {
+  input: './entry.js'
+  // input: './nope.js'
+};
+
+module.exports = config;
diff --git a/test/test.js b/test/test.js
index 61feaca..bd54122 100644
--- a/test/test.js
+++ b/test/test.js
@@ -1,15 +1,15 @@
-var test = require('tape');
-var webpack = require('../');
-var path = require('path');
-var fs = require('vinyl-fs');
-var named = require('vinyl-named');
+const test = require('tape');
+const webpack = require('../');
+const path = require('path');
+const fs = require('vinyl-fs');
+const named = require('vinyl-named');
 
-var base = path.resolve(__dirname, 'fixtures');
+const base = path.resolve(__dirname, 'fixtures');
 
 test('streams output assets', function (t) {
   t.plan(3);
-  var entry = fs.src('test/fixtures/entry.js');
-  var stream = webpack({
+  const entry = fs.src('test/fixtures/entry.js');
+  const stream = webpack({
     config: {
       mode: 'development',
       output: {
@@ -19,14 +19,14 @@ test('streams output assets', function (t) {
     quiet: true
   });
   stream.on('data', function (file) {
-    var basename = path.basename(file.path);
-    var contents = file.contents.toString();
+    const basename = path.basename(file.path);
+    const contents = file.contents.toString();
     switch (basename) {
       case 'bundle.js':
         t.ok(/__webpack_require__/i.test(contents), 'should contain "__webpack_require__"');
         t.ok(/var one = true;/i.test(contents), 'should contain "var one = true;"');
         break;
-      case '0.bundle.js':
+      case 'test_fixtures_chunk_js.bundle.js':
         t.ok(/var chunk = true;/i.test(contents), 'should contain "var chunk = true;"');
         break;
     }
@@ -36,12 +36,12 @@ test('streams output assets', function (t) {
 
 test('multiple entry points', function (t) {
   t.plan(3);
-  var stream = webpack({
+  const stream = webpack({
     config: {
       mode: 'development',
       entry: {
-        'one': path.join(base, 'entry.js'),
-        'two': path.join(base, 'anotherentrypoint.js')
+        one: path.join(base, 'entry.js'),
+        two: path.join(base, 'anotherentrypoint.js')
       },
       output: {
         filename: '[name].bundle.js'
@@ -50,42 +50,8 @@ test('multiple entry points', function (t) {
     quiet: true
   });
   stream.on('data', function (file) {
-    var basename = path.basename(file.path);
-    var contents = file.contents.toString();
-    switch (basename) {
-      case 'one.bundle.js':
-        t.ok(/__webpack_require__/i.test(contents), 'should contain "__webpack_require__"');
-        t.ok(/var one = true;/i.test(contents), 'should contain "var one = true;"');
-        break;
-      case 'two.bundle.js':
-        t.ok(/var anotherentrypoint = true;/i.test(contents), 'should contain "var anotherentrypoint = true;"');
-        break;
-    }
-  });
-  stream.end();
-});
-
-test('subsequent runs served from cache', function (t) {
-  t.plan(4);
-
-  var config = {
-    config: {
-      mode: 'development',
-      entry: {
-        'one': path.join(base, 'entry.js'),
-        'two': path.join(base, 'anotherentrypoint.js')
-      },
-      output: {
-        filename: '[name].bundle.js'
-      }
-    },
-    quiet: true
-  };
-
-  var stream = webpack(config);
-  stream.on('data', function (file) {
-    var basename = path.basename(file.path);
-    var contents = file.contents.toString();
+    const basename = path.basename(file.path);
+    const contents = file.contents.toString();
     switch (basename) {
       case 'one.bundle.js':
         t.ok(/__webpack_require__/i.test(contents), 'should contain "__webpack_require__"');
@@ -96,35 +62,21 @@ test('subsequent runs served from cache', function (t) {
         break;
     }
   });
-
-  stream.on('end', function () {
-    var cachedStream = webpack(config);
-    var data = null;
-
-    cachedStream.on('data', function (file) {
-      data = file;
-    });
-
-    cachedStream.on('end', function () {
-      t.ok(data === null, 'should not write any output');
-    });
-  });
-
   stream.end();
 });
 
