diff --git a/lib/CompatibilityPlugin.ts b/lib/CompatibilityPlugin.ts
index c503ab66812..94b0dc837c5 100644
--- a/lib/CompatibilityPlugin.ts
+++ b/lib/CompatibilityPlugin.ts
@@ -8,9 +8,12 @@ import Compiler = require('./Compiler')
 import Compilation = require('./Compilation')
 import Parser = require('./Parser')
 import { CallExpression } from 'estree'
-import { CompilationParams, ParserOptions } from '../typings/webpack-types'
+import { CompilationParams, ParserOptions, NMFAfterResolveResult } from '../typings/webpack-types'
 import ContextDependency = require('./dependencies/ContextDependency')
 
+const jsonLoaderPath = require.resolve('json-loader');
+const matchJson = /\.json$/i;
+
 class CompatibilityPlugin {
     apply(compiler: Compiler) {
         compiler.plugin('compilation', function (compilation: Compilation, params: CompilationParams) {
@@ -48,6 +51,16 @@ class CompatibilityPlugin {
                     return true;
                 });
             });
+            params.normalModuleFactory.plugin('after-resolve', function (data: NMFAfterResolveResult, done) {
+                // if this is a json file and there are no loaders active, we use the json-loader in order to avoid
+                // parse errors @see https://github.com/webpack/webpack/issues/3363
+                if (matchJson.test(data.request) && data.loaders.length === 0) {
+                    data.loaders.push({
+                        loader: jsonLoaderPath
+                    });
+                }
+                done(null, data);
+            });
         });
     }
 }
diff --git a/lib/Compilation.ts b/lib/Compilation.ts
index 3e02a2a71fe..420e8345814 100644
--- a/lib/Compilation.ts
+++ b/lib/Compilation.ts
@@ -12,7 +12,9 @@ import {
     ErrCallback,
     PlainObject,
     TimeStampMap,
-    WebpackError, AbstractInputFileSystem
+    WebpackError,
+    AbstractInputFileSystem,
+    PerformanceOptions
 } from '../typings/webpack-types'
 import { ResolveError } from 'enhanced-resolve/lib/common-types'
 import async = require('async');
@@ -36,7 +38,6 @@ import ChunkRenderError = require('./ChunkRenderError');
 import NormalModule = require('./NormalModule')
 import DependenciesBlock = require('./DependenciesBlock')
 import AsyncDependenciesBlock = require('./AsyncDependenciesBlock')
-import * as Resolve from 'enhanced-resolve'
 
 interface SlotChunk {
     name: string
@@ -82,6 +83,7 @@ class Compilation extends Tapable {
     options: WebpackOptions
     outputOptions: WebpackOutputOptions
     preparedChunks: SlotChunk[]
+    performance: PerformanceOptions
     profile: boolean
     records: Record
     resolvers: Compiler.Resolvers
@@ -99,6 +101,7 @@ class Compilation extends Tapable {
         this.outputOptions = options && options.output;
         this.bail = options && options.bail;
         this.profile = options && options.profile;
+        this.performance = options && options.performance;
 
         this.mainTemplate = new MainTemplate(this.outputOptions);
         this.chunkTemplate = new ChunkTemplate(this.outputOptions);
@@ -437,12 +440,12 @@ class Compilation extends Tapable {
         const start = this.profile && +new Date();
 
         const errorAndCallback = this.bail ? function errorAndCallback(err: ModuleNotFoundError) {
-            callback(err);
-        } : function errorAndCallback(err: ModuleNotFoundError) {
-            err.dependencies = [dependency];
-            this.errors.push(err);
-            callback();
-        }.bind(this);
+                callback(err);
+            } : function errorAndCallback(err: ModuleNotFoundError) {
+                err.dependencies = [dependency];
+                this.errors.push(err);
+                callback();
+            }.bind(this);
 
         if (typeof dependency !== 'object' || dependency === null || !dependency.constructor) {
             throw new Error('Parameter \'dependency\' must be a Dependency');
@@ -1083,7 +1086,7 @@ class Compilation extends Tapable {
             let source;
             let file;
             const filenameTemplate = chunk.filenameTemplate
-                ? chunk.filenameTemplate as string
+                ? chunk.filenameTemplate
                 : chunk.isInitial() ? filename : chunkFilename;
             try {
                 const useChunkHash = !chunk.hasRuntime() || this.mainTemplate.useChunkHash && this.mainTemplate.useChunkHash(chunk);
@@ -1156,6 +1159,7 @@ declare namespace Compilation {
         __SourceMapDevToolData?: Dictionary<RawSource | ConcatSource>
         emitted?: boolean
         existsAt?: string
+        isOverSizeLimit?: boolean
     }
 }
 
diff --git a/lib/Compiler.ts b/lib/Compiler.ts
index 59d5f87b3c8..cb4e4e6f72a 100644
--- a/lib/Compiler.ts
+++ b/lib/Compiler.ts
@@ -20,7 +20,8 @@ import {
     TimeStampMap,
     WatchFileSystem,
     WatchOptions,
-    AbstractInputFileSystem, AbstractStats
+    AbstractInputFileSystem,
+    AbstractStats
 } from '../typings/webpack-types'
 import Parser = require('./Parser')
 import Stats = require('./Stats')
diff --git a/lib/ContextModule.ts b/lib/ContextModule.ts
index 4f8fa483f91..e6abe06869c 100644
--- a/lib/ContextModule.ts
+++ b/lib/ContextModule.ts
@@ -10,7 +10,6 @@ import AsyncDependenciesBlock = require('./AsyncDependenciesBlock');
 import ModuleDependency = require('./dependencies/ModuleDependency');
 import RequestShortener = require('./RequestShortener')
 import Compilation = require('./Compilation')
-import * as Resolve from 'enhanced-resolve'
 
 class ContextModule extends Module {
     async: boolean
@@ -90,7 +89,10 @@ class ContextModule extends Module {
         super.disconnect();
     }
 
-    build(options: WebpackOptions, compilation: Compilation, resolver: any, fs: AbstractInputFileSystem, callback: ErrCallback) {
+    build(
+        options: WebpackOptions, compilation: Compilation, resolver: any, fs: AbstractInputFileSystem,
+        callback: ErrCallback
+    ) {
         this.built = true;
         this.builtTime = new Date().getTime();
         const addon = this.addon;
diff --git a/lib/ContextModuleFactory.ts b/lib/ContextModuleFactory.ts
index 204ab29f1cc..6b8fd9a4edd 100644
--- a/lib/ContextModuleFactory.ts
+++ b/lib/ContextModuleFactory.ts
@@ -8,10 +8,14 @@ import Tapable = require('tapable');
 import ContextModule = require('./ContextModule');
 import ContextElementDependency = require('./dependencies/ContextElementDependency');
 import ContextDependency = require('./dependencies/ContextDependency')
-import { CMFBeforeResolveResult, ErrCallback, AlternativeModule, AbstractInputFileSystem } from '../typings/webpack-types'
+import {
+    CMFBeforeResolveResult,
+    ErrCallback,
+    AlternativeModule,
+    AbstractInputFileSystem
+} from '../typings/webpack-types'
 import { Stats } from 'fs'
 import Compiler = require('./Compiler')
-import * as Resolve from 'enhanced-resolve'
 
 class ContextModuleFactory extends Tapable {
     constructor(public resolvers: Compiler.Resolvers) {
@@ -126,7 +130,10 @@ class ContextModuleFactory extends Tapable {
         });
     }
 
-    resolveDependencies(fs: AbstractInputFileSystem, resource: string, recursive: boolean, regExp: RegExp, callback: ErrCallback) {
+    resolveDependencies(
+        fs: AbstractInputFileSystem, resource: string, recursive: boolean, regExp: RegExp,
+        callback: ErrCallback
+    ) {
         if (!regExp || !resource) {
             return callback(null, []);
         }
diff --git a/lib/ContextReplacementPlugin.ts b/lib/ContextReplacementPlugin.ts
index 9819dca5185..41e9df76921 100644
--- a/lib/ContextReplacementPlugin.ts
+++ b/lib/ContextReplacementPlugin.ts
@@ -8,7 +8,9 @@ import Compiler = require('./Compiler')
 import ContextModuleFactory = require('./ContextModuleFactory')
 import ContextDependency = require('./dependencies/ContextDependency')
 import {
-    CMFAfterResolveResult, CMFBeforeResolveResult, ErrCallback,
+    CMFAfterResolveResult,
+    CMFBeforeResolveResult,
+    ErrCallback,
     AbstractInputFileSystem
 } from '../typings/webpack-types'
 import * as Resolve from 'enhanced-resolve'
diff --git a/lib/Entrypoint.ts b/lib/Entrypoint.ts
index 6a0bee11186..9b38768e0c0 100644
--- a/lib/Entrypoint.ts
+++ b/lib/Entrypoint.ts
@@ -3,6 +3,7 @@
  Author Tobias Koppers @sokra
  */
 import Chunk = require('./Chunk')
+import Compilation = require('./Compilation')
 
 class Entrypoint {
     chunks: Chunk[]
@@ -26,6 +27,28 @@ class Entrypoint {
         }
         chunk.entrypoints.push(this);
     }
+
+    getFiles() {
+        const files: string[] = [];
+
+        for (let chunk of this.chunks) {
+            for (let file of chunk.files) {
+                if (!files.includes(file)) {
+                    files.push(file)
+                }
+            }
+        }
+
+        return files;
+    }
+
+    getSize(compilation: Compilation) {
+        const files = this.getFiles();
+
+        return files
+            .map(file => compilation.assets[file].size())
+            .reduce((currentSize, nextSize) => currentSize + nextSize, 0);
+    }
 }
 
