diff --git a/enhanced-resolve/enhanced-resolve-tests.ts b/enhanced-resolve/enhanced-resolve-tests.ts
index d456872bfa..dfd5087be4 100644
--- a/enhanced-resolve/enhanced-resolve-tests.ts
+++ b/enhanced-resolve/enhanced-resolve-tests.ts
@@ -1,5 +1,5 @@
 import resolve = require('enhanced-resolve');
-import { ResolveResult } from 'enhanced-resolve/lib/common-types'
+import { ResolveResult, AbstractInputFileSystem } from 'enhanced-resolve/lib/common-types'
 import Resolver = require('enhanced-resolve/lib/Resolver')
 
 resolve('lib', 'string', function (err) { });
@@ -13,15 +13,12 @@ resolve(context, 'path', 'string', function () { });
 let resolver: Resolver
 resolver = resolve.ResolverFactory.createResolver({
     extensions: ['.js'],
-    fileSystem: {} as resolve.CachedInputFileSystem
+    fileSystem: {} as AbstractInputFileSystem
 });
 
 const nfs = new resolve.NodeJsInputFileSystem();
 
-const snfs = new resolve.SyncNodeJsInputFileSystem();
-
 const cfs = new resolve.CachedInputFileSystem(nfs, 4);
-const cfs2 = new resolve.CachedInputFileSystem(snfs, 4);
 
 let result: ResolveResult
 
diff --git a/enhanced-resolve/index.d.ts b/enhanced-resolve/index.d.ts
index 06ccd64604..d773f52b16 100644
--- a/enhanced-resolve/index.d.ts
+++ b/enhanced-resolve/index.d.ts
@@ -1,4 +1,4 @@
-// Type definitions for enhanced-resolve v2.3.0
+// Type definitions for enhanced-resolve v3.0.0
 // Project: http://github.com/webpack/enhanced-resolve.git
 // Definitions by: e-cloud <https://github.com/e-cloud>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
@@ -10,14 +10,13 @@ import fs = require('fs');
 import {
     ResolveResult,
     LoggingCallbackWrapper,
-    CommonFileSystemMethod,
     ResolverRequest,
     ResolveContext,
     AbstractInputFileSystem
 } from './lib/common-types'
 import { Dictionary } from './lib/concord'
 import Resolver = require('./lib/Resolver');
-import Tapable = require('tapable')
+import Tapable = require('tapable');
 
 declare namespace Resolve {
     function sync(path: string, request: string): ResolveResult;
@@ -66,6 +65,7 @@ declare namespace Resolve {
             resolveToContext?: boolean;
             symlinks?: string[] | boolean;
             unsafeCache?: boolean | Dictionary<any>;
+            useSyncFileSystemCalls?: boolean;
         }
         interface AliasItem {
             alias: string;
@@ -76,12 +76,9 @@ declare namespace Resolve {
     }
 
     class NodeJsInputFileSystem {
-        isSync(): boolean;
-
-        readdir(path: string, callback: (err: Error, files: string[]) => void): void;
-
         stat(path: string, callback?: (err: NodeJS.ErrnoException, stats: fs.Stats) => any): void;
 
+        readdir(path: string, callback: (err: Error, files: string[]) => void): void
         readFile(
             filename: string, encoding: string,
             callback: (err: NodeJS.ErrnoException, data: string) => void
@@ -100,32 +97,25 @@ declare namespace Resolve {
         readFile(filename: string, callback: (err: NodeJS.ErrnoException, data: Buffer) => void): void;
 
         readlink(path: string, callback?: (err: NodeJS.ErrnoException, linkString: string) => any): void;
-    }
 
-    class SyncNodeJsInputFileSystem {
-        isSync(): boolean;
+        statSync(path: string | Buffer): fs.Stats;
 
-        stat: CommonFileSystemMethod;
-        readdir: CommonFileSystemMethod;
+        readdirSync(path: string): string[];
 