 test('stream multiple entry points', function (t) {
   t.plan(3);
-  var entries = fs.src(['test/fixtures/entry.js', 'test/fixtures/anotherentrypoint.js']);
-  var stream = webpack({
+  const entries = fs.src(['test/fixtures/entry.js', 'test/fixtures/anotherentrypoint.js']);
+  const stream = webpack({
     config: {
       mode: 'development'
     },
     quiet: true
   });
   stream.on('data', function (file) {
-    var basename = path.basename(file.path);
-    var contents = file.contents.toString();
+    const basename = path.basename(file.path);
+    const contents = file.contents.toString();
     switch (basename) {
       case 'entry.js':
         t.ok(/__webpack_require__/i.test(contents), 'should contain "__webpack_require__"');
@@ -141,12 +93,12 @@ test('stream multiple entry points', function (t) {
 test('empty input stream', function (t) {
   t.plan(1);
 
-  var entry = fs.src('test/path/to/nothing', { allowEmpty: true });
-  var stream = webpack({
+  const entry = fs.src('test/path/to/nothing', { allowEmpty: true });
+  const stream = webpack({
     config: {},
     quiet: true
   });
-  var data = null;
+  let data = null;
 
   stream.on('data', function (file) {
     data = file;
@@ -162,12 +114,12 @@ test('empty input stream', function (t) {
 test('multi-compile', function (t) {
   t.plan(3);
 
-  var stream = webpack({
+  const stream = webpack({
     quiet: true,
     config: [{
       mode: 'development',
       entry: {
-        'one': path.join(base, 'entry.js')
+        one: path.join(base, 'entry.js')
       },
       output: {
         filename: '[name].bundle.js'
@@ -175,7 +127,7 @@ test('multi-compile', function (t) {
     }, {
       mode: 'development',
       entry: {
-        'two': path.join(base, 'anotherentrypoint.js')
+        two: path.join(base, 'anotherentrypoint.js')
       },
       output: {
         filename: '[name].bundle.js'
@@ -183,8 +135,8 @@ test('multi-compile', function (t) {
     }]
   });
   stream.on('data', function (file) {
-    var basename = path.basename(file.path);
-    var contents = file.contents.toString();
+    const basename = path.basename(file.path);
+    const contents = file.contents.toString();
     switch (basename) {
       case 'one.bundle.js':
         t.ok(/__webpack_require__/i.test(contents), 'should contain "__webpack_require__"');
@@ -200,20 +152,32 @@ test('multi-compile', function (t) {
 
 test('no options', function (t) {
   t.plan(1);
-  var stream = webpack();
+  const stream = webpack();
   stream.on('end', function () {
     t.ok(true, 'ended without error');
   });
   stream.end();
 });
 
+test('config file path with webpack-stream options', function (t) {
+  t.plan(1);
+  var stream = webpack({
+    quiet: true,
+    config: path.join(base, 'webpack.config.js')
+  });
+  stream.on('end', function () {
+    t.ok(true, 'config successfully loaded from file, with webpack-stream options');
+  });
+  stream.end();
+});
+
 test('error formatting', function (t) {
   t.plan(2);
   // TODO: Fix this to test to rely less on large string outputs as those can change
   // and still be ok.
-  var expectedMessage = '\x1b[31mError\x1b[39m in plugin "\x1b[36mwebpack-stream\x1b[39m"\nMessage:\n    ./test/fixtures/entry.js\nModule Error (from ./test/fak';
-  var entry = fs.src('test/fixtures/entry.js');
-  var stream = webpack({
+  const expectedMessage = '\x1b[31mError\x1b[39m in plugin "\x1b[36mwebpack-stream\x1b[39m"\nMessage:\n    Module Error (from ./test/fake-error-loader.js):\nFake ';
+  const entry = fs.src('test/fixtures/entry.js');
+  const stream = webpack({
     quiet: true,
     config: {
       module: {