 export = Entrypoint;
diff --git a/lib/JsonpMainTemplatePlugin.ts b/lib/JsonpMainTemplatePlugin.ts
index 8f10fb5e830..e2c9393734f 100644
--- a/lib/JsonpMainTemplatePlugin.ts
+++ b/lib/JsonpMainTemplatePlugin.ts
@@ -142,15 +142,15 @@ class JsonpMainTemplatePlugin {
                         'while(resolves.length)',
                         this.indent('resolves.shift()();'),
                         this.entryPointInChildren(chunk) ? [
-                            'if(executeModules) {',
-                            this.indent([
-                                'for(i=0; i < executeModules.length; i++) {',
-                                this.indent(`result = ${this.requireFn}(${this.requireFn}.s = executeModules[i]);`),
-                                '}'
-                            ]),
-                            '}',
-                            'return result;'
-                        ] : ''
+                                'if(executeModules) {',
+                                this.indent([
+                                    'for(i=0; i < executeModules.length; i++) {',
+                                    this.indent(`result = ${this.requireFn}(${this.requireFn}.s = executeModules[i]);`),
+                                    '}'
+                                ]),
+                                '}',
+                                'return result;'
+                            ] : ''
                     ]),
                     '};'
                 ]);
diff --git a/lib/MainTemplate.ts b/lib/MainTemplate.ts
index bbaecbbe26d..b875e720c80 100644
--- a/lib/MainTemplate.ts
+++ b/lib/MainTemplate.ts
@@ -68,22 +68,22 @@ class MainTemplate extends Template {
                 '};',
                 '',
                 this.asString(outputOptions.strictModuleExceptionHandling ? [
-                    '// Execute the module function',
-                    'var threw = true;',
-                    'try {',
-                    this.indent([
+                        '// Execute the module function',
+                        'var threw = true;',
+                        'try {',
+                        this.indent([
+                            `modules[moduleId].call(module.exports, module, module.exports, ${this.renderRequireFunctionForModule(hash, chunk, 'moduleId')});`,
+                            'threw = false;'
+                        ]),
+                        '} finally {',
+                        this.indent([
+                            'if(threw) delete installedModules[moduleId];'
+                        ]),
+                        '}'
+                    ] : [
+                        '// Execute the module function',
                         `modules[moduleId].call(module.exports, module, module.exports, ${this.renderRequireFunctionForModule(hash, chunk, 'moduleId')});`,
-                        'threw = false;'
                     ]),
-                    '} finally {',
-                    this.indent([
-                        'if(threw) delete installedModules[moduleId];'
-                    ]),
-                    '}'
-                ] : [
-                    '// Execute the module function',
-                    `modules[moduleId].call(module.exports, module, module.exports, ${this.renderRequireFunctionForModule(hash, chunk, 'moduleId')});`,
-                ]),
                 '',
                 '// Flag the module as loaded',
                 'module.l = true;',
@@ -113,16 +113,20 @@ class MainTemplate extends Template {
             buf.push(`${this.requireFn}.c = installedModules;`);
 
             buf.push('');
-            buf.push('// identity function for calling harmory imports with the correct context');
+            buf.push('// identity function for calling harmony imports with the correct context');
             buf.push(`${this.requireFn}.i = function(value) { return value; };`);
 
             buf.push('');
-            buf.push('// define getter function for harmory exports');
+            buf.push('// define getter function for harmony exports');
             buf.push(`${this.requireFn}.d = function(exports, name, getter) {`);
             buf.push(this.indent([
-                'Object.defineProperty(exports, name, {',
-                this.indent(['configurable: false,', 'enumerable: true,', 'get: getter']),
-                '});'
+                `if(!${this.requireFn}.o(exports, name)) \{`,
+                this.indent([
+                    'Object.defineProperty(exports, name, {',
+                    this.indent(['configurable: false,', 'enumerable: true,', 'get: getter']),
+                    '});'
+                ]),
+                '}'
             ]));
             buf.push('};');
 
diff --git a/lib/Module.ts b/lib/Module.ts
index c04fd7e02eb..c3746ff01ba 100644
--- a/lib/Module.ts
+++ b/lib/Module.ts
@@ -37,6 +37,7 @@ abstract class Module extends DependenciesBlock implements IRemoveAndDo {
     meta: Module.Meta;
     optional?: boolean
     parent: Module
+    portableId: string
     prefetched: boolean
     profile?: Module.Profile
     providedExports: string[] | boolean;
@@ -56,6 +57,7 @@ abstract class Module extends DependenciesBlock implements IRemoveAndDo {
         this.debugId = debugId++;
         this.lastId = -1;
         this.id = null;
+        this.portableId = null;
         this.index = null;
         this.index2 = null;
         this.used = null;
diff --git a/lib/NormalModule.ts b/lib/NormalModule.ts
index fd8efcfcbbd..46c6c9fcec8 100644
--- a/lib/NormalModule.ts
+++ b/lib/NormalModule.ts
@@ -19,7 +19,8 @@ import {
     WebpackOutputOptions,
     TimeStampMap,
     SourceRange,
-    ErrCallback, AbstractInputFileSystem
+    ErrCallback,
+    AbstractInputFileSystem
 } from '../typings/webpack-types'
 import crypto = require('crypto')
 import path = require('path');
@@ -38,7 +39,6 @@ import DependenciesBlockVariable = require('./DependenciesBlockVariable')
 import DependenciesBlock = require('./DependenciesBlock')
 import Parser = require('./Parser')
 import Resolver = require('enhanced-resolve/lib/Resolver')
-import * as Resolve from 'enhanced-resolve'
 
 function asString(buf: string | Buffer) {
     if (Buffer.isBuffer(buf)) {
@@ -110,7 +110,10 @@ class NormalModule extends Module {
         return this.resource;
     }
 
-    doBuild(options: WebpackOptions, compilation: Compilation, resolver: Resolver, fs: AbstractInputFileSystem, callback: ErrCallback) {
+    doBuild(
+        options: WebpackOptions, compilation: Compilation, resolver: Resolver, fs: AbstractInputFileSystem,
+        callback: ErrCallback
+    ) {
         this.cacheable = false;
         const self = this;
         const loaderContext: LoaderContext = {
@@ -205,7 +208,10 @@ class NormalModule extends Module {
         super.disconnect();
     }
 
-    build(options: WebpackOptions, compilation: Compilation, resolver: Resolver, fs: AbstractInputFileSystem, callback: ErrCallback) {
+    build(
+        options: WebpackOptions, compilation: Compilation, resolver: Resolver, fs: AbstractInputFileSystem,
+        callback: ErrCallback
+    ) {
         const self = this;
         self.buildTimestamp = new Date().getTime();
         self.built = true;
diff --git a/lib/Parser.ts b/lib/Parser.ts
index 0272cd8f255..eb7ba1309d3 100644
--- a/lib/Parser.ts
+++ b/lib/Parser.ts
@@ -4,19 +4,21 @@
  */
 import * as ESTree from 'estree'
 import { PlainObject, SourceRange, ParserState } from '../typings/webpack-types'
-import acorn = require('acorn');
+import acorn from 'acorn-dynamic-import'
 import Tapable = require('tapable');
 import BasicEvaluatedExpression = require('./BasicEvaluatedExpression');
 import Module = require('./Module')
 import DependenciesBlock = require('./DependenciesBlock')
 import Compilation = require('./Compilation')
 
+// todo: once update acorn.d.ts, remove this interface
 interface ASTOPTION {
     ecmaVersion: number
     locations: boolean
     onComment: any[]
     ranges: boolean
     sourceType: string
+    plugins: any
 }
 
 interface IdentCallback {
@@ -28,12 +30,18 @@ const POSSIBLE_AST_OPTIONS = [
         ranges: true,
         locations: true,
         ecmaVersion: 2017,
-        sourceType: 'module'
+        sourceType: 'module',
+        plugins: {
+            dynamicImport: true
+        }
     }, {
         ranges: true,
         locations: true,
         ecmaVersion: 2017,
-        sourceType: 'script'
+        sourceType: 'script',
+        plugins: {
+            dynamicImport: true
+        }
     }
 ] as ASTOPTION[];
 
@@ -41,7 +49,7 @@ interface ParserScope {
     definitions: string[]
     inShorthand?: boolean
     inTry: boolean
-    renames: Dictionary<Parser>
+    renames: Dictionary<string>
 }
 
 //noinspection JSUnusedGlobalSymbols,JSMethodCanBeStatic
@@ -1112,6 +1120,16 @@ class Parser extends Tapable {
             // (function(...) { }(...))
             walkIIFE.call(this, expression.callee, expression.arguments);
         }
+        else if (expression.callee.type === 'Import') {
+            const result = this.applyPluginsBailResult1('import-call', expression);
+            if (result === true) {
+                return;
+            }
+
+            if (expression.arguments) {
+                this.walkExpressions(expression.arguments);
+            }
+        }
         else {
 
             const callee = this.evaluateExpression(expression.callee);
@@ -1335,6 +1353,9 @@ class Parser extends Tapable {
                 locations: true,
                 ecmaVersion: 2017,
                 sourceType: 'module',
+                plugins: {
+                    dynamicImport: true
+                },
                 onComment: comments
             });
         }
@@ -1362,7 +1383,10 @@ class Parser extends Tapable {
             ranges: true,
             locations: true,
             ecmaVersion: 2017,
-            sourceType: 'module'
+            sourceType: 'module',
+            plugins: {
+                dynamicImport: true
+            }
         });
         if (!ast || typeof ast !== 'object' || ast.type !== 'Program') {
             throw new Error('evaluate: Source couldn\'t be parsed');
diff --git a/lib/RecordIdsPlugin.ts b/lib/RecordIdsPlugin.ts
index fc0075f7796..4d00fafd1c7 100644
--- a/lib/RecordIdsPlugin.ts
+++ b/lib/RecordIdsPlugin.ts
@@ -24,7 +24,10 @@ class RecordIdsPlugin {
                     records.modules.usedIds = {};
                 }
                 modules.forEach(module => {
-                    const identifier = makeRelative(compiler, module.identifier());
+                    if (!module.portableId) {
+                        module.portableId = makeRelative(compiler, module.identifier());
+                    }
+                    const identifier = module.portableId;
                     records.modules.byIdentifier[identifier] = module.id;
                     records.modules.usedIds[module.id] = module.id;
                 });
@@ -39,7 +42,10 @@ class RecordIdsPlugin {
                         if (module.id !== null) {
                             return;
                         }
-                        const identifier = makeRelative(compiler, module.identifier());
+                        if (!module.portableId) {
+                            module.portableId = makeRelative(compiler, module.identifier());
+                        }
+                        const identifier = module.portableId;
                         const id = records.modules.byIdentifier[identifier];
                         if (id === undefined) {
                             return;
diff --git a/lib/SetVarMainTemplatePlugin.ts b/lib/SetVarMainTemplatePlugin.ts
index 9a372a8b81d..5a5be92a6b7 100644
--- a/lib/SetVarMainTemplatePlugin.ts
+++ b/lib/SetVarMainTemplatePlugin.ts
@@ -27,7 +27,7 @@ class SetVarMainTemplatePlugin {
             }
         });
         mainTemplate.plugin('global-hash-paths', function (paths: string[]) {
-            // todo: this is no varExpression in MainTemplate, may refer wrongly
+            // todo: this is no varExpression in MainTemplate, may refer wrongly, dead code
             if (this.varExpression) {
                 paths.push(this.varExpression);
             }
diff --git a/lib/SizeFormatHelpers.ts b/lib/SizeFormatHelpers.ts
new file mode 100644
index 00000000000..67d2ddf8a1e
--- /dev/null
+++ b/lib/SizeFormatHelpers.ts
@@ -0,0 +1,14 @@
+/*
+ MIT License http://www.opensource.org/licenses/mit-license.php
+ Author Sean Larkin @thelarkinn
+ */
+export function formatSize(size: number) {
+    if (size <= 0) {
+        return '0 bytes';
+    }
+
+    const abbreviations = ['bytes', 'kB', 'MB', 'GB'];
+    const index = Math.floor(Math.log(size) / Math.log(1000));
+
+    return `${+(size / Math.pow(1000, index)).toPrecision(3)} ${abbreviations[index]}`;
+}
diff --git a/lib/SourceMapDevToolPlugin.ts b/lib/SourceMapDevToolPlugin.ts
index 68feaa9e5f5..3c315d204b0 100644
--- a/lib/SourceMapDevToolPlugin.ts
+++ b/lib/SourceMapDevToolPlugin.ts
@@ -37,7 +37,7 @@ class SourceMapDevToolPlugin {
             throw new Error('SourceMapDevToolPlugin only takes one argument (pass an options object)');
         }
         if (typeof options === 'string') {
-            // todo: here may be an error, no usage of options.sourceMapFilename
+            // todo: here may be an error, no usage of options.sourceMapFilename, dead code
             options = {
                 sourceMapFilename: options
             } as SourceMapDevToolPlugin.Option;
diff --git a/lib/Stats.ts b/lib/Stats.ts
index 5fe980fc730..c55a6439f58 100644
--- a/lib/Stats.ts
+++ b/lib/Stats.ts
@@ -5,6 +5,7 @@
 import RequestShortener = require('./RequestShortener');
 import Compilation = require('./Compilation')
 import { StatsOptions, PlainObject, WebpackError } from '../typings/webpack-types'
+import { formatSize } from './SizeFormatHelpers'
 import Module = require('./Module')
 import NormalModule = require('./NormalModule')
 import ModuleNotFoundError = require('./ModuleNotFoundError');
@@ -96,6 +97,7 @@ interface StatsAsset {
     emitted: boolean
     name: string
     size: number
+    isOverSizeLimit?: boolean
 }
 
 interface StatsEntryPoint {
@@ -156,6 +158,7 @@ class Stats {
 
         const compilation = this.compilation;
         const requestShortener = new RequestShortener(d(options.context, process.cwd()));
+        const showPerformance = d(options.performance, true);
         const showHash = d(options.hash, true);
         const showVersion = d(options.version, true);
         const showTimings = d(options.timings, true);
@@ -193,7 +196,7 @@ class Stats {
             if (excludeModules.length === 0) {
                 return true;
             }
-            const ident = module.identifier();
+            const ident = module.resource;
             return !excludeModules.some(regExp => regExp.test(ident));
         }
 
@@ -221,14 +224,14 @@ class Stats {
         function formatError(e: WebpackError | string) {
             let text = '';
             let err: WebpackError = typeof e === 'string' ? {
-                message: e
-            } : e;
+                    message: e
+                } : e;
             if (err.chunk) {
                 text += `chunk ${err.chunk.name || err.chunk.id}${err.chunk.hasRuntime()
                     ? ' [entry]'
                     : err.chunk.isInitial()
-                    ? ' [initial]'
-                    : ''}\n`;
+                        ? ' [initial]'
+                        : ''}\n`;
             }
             if (err.file) {
                 text += `${err.file}\n`;
@@ -271,7 +274,6 @@ class Stats {
             return text;
         }
 
-        // todo: remove any type
         const obj: StatsJson = {
             errors: compilation.errors.map(formatError),
             warnings: compilation.warnings.map(formatError)
@@ -317,7 +319,12 @@ class Stats {
                         chunks: [] as number[],
                         chunkNames: [] as string[],
                         emitted: compilation.assets[asset].emitted
-                    };
+                    } as StatsAsset;
+
+                    if (showPerformance) {
+                        obj.isOverSizeLimit = compilation.assets[asset].isOverSizeLimit;
+                    }
+
                     assetsByFile[asset] = obj;
                     return obj;
                 })
@@ -357,7 +364,6 @@ class Stats {
         }
 
         function fnModule(module: NormalModule) {
-            // todo: remove any type
             const obj: StatsModule = {
                 id: module.id,
                 identifier: module.identifier(),
@@ -383,7 +389,6 @@ class Stats {
                 obj.reasons = module.reasons
                     .filter(reason => reason.dependency && reason.module)
                     .map(reason => {
-                        // todo: remove any type
                         const obj: StatsReason = {
                             moduleId: reason.module.id,
                             moduleIdentifier: reason.module.identifier(),
@@ -446,9 +451,9 @@ class Stats {
                         moduleName: origin.module ? origin.module.readableIdentifier(requestShortener) : '',
                         loc: typeof origin.loc === 'object'
                             ? (
-                            obj.loc = `${origin.loc.start.line}:${origin.loc.start.column}-${origin.loc.start.line !== origin.loc.end.line
-                                ? origin.loc.end.line + ':'
-                                : ''}${origin.loc.end.column}`)
+                                obj.loc = `${origin.loc.start.line}:${origin.loc.start.column}-${origin.loc.start.line !== origin.loc.end.line
+                                    ? origin.loc.end.line + ':'
+                                    : ''}${origin.loc.end.column}`)
                             : '',
                         name: origin.name,
                         reasons: origin.reasons || []
@@ -552,7 +557,16 @@ class Stats {
             buffer.push('\n');
         }
 
-        function table(array: string[][], formats: Function[], align: string, splitter = '  ') {
+        function getText(arr: any[], row: number, col: number) {
+            return arr[row][col].value;
+        }
+
+        type TableItem = {
+            value: string
+            color: (str: string| number) => void
+        }
+
+        function table(array: TableItem[][], align: string, splitter = '  ') {
             let row;
             const rows = array.length;
             let col;
@@ -564,7 +578,10 @@ class Stats {
             }
             for (row = 0; row < rows; row++) {
                 for (col = 0; col < cols; col++) {
-                    value = `${array[row][col]}`;
+                    value = `${getText(array, row, col)}`;
+                    if (value.length === 0) {
+                        colSizes[col] = 0;
+                    }
                     if (value.length > colSizes[col]) {
                         colSizes[col] = value.length;
                     }
@@ -572,8 +589,8 @@ class Stats {
             }
             for (row = 0; row < rows; row++) {
                 for (col = 0; col < cols; col++) {
-                    const format = row === 0 ? colors.bold : formats[col];
-                    value = `${array[row][col]}`;
+                    const format = array[row][col].color;
+                    value = `${getText(array, row, col)}`;
                     let l = value.length;
                     if (align[col] === 'l') {
                         format(value);
@@ -585,7 +602,7 @@ class Stats {
                     if (align[col] === 'r') {
                         format(value);
                     }
-                    if (col + 1 < cols) {
+                    if (col + 1 < cols && colSizes[col] != 0) {
                         colors.normal(splitter);
                     }
                 }
@@ -593,15 +610,12 @@ class Stats {
             }
         }
 
-        function formatSize(size: number) {
-            if (size <= 0) {
-                return '0 bytes';
+        function getAssetColor(asset: StatsAsset, defaultColor: (str: string| number) => void) {
+            if (asset.isOverSizeLimit) {
+                return colors.yellow;
             }
 
-            const abbreviations = ['bytes', 'kB', 'MB', 'GB'];
-            const index = Math.floor(Math.log(size) / Math.log(1000));
-
-            return `${+(size / Math.pow(1000, index)).toPrecision(3)} ${abbreviations[index]}`;
+            return defaultColor;
         }
 
         if (obj.hash) {
@@ -626,17 +640,59 @@ class Stats {
             newline();
         }
         if (obj.assets && obj.assets.length > 0) {
-            const t = [['Asset', 'Size', 'Chunks', '', 'Chunk Names']];
-            obj.assets.forEach(asset => {
+            const t = [
+                [
+                    {
+                        value: 'Asset',
+                        color: colors.bold
+                    },
+                    {
+                        value: 'Size',
+                        color: colors.bold
+                    }
+                    ,
+                    {
+                        value: 'Chunks',
+                        color: colors.bold
+                    },
+                    {
+                        value: '',
+                        color: colors.bold
+                    },
+                    {
+                        value: '',
+                        color: colors.bold
+                    },
+                    {
+                        value: 'Chunk Names',
+                        color: colors.bold
+                    }
+                ]
+            ];
+            obj.assets.forEach(function (asset) {
                 t.push([
-                    asset.name,
-                    formatSize(asset.size),
-                    asset.chunks.join(', '),
-                    asset.emitted ? '[emitted]' : '',
-                    asset.chunkNames.join(', ')
+                    {
+                        value: asset.name,
+                        color: getAssetColor(asset, colors.green)
+                    }, {
+                        value: formatSize(asset.size),
+                        color: getAssetColor(asset, colors.normal)
+                    }, {
+                        value: asset.chunks.join(', '),
+                        color: colors.bold
+                    }, {
+                        value: asset.emitted ? '[emitted]' : '',
+                        color: colors.green
+                    }, {
+                        value: asset.isOverSizeLimit ? '[big]' : '',
+                        color: getAssetColor(asset, colors.normal)
+                    }, {
+                        value: asset.chunkNames.join(', '),
+                        color: colors.normal
+                    }
                 ]);
             });
-            table(t, [colors.green, colors.normal, colors.bold, colors.green, colors.normal], 'rrrll');
+            table(t, 'rrrlll');
         }
         if (obj.entrypoints) {
             Object.keys(obj.entrypoints).forEach(name => {
@@ -725,6 +781,7 @@ class Stats {
                     colors.normal(reason.type);
                     colors.normal(' ');
                     colors.cyan(reason.userRequest);
+                    // todo: dead code
                     if (reason.templateModules) {
                         colors.cyan(reason.templateModules.join(' '));
                     }
diff --git a/lib/UmdMainTemplatePlugin.ts b/lib/UmdMainTemplatePlugin.ts
index b9d46e18281..ccd6d2b0c57 100644
--- a/lib/UmdMainTemplatePlugin.ts
+++ b/lib/UmdMainTemplatePlugin.ts
@@ -147,13 +147,13 @@ class UmdMainTemplatePlugin {
 ` +
                     (requiredExternals.length > 0
                             ? (this.name && this.namedDefine === true
-                                ? `        define(${libraryName(this.name)}, ${externalsDepsArray(requiredExternals)}, ${amdFactory});`
-                                : `        define(${externalsDepsArray(requiredExternals)}, ${amdFactory});`
-                        )
+                                    ? `        define(${libraryName(this.name)}, ${externalsDepsArray(requiredExternals)}, ${amdFactory});`
+                                    : `        define(${externalsDepsArray(requiredExternals)}, ${amdFactory});`
+                            )
                             : (this.name && this.namedDefine === true
-                                ? `        define(${libraryName(this.name)}, [], ${amdFactory});`
-                                : `        define([], ${amdFactory});`
-                        )
+                                    ? `        define(${libraryName(this.name)}, [], ${amdFactory});`
+                                    : `        define([], ${amdFactory});`
+                            )
                     ) +
                     (this.name
                         ? `
@@ -167,8 +167,8 @@ class UmdMainTemplatePlugin {
                         : `
     else {
 ${(externals.length > 0
-                        ? `        var a = typeof exports === "object" ? factory(${externalsRequireArray('commonjs')}) : factory(${externalsRootArray(externals)});`
-                        : '        var a = factory();')}
+                            ? `        var a = typeof exports === "object" ? factory(${externalsRequireArray('commonjs')}) : factory(${externalsRootArray(externals)});`
+                            : '        var a = factory();')}
         for(var i in a) (typeof exports === "object" ? exports : root)[i] = a[i];
     }
 `)
diff --git a/lib/WebpackOptionsApply.ts b/lib/WebpackOptionsApply.ts
index 7ad6b8a8e18..35fcff45a5c 100644
--- a/lib/WebpackOptionsApply.ts
+++ b/lib/WebpackOptionsApply.ts
@@ -24,6 +24,7 @@ import LoaderPlugin = require('./dependencies/LoaderPlugin');
 import CommonJsPlugin = require('./dependencies/CommonJsPlugin');
 import HarmonyModulesPlugin = require('./dependencies/HarmonyModulesPlugin');
 import SystemPlugin = require('./dependencies/SystemPlugin');
+import ImportPlugin = require('./dependencies/ImportPlugin');
 import AMDPlugin = require('./dependencies/AMDPlugin');
 import RequireContextPlugin = require('./dependencies/RequireContextPlugin');
 import RequireEnsurePlugin = require('./dependencies/RequireEnsurePlugin');
@@ -36,6 +37,7 @@ import FlagIncludedChunksPlugin = require('./optimize/FlagIncludedChunksPlugin')
 import OccurrenceOrderPlugin = require('./optimize/OccurrenceOrderPlugin');
 import FlagDependencyUsagePlugin = require('./FlagDependencyUsagePlugin');
 import FlagDependencyExportsPlugin = require('./FlagDependencyExportsPlugin');
+import EmittedAssetSizeLimitPlugin = require('./performance/EmittedAssetSizeLimitPlugin');
 import { ResolverFactory } from 'enhanced-resolve'
 import { WebpackOptions } from '../typings/webpack-types'
 import Compiler = require('./Compiler')
@@ -209,10 +211,10 @@ class WebpackOptionsApply extends OptionsApply {
             let comment = legacy && modern
                 ? '\n/*\n//@ sourceMappingURL=[url]\n//# sourceMappingURL=[url]\n*/'
                 : legacy
-                ? '\n/*\n//@ sourceMappingURL=[url]\n*/'
-                : modern
-                ? '\n//# sourceMappingURL=[url]'
-                : undefined;
+                    ? '\n/*\n//@ sourceMappingURL=[url]\n*/'
+                    : modern
+                        ? '\n//# sourceMappingURL=[url]'
+                        : undefined;
             const Plugin = evalWrapped ? EvalSourceMapDevToolPlugin : SourceMapDevToolPlugin;
             compiler.apply(
                 new Plugin(
@@ -235,10 +237,10 @@ class WebpackOptionsApply extends OptionsApply {
             let comment = legacy && modern
                 ? '\n//@ sourceURL=[url]\n//# sourceURL=[url]'
                 : legacy
-                ? '\n//@ sourceURL=[url]'
-                : modern
-                ? '\n//# sourceURL=[url]'
-                : undefined;
+                    ? '\n//@ sourceURL=[url]'
+                    : modern
+                        ? '\n//# sourceURL=[url]'
+                        : undefined;
             compiler.apply(new EvalDevToolModulePlugin(comment, options.output.devtoolModuleFilenameTemplate));
         }
 
@@ -259,6 +261,7 @@ class WebpackOptionsApply extends OptionsApply {
             new AMDPlugin(options.module, options.amd || {}),
             new CommonJsPlugin(options.module),
             new HarmonyModulesPlugin(),
+            new ImportPlugin(options.module),
             new SystemPlugin(options.module)
         );
 
@@ -273,13 +276,15 @@ class WebpackOptionsApply extends OptionsApply {
             new FlagDependencyUsagePlugin()
         );
 
+        compiler.apply(new EmittedAssetSizeLimitPlugin(options.performance));
+
         compiler.apply(new TemplatedPathPlugin());
 
         compiler.apply(new RecordIdsPlugin());
 
         compiler.apply(new WarnCaseSensitiveModulesPlugin());
 
-        if (options.cache === undefined ? options.watch : options.cache) {
+        if (options.cache) {
             const CachePlugin = require('./CachePlugin');
             compiler.apply(new CachePlugin(typeof options.cache === 'object' ? options.cache : undefined));
         }
diff --git a/lib/WebpackOptionsDefaulter.ts b/lib/WebpackOptionsDefaulter.ts
index 36d026089f7..1b4071fb3e9 100644
--- a/lib/WebpackOptionsDefaulter.ts
+++ b/lib/WebpackOptionsDefaulter.ts
@@ -71,6 +71,13 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
         this.set('node.__filename', 'mock');
         this.set('node.__dirname', 'mock');
 
+        this.set('performance.maxAssetSize', 250000);
+        this.set('performance.maxInitialChunkSize', 250000);
+        this.set('performance.errorOnHint', false);
+        this.set('performance.hints', 'make', function (options: WebpackOptions) {
+            return options.target === 'web';
+        });
+
         this.set('resolve', {});
         this.set('resolve.unsafeCache', true);
         this.set('resolve.modules', ['node_modules']);
diff --git a/lib/dependencies/ContextDependencyTemplateAsRequireCall.ts b/lib/dependencies/ContextDependencyTemplateAsRequireCall.ts
index d34bbb347ef..be46eae006c 100644
--- a/lib/dependencies/ContextDependencyTemplateAsRequireCall.ts
+++ b/lib/dependencies/ContextDependencyTemplateAsRequireCall.ts
@@ -6,7 +6,7 @@ import AMDRequireContextDependency = require('./AMDRequireContextDependency')
 import { ReplaceSource } from 'webpack-sources'
 import { WebpackOutputOptions } from '../../typings/webpack-types'
 import RequestShortener = require('../RequestShortener')
-import SystemImportContextDependency = require('./SystemImportContextDependency')
+import SystemImportContextDependency = require('./ImportContextDependency')
 import CommonJsRequireContextDependency = require('./CommonJsRequireContextDependency')
 
 type RequireContextDependency = AMDRequireContextDependency | SystemImportContextDependency | CommonJsRequireContextDependency
diff --git a/lib/dependencies/HarmonyCompatiblilityDependency.ts b/lib/dependencies/HarmonyCompatiblilityDependency.ts
new file mode 100644
index 00000000000..250a4063fc3
--- /dev/null
+++ b/lib/dependencies/HarmonyCompatiblilityDependency.ts
@@ -0,0 +1,33 @@
+/*
+ MIT License http://www.opensource.org/licenses/mit-license.php
+ Author Tobias Koppers @sokra
+ */
+import NullDependency = require('./NullDependency');
+import Module = require('../Module')
+import { ReplaceSource } from 'webpack-sources'
+
+class Template {
+    apply(
+        dep: HarmonyCompatiblilityDependency,
+        source: ReplaceSource,
+    ) {
+        const usedExports = dep.originModule.usedExports;
+        if (usedExports && !Array.isArray(usedExports)) {
+            const content = 'Object.defineProperty(exports, "__esModule", { value: true });\n';
+            source.insert(-1, content);
+        }
+
+    }
+}
+
+class HarmonyCompatiblilityDependency extends NullDependency {
+    constructor(public originModule: Module) {
+        super();
+    }
+
+    static Template = Template
+}
+
+HarmonyCompatiblilityDependency.prototype.type = 'harmony export header';
+
+export = HarmonyCompatiblilityDependency;
diff --git a/lib/dependencies/HarmonyExportDependencyParserPlugin.ts b/lib/dependencies/HarmonyExportDependencyParserPlugin.ts
index 95dd323087a..a1163825789 100644
--- a/lib/dependencies/HarmonyExportDependencyParserPlugin.ts
+++ b/lib/dependencies/HarmonyExportDependencyParserPlugin.ts
@@ -9,16 +9,27 @@ import HarmonyExportSpecifierDependency = require('./HarmonyExportSpecifierDepen
 import HarmonyExportImportedSpecifierDependency = require('./HarmonyExportImportedSpecifierDependency');
 import HarmonyImportDependency = require('./HarmonyImportDependency');
 import HarmonyModulesHelpers = require('./HarmonyModulesHelpers');
-import { Statement, ExportNamedDeclaration, ExportDefaultDeclaration, Expression, Node } from 'estree'
+import { Statement, ExportNamedDeclaration, ExportDefaultDeclaration, Expression, Node, SourceLocation } from 'estree'
 import Parser = require('../Parser')
+import HarmonyCompatiblilityDependency = require('./HarmonyCompatiblilityDependency')
+import Module = require('../Module')
+
+function makeHarmonyModule(module: Module, loc: SourceLocation) {
+    if (!module.meta.harmonyModule) {
+        const dep = new HarmonyCompatiblilityDependency(module);
+        dep.loc = loc;
+        module.addDependency(dep);
+        module.meta.harmonyModule = true;
+        module.strict = true;
+    }
+}
 
 export = AbstractPlugin.create({
     'export'(this: Parser, statement: ExportNamedDeclaration | ExportDefaultDeclaration) {
         const dep = new HarmonyExportHeaderDependency(statement.declaration && statement.declaration.range, statement.range);
         dep.loc = statement.loc;
         this.state.current.addDependency(dep);
-        this.state.module.meta.harmonyModule = true;
-        this.state.module.strict = true;
+        makeHarmonyModule(this.state.module, statement.loc);
         return true;
     },
     'export import'(this: Parser, statement: Statement, source: string) {
@@ -27,8 +38,7 @@ export = AbstractPlugin.create({
         this.state.current.addDependency(dep);
         // todo: typo
         this.state.lastHarmoryImport = dep;
-        this.state.module.meta.harmonyModule = true;
-        this.state.module.strict = true;
+        makeHarmonyModule(this.state.module, statement.loc);
         return true;
     },
     'export expression'(this: Parser, statement: Statement, expr: Expression) {
@@ -48,7 +58,7 @@ export = AbstractPlugin.create({
         let dep;
         if (rename === 'imported var') {
             const settings = this.state.harmonySpecifier[`$${id}`];
-            dep = new HarmonyExportImportedSpecifierDependency(this.state.module, settings[0], settings[1], settings[2], name, statement.range[1]);
+            dep = new HarmonyExportImportedSpecifierDependency(this.state.module, settings[0], settings[1], settings[2], name);
         }
         else {
             const immutable = statement.declaration && isImmutableStatement(statement.declaration);
@@ -63,7 +73,7 @@ export = AbstractPlugin.create({
     },
     'export import specifier'(this: Parser, statement: Statement, source: string, id: string, name: string) {
         // todo: here has typo
-        const dep = new HarmonyExportImportedSpecifierDependency(this.state.module, this.state.lastHarmoryImport, HarmonyModulesHelpers.getModuleVar(this.state, source), id, name, 0);
+        const dep = new HarmonyExportImportedSpecifierDependency(this.state.module, this.state.lastHarmoryImport, HarmonyModulesHelpers.getModuleVar(this.state, source), id, name);
         dep.loc = statement.loc;
         this.state.current.addDependency(dep);
         return true;
diff --git a/lib/dependencies/HarmonyExportImportedSpecifierDependency.ts b/lib/dependencies/HarmonyExportImportedSpecifierDependency.ts
index f6e96159eec..126193c3e1a 100644
--- a/lib/dependencies/HarmonyExportImportedSpecifierDependency.ts
+++ b/lib/dependencies/HarmonyExportImportedSpecifierDependency.ts
@@ -51,7 +51,7 @@ class Template {
         }
         else if (Array.isArray(dep.originModule.usedExports)) {
             // we know which exports are used
-            activeExports = HarmonyModulesHelpers.getActiveExports(dep.originModule);
+            activeExports = HarmonyModulesHelpers.getActiveExports(dep.originModule, dep);
             items = dep.originModule.usedExports.map(id => {
                 if (id === 'default') {
                     return;
@@ -77,7 +77,7 @@ class Template {
         }
         else if (dep.originModule.usedExports && importedModule && Array.isArray(importedModule.providedExports)) {
             // not sure which exports are used, but we know which are provided
-            activeExports = HarmonyModulesHelpers.getActiveExports(dep.originModule);
+            activeExports = HarmonyModulesHelpers.getActiveExports(dep.originModule, dep);
             items = importedModule.providedExports.map(id => {
                 if (id === 'default') {
                     return;
@@ -101,7 +101,7 @@ class Template {
         }
         else if (dep.originModule.usedExports) {
             // not sure which exports are used and provided
-            activeExports = HarmonyModulesHelpers.getActiveExports(dep.originModule);
+            activeExports = HarmonyModulesHelpers.getActiveExports(dep.originModule, dep);
             content = `/* harmony namespace reexport (unknown) */ for(var __WEBPACK_IMPORT_KEY__ in ${name}) `;
 
             // Filter out exports which are defined by other exports
@@ -117,7 +117,7 @@ class Template {
         else {
             content = '/* unused harmony reexport namespace */\n';
         }
-        source.insert(dep.position, content);
+        source.insert(-1, content);
     }
 }
 
@@ -127,8 +127,7 @@ class HarmonyExportImportedSpecifierDependency extends NullDependency {
         public importDependency: Dependency,
         public importedVar: string,
         public id: string,
-        public name: string,
-        public position: number
+        public name: string
     ) {
         super();
     }
@@ -148,7 +147,7 @@ class HarmonyExportImportedSpecifierDependency extends NullDependency {
             const providedExports = m.providedExports
             if (Array.isArray(this.originModule.usedExports)) {
                 // reexport * with known used exports
-                const activeExports = HarmonyModulesHelpers.getActiveExports(this.originModule);
+                const activeExports = HarmonyModulesHelpers.getActiveExports(this.originModule, this);
                 if (Array.isArray(providedExports)) {
                     return {
                         module: m,
@@ -232,6 +231,14 @@ class HarmonyExportImportedSpecifierDependency extends NullDependency {
     }
 
     describeHarmonyExport() {
+        const importedModule = this.importDependency.module;
+        if (!this.name && importedModule && Array.isArray(importedModule.providedExports)) {
+            // for a star export and when we know which exports are provided, we can tell so
+            return {
+                exportedName: importedModule.providedExports,
+                precedence: 3
+            }
+        }
         return {
             exportedName: this.name,
             precedence: this.name ? 2 : 3
diff --git a/lib/dependencies/HarmonyModulesHelpers.ts b/lib/dependencies/HarmonyModulesHelpers.ts
index ea1f0622f85..6eba1fc2d33 100644
--- a/lib/dependencies/HarmonyModulesHelpers.ts
+++ b/lib/dependencies/HarmonyModulesHelpers.ts
@@ -36,7 +36,7 @@ export function checkModuleVar(state: ParserState, request: string) {
     return getModuleVar(state, request);
 }
 
-// checks if an harmory dependency is active in a module according to
+// checks if an harmony dependency is active in a module according to
 // precedence rules.
 export function isActive(module: Module, depInQuestion: HarmonyExportDependency) {
     const desc = depInQuestion.describeHarmonyExport();
@@ -73,12 +73,17 @@ type HarmonyExportDependency = HarmonyExportSpecifierDependency | HarmonyExportI
 
 // get a list of named exports defined in a module
 // doesn't include * reexports.
-export function getActiveExports(module: Module): string[] {
-    // todo: there is no activeExports assignment at all across the repo
-    if (module.activeExports) {
-        return module.activeExports;
-    }
-    return module.dependencies.reduce(function (arr, dep: HarmonyExportDependency) {
+export function getActiveExports(module: Module, currentDependency: HarmonyExportDependency): string[] {
+    const desc = currentDependency && currentDependency.describeHarmonyExport();
+    const currentIndex = currentDependency ? module.dependencies.indexOf(currentDependency) : -1;
+
+    return module.dependencies.map(function (dep: HarmonyExportDependency, idx) {
+        return {
+            dep: dep,
+            idx: idx
+        }
+    }).reduce(function (arr, data) {
+        const dep = data.dep;
         if (!dep.describeHarmonyExport) {
             return arr;
         }
@@ -86,11 +91,17 @@ export function getActiveExports(module: Module): string[] {
         if (!d) {
             return arr;
         }
-        const name = d.exportedName;
-        if (!name || arr.includes(name)) {
-            return arr;
+        if (!desc
+            || (d.precedence < desc.precedence)
+            || (d.precedence === desc.precedence && data.idx < currentIndex)
+        ) {
+            const names = [].concat(d.exportedName);
+            names.forEach(function (name) {
+                if (name && arr.indexOf(name) < 0) {
+                    arr.push(name);
+                }
+            });
         }
-        arr.push(name);
         return arr;
     }, []);
 }
diff --git a/lib/dependencies/HarmonyModulesPlugin.ts b/lib/dependencies/HarmonyModulesPlugin.ts
index 7e91abcc12c..e477c77f39b 100644
--- a/lib/dependencies/HarmonyModulesPlugin.ts
+++ b/lib/dependencies/HarmonyModulesPlugin.ts
@@ -17,6 +17,7 @@ import Compiler = require('../Compiler')
 import Compilation = require('../Compilation')
 import Parser = require('../Parser')
 import { CompilationParams, ParserOptions } from '../../typings/webpack-types'
+import HarmonyCompatiblilityDependency = require('./HarmonyCompatiblilityDependency')
 
 class HarmonyModulesPlugin {
     apply(compiler: Compiler) {
@@ -29,6 +30,10 @@ class HarmonyModulesPlugin {
             compilation.dependencyFactories.set(HarmonyImportSpecifierDependency, new NullFactory());
             compilation.dependencyTemplates.set(HarmonyImportSpecifierDependency, new HarmonyImportSpecifierDependency.Template());
 
+            compilation.dependencyFactories.set(HarmonyCompatiblilityDependency, new NullFactory());
+            compilation.dependencyTemplates.set(HarmonyCompatiblilityDependency, new HarmonyCompatiblilityDependency.Template());
+
+
             compilation.dependencyFactories.set(HarmonyExportHeaderDependency, new NullFactory());
             compilation.dependencyTemplates.set(HarmonyExportHeaderDependency, new HarmonyExportHeaderDependency.Template());
 
diff --git a/lib/dependencies/SystemImportContextDependency.ts b/lib/dependencies/ImportContextDependency.ts
similarity index 82%
rename from lib/dependencies/SystemImportContextDependency.ts
rename to lib/dependencies/ImportContextDependency.ts
index 21d1db444a1..09a64041963 100644
--- a/lib/dependencies/SystemImportContextDependency.ts
+++ b/lib/dependencies/ImportContextDependency.ts
@@ -6,7 +6,7 @@ import ContextDependency = require('./ContextDependency');
 import CriticalDependencyWarning = require('./CriticalDependencyWarning');
 import { SourceRange } from '../../typings/webpack-types'
 
-class SystemImportContextDependency extends ContextDependency {
+class ImportContextDependency extends ContextDependency {
     async: boolean
     critical: false | string
 
@@ -30,6 +30,6 @@ class SystemImportContextDependency extends ContextDependency {
     static Template = require('./ContextDependencyTemplateAsRequireCall')
 }
 
-SystemImportContextDependency.prototype.type = 'System.import context';
+ImportContextDependency.prototype.type = 'System.import context';
 
-export = SystemImportContextDependency;
+export = ImportContextDependency;
diff --git a/lib/dependencies/SystemImportDependenciesBlock.ts b/lib/dependencies/ImportDependenciesBlock.ts
similarity index 67%
rename from lib/dependencies/SystemImportDependenciesBlock.ts
rename to lib/dependencies/ImportDependenciesBlock.ts
index 2858cbba2c7..201e96dd2fc 100644
--- a/lib/dependencies/SystemImportDependenciesBlock.ts
+++ b/lib/dependencies/ImportDependenciesBlock.ts
@@ -3,18 +3,18 @@
  Author Tobias Koppers @sokra
  */
 import AsyncDependenciesBlock = require('../AsyncDependenciesBlock');
-import SystemImportDependency = require('./SystemImportDependency');
+import ImportDependency = require('./ImportDependency');
 import { SourceRange } from '../../typings/webpack-types'
 import { SourceLocation } from 'estree'
 import Module = require('../Module')
 
-class SystemImportDependenciesBlock extends AsyncDependenciesBlock {
+class ImportDependenciesBlock extends AsyncDependenciesBlock {
     constructor(request: string, public range: SourceRange, module: Module, loc: SourceLocation) {
         super(null, module, loc);
-        const dep = new SystemImportDependency(request, this);
+        const dep = new ImportDependency(request, this);
         dep.loc = loc;
         this.addDependency(dep);
     }
 }
 
-export = SystemImportDependenciesBlock;
+export = ImportDependenciesBlock;
diff --git a/lib/dependencies/SystemImportDependency.ts b/lib/dependencies/ImportDependency.ts
similarity index 78%
rename from lib/dependencies/SystemImportDependency.ts
rename to lib/dependencies/ImportDependency.ts
index 8fae25e7ebc..9ec6af81bec 100644
--- a/lib/dependencies/SystemImportDependency.ts
+++ b/lib/dependencies/ImportDependency.ts
@@ -8,17 +8,17 @@ import WebpackMissingModule = require('./WebpackMissingModule');
 import RequestShortener = require('../RequestShortener')
 import { WebpackOutputOptions } from '../../typings/webpack-types'
 import { ReplaceSource } from 'webpack-sources'
-import SystemImportDependenciesBlock = require('./SystemImportDependenciesBlock')
+import ImportDependenciesBlock = require('./ImportDependenciesBlock')
 
 class Template {
     apply(
-        dep: SystemImportDependency,
+        dep: ImportDependency,
         source: ReplaceSource,
         outputOptions: WebpackOutputOptions,
         requestShortener: RequestShortener
     ) {
         const depBlock = dep.block;
-        const promise = DepBlockHelpers.getDepBlockPromise(depBlock, outputOptions, requestShortener, 'System.import');
+        const promise = DepBlockHelpers.getDepBlockPromise(depBlock, outputOptions, requestShortener, 'import()');
         let comment = '';
         if (outputOptions.pathinfo) {
             comment = `/*! ${requestShortener.shorten(dep.request)} */ `;
@@ -35,14 +35,14 @@ class Template {
     }
 }
 
-class SystemImportDependency extends ModuleDependency {
-    constructor(request: string, public block: SystemImportDependenciesBlock) {
+class ImportDependency extends ModuleDependency {
+    constructor(request: string, public block: ImportDependenciesBlock) {
         super(request);
     }
 
     static Template = Template
 }
 
-SystemImportDependency.prototype.type = 'System.import';
+ImportDependency.prototype.type = 'import()';
 
-export = SystemImportDependency;
+export = ImportDependency;
diff --git a/lib/dependencies/SystemImportParserPlugin.ts b/lib/dependencies/ImportParserPlugin.ts
similarity index 63%
rename from lib/dependencies/SystemImportParserPlugin.ts
rename to lib/dependencies/ImportParserPlugin.ts
index 06560f3b0a6..8801e1e63a5 100644
--- a/lib/dependencies/SystemImportParserPlugin.ts
+++ b/lib/dependencies/ImportParserPlugin.ts
@@ -2,32 +2,32 @@
  MIT License http://www.opensource.org/licenses/mit-license.php
  Author Tobias Koppers @sokra
  */
-import SystemImportContextDependency = require('./SystemImportContextDependency');
-import SystemImportDependenciesBlock = require('./SystemImportDependenciesBlock');
+import ImportContextDependency = require('./ImportContextDependency');
+import ImportDependenciesBlock = require('./ImportDependenciesBlock');
 import ContextDependencyHelpers = require('./ContextDependencyHelpers');
 import Parser = require('../Parser')
 import { CallExpression } from 'estree'
 import { ModuleOptions } from '../../typings/webpack-types'
 
-class SystemImportParserPlugin {
+class ImportParserPlugin {
     constructor(public options: ModuleOptions) {
     }
 
     apply(parser: Parser) {
         const options = this.options;
-        parser.plugin('call System.import', function (expr: CallExpression) {
+        parser.plugin(['call System.import', 'import-call'], function (expr: CallExpression) {
             if (expr.arguments.length !== 1) {
-                throw new Error('Incorrect number of arguments provided to \'System.import(module: string) -> Promise\'.');
+                throw new Error('Incorrect number of arguments provided to \'import(module: string) -> Promise\'.');
             }
             let dep;
             const param = this.evaluateExpression(expr.arguments[0]);
             if (param.isString()) {
-                const depBlock = new SystemImportDependenciesBlock(param.string, expr.range, this.state.module, expr.loc);
+                const depBlock = new ImportDependenciesBlock(param.string, expr.range, this.state.module, expr.loc);
                 this.state.current.addBlock(depBlock);
                 return true;
             }
             else {
-                dep = ContextDependencyHelpers.create(SystemImportContextDependency, expr.range, param, expr, options);
+                dep = ContextDependencyHelpers.create(ImportContextDependency, expr.range, param, expr, options);
                 if (!dep) {
                     return;
                 }
@@ -40,4 +40,4 @@ class SystemImportParserPlugin {
     }
 }
 
-export = SystemImportParserPlugin;
+export = ImportParserPlugin;
diff --git a/lib/dependencies/ImportPlugin.ts b/lib/dependencies/ImportPlugin.ts
new file mode 100644
index 00000000000..2177b56afc3
--- /dev/null
+++ b/lib/dependencies/ImportPlugin.ts
@@ -0,0 +1,44 @@
+/*
+ MIT License http://www.opensource.org/licenses/mit-license.php
+ Author Tobias Koppers @sokra
+ */
+import ImportDependency = require('./ImportDependency');
+import ImportContextDependency = require('./ImportContextDependency');
+import UnsupportedFeatureWarning = require('../UnsupportedFeatureWarning');
+import ConstDependency = require('./ConstDependency');
+import BasicEvaluatedExpression = require('../BasicEvaluatedExpression');
+import ImportParserPlugin = require('./ImportParserPlugin');
+import Compiler = require('../Compiler')
+import Compilation = require('../Compilation')
+import { CompilationParams, ParserOptions, ModuleOptions } from '../../typings/webpack-types'
+import Parser = require('../Parser')
+
+class ImportPlugin {
+    constructor(public options: ModuleOptions) {
+    }
+
+    apply(compiler: Compiler) {
+        const options = this.options;
+        compiler.plugin('compilation', (compilation: Compilation, params: CompilationParams) => {
+            const normalModuleFactory = params.normalModuleFactory;
+            const contextModuleFactory = params.contextModuleFactory;
+
+            compilation.dependencyFactories.set(ImportDependency, normalModuleFactory);
+            compilation.dependencyTemplates.set(ImportDependency, new ImportDependency.Template());
+
+            compilation.dependencyFactories.set(ImportContextDependency, contextModuleFactory);
+            compilation.dependencyTemplates.set(ImportContextDependency, new ImportContextDependency.Template());
+
+            params.normalModuleFactory.plugin('parser', (parser: Parser, parserOptions: ParserOptions) => {
+
+                if (typeof parserOptions.import !== 'undefined' && !parserOptions.import) {
+                    return;
+                }
+
+                parser.apply(new ImportParserPlugin(options));
+            });
+        });
+    }
+}
+
+export = ImportPlugin;
diff --git a/lib/dependencies/SystemPlugin.ts b/lib/dependencies/SystemPlugin.ts
index b19afdf2eb3..55347822c57 100644
--- a/lib/dependencies/SystemPlugin.ts
+++ b/lib/dependencies/SystemPlugin.ts
@@ -2,12 +2,9 @@
  MIT License http://www.opensource.org/licenses/mit-license.php
  Author Tobias Koppers @sokra
  */
-import SystemImportDependency = require('./SystemImportDependency');
-import SystemImportContextDependency = require('./SystemImportContextDependency');
 import UnsupportedFeatureWarning = require('../UnsupportedFeatureWarning');
 import ConstDependency = require('./ConstDependency');
 import BasicEvaluatedExpression = require('../BasicEvaluatedExpression');
-import SystemImportParserPlugin = require('./SystemImportParserPlugin');
 import Compiler = require('../Compiler')
 import Compilation = require('../Compilation')
 import Parser = require('../Parser')
@@ -23,12 +20,6 @@ class SystemPlugin {
             const normalModuleFactory = params.normalModuleFactory;
             const contextModuleFactory = params.contextModuleFactory;
 
-            compilation.dependencyFactories.set(SystemImportDependency, normalModuleFactory);
-            compilation.dependencyTemplates.set(SystemImportDependency, new SystemImportDependency.Template());
-
-            compilation.dependencyFactories.set(SystemImportContextDependency, contextModuleFactory);
-            compilation.dependencyTemplates.set(SystemImportContextDependency, new SystemImportContextDependency.Template());
-
             params.normalModuleFactory.plugin('parser', function (parser: Parser, parserOptions: ParserOptions) {
                 if (typeof parserOptions.system !== 'undefined' && !parserOptions.system) {
                     return;
@@ -73,7 +64,6 @@ class SystemPlugin {
                     this.state.current.addDependency(dep);
                     return true;
                 });
-                parser.apply(new SystemImportParserPlugin(options));
             });
         });
     }
diff --git a/lib/node/NodeOutputFileSystem.ts b/lib/node/NodeOutputFileSystem.ts
index 4569c8253c3..37ac42b21d2 100644
--- a/lib/node/NodeOutputFileSystem.ts
+++ b/lib/node/NodeOutputFileSystem.ts
@@ -23,8 +23,14 @@ interface NodeOutputFileSystem {
     rmdir(path: string | Buffer, callback?: (err?: NodeJS.ErrnoException) => void): void;
     unlink(path: string | Buffer, callback?: (err?: NodeJS.ErrnoException) => void): void;
     writeFile(filename: string, data: any, callback?: (err: NodeJS.ErrnoException) => void): void;
-    writeFile(filename: string, data: any, options: { encoding?: string; mode?: number; flag?: string; }, callback?: (err: NodeJS.ErrnoException) => void): void;
-    writeFile(filename: string, data: any, options: { encoding?: string; mode?: string; flag?: string; }, callback?: (err: NodeJS.ErrnoException) => void): void;
+    writeFile(
+        filename: string, data: any, options: { encoding?: string; mode?: number; flag?: string; },
+        callback?: (err: NodeJS.ErrnoException) => void
+    ): void;
+    writeFile(
+        filename: string, data: any, options: { encoding?: string; mode?: string; flag?: string; },
+        callback?: (err: NodeJS.ErrnoException) => void
+    ): void;
     join(...paths: string[]): string;
 }
 
diff --git a/lib/node/NodeWatchFileSystem.ts b/lib/node/NodeWatchFileSystem.ts
index 6330ff32190..12907a24dd9 100644
--- a/lib/node/NodeWatchFileSystem.ts
+++ b/lib/node/NodeWatchFileSystem.ts
@@ -4,7 +4,6 @@
  */
 import Watchpack = require('watchpack');
 import { WatchOptions, ErrCallback, AbstractInputFileSystem } from '../../typings/webpack-types'
-import * as Resolve from 'enhanced-resolve'
 
 class NodeWatchFileSystem {
     watcherOptions: {
diff --git a/lib/optimize/CommonsChunkPlugin.ts b/lib/optimize/CommonsChunkPlugin.ts
index c9834f78d3b..96935bc8792 100644
--- a/lib/optimize/CommonsChunkPlugin.ts
+++ b/lib/optimize/CommonsChunkPlugin.ts
@@ -33,6 +33,8 @@ The available options are:
     names: string[]
     filename: string
     minChunks: number
+    chunks: string[]
+    children: boolean
     async: boolean
     minSize: number
 `);
@@ -59,7 +61,7 @@ The available options are:
         const filenameTemplate = this.filenameTemplate;
         const minChunks = this.minChunks;
         const selectedChunks = this.selectedChunks;
-        const async = this.async;
+        const asyncOption = this.async;
         const minSize = this.minSize;
         const ident = this.ident;
         compiler.plugin('this-compilation', function (compilation: Compilation) {
@@ -71,7 +73,7 @@ The available options are:
                 compilation[ident] = true;
 
                 let commonChunks: Chunk[];
-                if (!chunkNames && (selectedChunks === false || async)) {
+                if (!chunkNames && (selectedChunks === false || asyncOption)) {
                     commonChunks = chunks;
                 }
                 else if (Array.isArray(chunkNames) || typeof chunkNames === 'string') {
@@ -96,9 +98,9 @@ The available options are:
                             return selectedChunks.includes(chunk.name);
                         });
                     }
-                    else if (selectedChunks === false || async) {
+                    else if (selectedChunks === false || asyncOption) {
                         usedChunks = (commonChunk.chunks || []).filter(chunk => // we can only move modules from this chunk if the "commonChunk" is the only parent
-                        async || chunk.parents.length === 1);
+                        asyncOption || chunk.parents.length === 1);
                     }
                     else {
                         if (commonChunk.parents.length > 0) {
@@ -114,8 +116,8 @@ The available options are:
                         });
                     }
                     let asyncChunk: Chunk
-                    if (async) {
-                        asyncChunk = this.addChunk(typeof async === 'string' ? async : undefined);
+                    if (asyncOption) {
+                        asyncChunk = this.addChunk(typeof asyncOption === 'string' ? asyncOption : undefined);
                         asyncChunk.chunkReason = 'async commons chunk';
                         asyncChunk.extraAsync = true;
                         asyncChunk.addParent(commonChunk);
@@ -170,7 +172,7 @@ The available options are:
                         commonChunk.addModule(module);
                         module.addChunk(commonChunk);
                     });
-                    if (async) {
+                    if (asyncOption) {
                         reallyUsedChunks.forEach(chunk => {
                             if (chunk.isInitial()) {
                                 return;
diff --git a/lib/performance/AssetsOverSizeLimitWarning.ts b/lib/performance/AssetsOverSizeLimitWarning.ts
new file mode 100644
index 00000000000..f0271eb3c34
--- /dev/null
+++ b/lib/performance/AssetsOverSizeLimitWarning.ts
@@ -0,0 +1,31 @@
+/*
+ MIT License http://www.opensource.org/licenses/mit-license.php
+ Author Sean Larkin @thelarkinn
+ */
+import SizeFormatHelpers = require('../SizeFormatHelpers');
+
+class AssetsOverSizeLimitWarning extends Error {
+    assets: AssetsOverSizeLimitWarning.OverSizeLimit[]
+
+    constructor(assetsOverSizeLimit: AssetsOverSizeLimitWarning.OverSizeLimit[], assetLimit: number) {
+        super();
+        Error.captureStackTrace(this, AssetsOverSizeLimitWarning);
+        this.name = 'AssetsOverSizeLimitWarning';
+        this.assets = assetsOverSizeLimit;
+
+        const assetLists = this.assets.map(asset => `\n  ${asset.name} (${SizeFormatHelpers.formatSize(asset.size)})`)
+            .join('');
+
+        this.message = `asset size limit: The following asset(s) exceed the recommended size limit (${SizeFormatHelpers.formatSize(assetLimit)}). \nThis can impact web performance.\nAssets: ${assetLists}`;
+    }
+}
+
+declare namespace AssetsOverSizeLimitWarning {
+    interface OverSizeLimit {
+        name: string
+        size: number
+        isOverSizeLimit?: boolean
+    }
+}
+
+export = AssetsOverSizeLimitWarning;
diff --git a/lib/performance/EmittedAssetSizeLimitPlugin.ts b/lib/performance/EmittedAssetSizeLimitPlugin.ts
new file mode 100644
index 00000000000..809ac1e216a
--- /dev/null
+++ b/lib/performance/EmittedAssetSizeLimitPlugin.ts
@@ -0,0 +1,95 @@
+/*
+ MIT License http://www.opensource.org/licenses/mit-license.php
+ Author Sean Larkin @thelarkinn
+ */
+import path = require('path');
+
+import EntrypointsOverSizeLimitWarning = require('./EntrypointsOverSizeLimitWarning');
+import AssetsOverSizeLimitWarning = require('./AssetsOverSizeLimitWarning');
+import NoAsyncChunksWarning = require('./NoAsyncChunksWarning');
+import Compiler = require('../Compiler')
+import Compilation = require('../Compilation')
+import { PerformanceOptions } from '../../typings/webpack-types'
+
+class EmittedAssetSizeLimitPlugin {
+    maxAssetSize?: number
+    maxInitialSize?: number
+    hints?
+    errorOnHint?: boolean
+
+    constructor(performanceOptions: PerformanceOptions) {
+        this.maxAssetSize = performanceOptions.maxAssetSize;
+        this.maxInitialSize = performanceOptions.maxInitialChunkSize;
+        this.hints = performanceOptions.hints;
+        this.errorOnHint = performanceOptions.errorOnHint;
+    }
+
+    apply(compiler: Compiler) {
+        if (!this.hints) {
+            return;
+        }
+        const entrypointSizeLimit = this.maxInitialSize;
+        const sizeLimit = this.maxAssetSize;
+        const hints = this.hints;
+        const shouldErrorOnHint = this.errorOnHint;
+
+        compiler.plugin('after-emit', (compilation: Compilation, callback) => {
+            const warnings = [];
+
+            const assetsOverSizeLimit: AssetsOverSizeLimitWarning.OverSizeLimit[] = [];
+
+            Object.keys(compilation.assets).forEach(asset => {
+                const obj = {
+                    name: asset,
+                    size: compilation.assets[asset].size()
+                } as AssetsOverSizeLimitWarning.OverSizeLimit;
+
+                if (doesExceedLimit(sizeLimit, obj.size)) {
+                    obj.isOverSizeLimit = true;
+                    assetsOverSizeLimit.push(obj);
+                    compilation.assets[asset].isOverSizeLimit = true;
+                }
+            });
+
+            const hasAsyncChunks = compilation.chunks.filter(chunk => !chunk.isInitial()).length > 0;
+
+            const entrypointsOverLimit = Object.keys(compilation.entrypoints)
+                .map(key => compilation.entrypoints[key])
+                .filter(entry => doesExceedLimit(entrypointSizeLimit, entry.getSize(compilation)));
+
+            // 1. Individual Chunk: Size < 250kb
+            // 2. Collective Initial Chunks [entrypoint] (Each Set?): Size < 250kb
+            // 3. No Async Chunks
+            // if !1, then 2, if !2 return
+            if (assetsOverSizeLimit.length > 0) {
+                warnings.push(new AssetsOverSizeLimitWarning(assetsOverSizeLimit, sizeLimit));
+            }
+            if (entrypointsOverLimit.length > 0) {
+                warnings.push(new EntrypointsOverSizeLimitWarning(entrypointsOverLimit, compilation, entrypointSizeLimit));
+            }
+
+            if (warnings.length > 0) {
+                if (!hasAsyncChunks) {
+                    warnings.push(new NoAsyncChunksWarning());
+                }
+
+                if (shouldErrorOnHint) {
+                    Array.prototype.push.apply(compilation.errors, warnings);
+                }
+                else {
+                    Array.prototype.push.apply(compilation.warnings, warnings);
+                }
+            }
+
+            callback();
+        });
+    }
+}
+
+export = EmittedAssetSizeLimitPlugin;
+
+// When using this we should always
+// compare byte size and then format later
+function doesExceedLimit(limit: number, actualSize: number) {
+    return limit < actualSize;
+}
diff --git a/lib/performance/EntrypointsOverSizeLimitWarning.ts b/lib/performance/EntrypointsOverSizeLimitWarning.ts
new file mode 100644
index 00000000000..8953168d32a
--- /dev/null
+++ b/lib/performance/EntrypointsOverSizeLimitWarning.ts
@@ -0,0 +1,27 @@
+/*
+ MIT License http://www.opensource.org/licenses/mit-license.php
+ Author Sean Larkin @thelarkinn
+ */
+import SizeFormatHelpers = require('../SizeFormatHelpers');
+import Compilation = require('../Compilation')
+import Entrypoint = require('../Entrypoint')
+
+class EntrypointsOverSizeLimitWarning extends Error {
+    constructor(public entrypoints: Entrypoint[], compilation: Compilation, entrypointLimit: number) {
+        super();
+        Error.captureStackTrace(this, EntrypointsOverSizeLimitWarning);
+        this.name = 'EntrypointsOverSizeLimitWarning';
+
+        const entrypointCompilation = compilation;
+        const entrypointList = this.entrypoints.map(entrypoint =>
+                `\n  ${entrypoint.name} (${SizeFormatHelpers.formatSize(entrypoint.getSize(entrypointCompilation))})\n${entrypoint.getFiles()
+                    .map((filename, index) => '      ' + entrypoint.getFiles()[index] + '\n')
+                    .join('')}`
+            )
+            .join('');
+
+        this.message = `entrypoint size limit: The following entrypoint(s) combined asset size exceeds the recommended limit (${SizeFormatHelpers.formatSize(entrypointLimit)}). This can impact web performance.\nEntrypoints:${entrypointList}`;
+    }
+}
+
+export = EntrypointsOverSizeLimitWarning;
diff --git a/lib/performance/NoAsyncChunksWarning.ts b/lib/performance/NoAsyncChunksWarning.ts
new file mode 100644
index 00000000000..822f9c9cab7
--- /dev/null
+++ b/lib/performance/NoAsyncChunksWarning.ts
@@ -0,0 +1,15 @@
+/*
+ MIT License http://www.opensource.org/licenses/mit-license.php
+ Author Sean Larkin @thelarkinn
+ */
+class NoAsyncChunksWarning extends Error {
+    constructor() {
+        super();
+        Error.captureStackTrace(this, NoAsyncChunksWarning);
+        this.name = 'NoAsyncChunksWarning';
+
+        this.message = 'webpack performance recommendations: \n' + 'You can limit the size of your bundles by using System.import() or require.ensure to lazy load some parts of your application.\n' + 'For more info visit https://webpack.js.org/guides/code-splitting/';
+    }
+}
+
+export = NoAsyncChunksWarning;
diff --git a/tsconfig.json b/tsconfig.json
index de773842390..9c3d1ce8246 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -11,7 +11,7 @@
     ],
     "declaration": false,
     "noImplicitAny": true,
-    "noImplicitThis": true,
+    "noImplicitThis": false,
     "suppressImplicitAnyIndexErrors": true,
     "pretty": true,
     "noImplicitReturns": false,
diff --git a/typings/webpack-types.d.ts b/typings/webpack-types.d.ts
index 6dfa24f4649..4b42d5cddc6 100644
--- a/typings/webpack-types.d.ts
+++ b/typings/webpack-types.d.ts
@@ -173,6 +173,7 @@ declare interface StatsOptions {
     modulesSort?: string;
     // Add public path information
     publicPath?: boolean;
+    performance?: boolean;
     providedExports?: boolean;
     // Add information about the reasons why modules are included
     reasons: boolean;
@@ -240,6 +241,13 @@ declare interface FilenameTemplateInfo {
     shortIdentifier: string;
 }
 
+declare interface PerformanceOptions {
+    maxAssetSize?: number
+    maxInitialChunkSize?: number
+    hints?
+    errorOnHint?: boolean
+}
+
 declare interface WebpackOptions {
     /** Set the value of require.amd and define.amd. */
     amd?: { [moduleName: string]: boolean };
@@ -272,6 +280,7 @@ declare interface WebpackOptions {
     plugins?: Tapable.Plugin;
     /** Capture timing information for each module. */
     profile?: boolean;
+    performance?: PerformanceOptions;
     /** Used for recordsInputPath and recordsOutputPath */
     recordsPath?: string;
     /** Load compiler state from a json file. */
@@ -472,6 +481,7 @@ declare interface ParserOptions {
     requireJs: boolean;
     node: false | NodeOption;
     ident: string
+    import: boolean
 }
 
 declare interface WatchFileSystem {