-        readFile(
-            filename: string, encoding: string,
-            callback: (err: NodeJS.ErrnoException, data: string) => void
-        ): void;
-        readFile(
+        readFileSync(filename: string, encoding: string): string;
+        readFileSync(
             filename: string, options: {
                 encoding: string;
                 flag?: string;
-            }, callback: (err: NodeJS.ErrnoException, data: string) => void
-        ): void;
-        readFile(
-            filename: string, options: {
+            }
+        ): string;
+        readFileSync(
+            filename: string, options?: {
                 flag?: string;
-            }, callback: (err: NodeJS.ErrnoException, data: Buffer) => void
-        ): void;
-        readFile(filename: string, callback: (err: NodeJS.ErrnoException, data: Buffer) => void): void;
+            }
+        ): Buffer;
 
-        readlink: CommonFileSystemMethod;
+        readlinkSync(path: string | Buffer): string;
     }
 
     class CachedInputFileSystem {
@@ -133,19 +123,27 @@ declare namespace Resolve {
 
         constructor(fileSystem: AbstractInputFileSystem, duration: number);
 
-        isSync(): boolean;
+        stat?(path: string, callback: (err: NodeJS.ErrnoException, stats: fs.Stats) => void): void;
+
+        readdir?(path: string, callback: (err: NodeJS.ErrnoException, files: string[]) => void): void;
+
+        readFile?(path: string, callback: (err: NodeJS.ErrnoException, data: Buffer) => void): void;
+
+        readJson?(path: string, callback: (err: NodeJS.ErrnoException, data: any) => void): void;
+
+        readlink?(path: string, callback: (err: NodeJS.ErrnoException, linkString: string) => void): void;
+
+        statSync?(path: string | Buffer): fs.Stats;
+
+        readdirSync?(path: string): string[];
+
+        readFileSync?(filename: string, options?: { flag?: string; }): Buffer;
+
+        readlinkSync?(path: string | Buffer): string;
+
+        readJsonSync?(path: string): any;
 
         purge(what?: string | string[]): void;
-
-        readdir(path: string, callback: (err: NodeJS.ErrnoException, files: string[]) => void): void;
-
-        readFile(path: string, callback: (err: NodeJS.ErrnoException, data: Buffer) => void): void;
-
-        readJson(path: string, callback: (err: NodeJS.ErrnoException, data: any) => void): void;
-
-        readlink(path: string, callback: (err: NodeJS.ErrnoException, linkString: string) => void): void;
-
-        stat(path: string, callback: (err: NodeJS.ErrnoException, stats: fs.Stats) => void): void;
     }
 }
 
diff --git a/enhanced-resolve/lib/Storage.d.ts b/enhanced-resolve/lib/Storage.d.ts
index cc4790d200..b9512825fa 100644
--- a/enhanced-resolve/lib/Storage.d.ts
+++ b/enhanced-resolve/lib/Storage.d.ts
@@ -1,26 +1,29 @@
 /// <reference types="node" />
-import { CommonFileSystemMethod } from './common-types';
-import { Dictionary } from './concord';
-
+import { CommonFileSystemMethod } from './common-types'
+import { Dictionary } from './concord'
 declare class Storage {
-    duration: number;
-    running: Dictionary<Function[]>;
-    data: Dictionary<any>;
-    levels: string[][];
     count: number;
+    data: Dictionary<any>;
+    duration: number;
     interval: NodeJS.Timer | null;
+    levels: string[][];
     needTickCheck: boolean;
     nextTick: number | null;
     passive: boolean;
+    running: Dictionary<Function[]>;
 
     constructor(duration: number);
 
     ensureTick(): void;
 
-    finished(name: string): void;
+    finished(name: string, err: NodeJS.ErrnoException | null, result: any): void;
+
+    finishedSync(name: string, err: NodeJS.ErrnoException | null, result?: any): void;
 
     provide(name: string, provider: CommonFileSystemMethod, callback: (...args: any[]) => any): any;
 
+    provideSync(name: string, provider: (name: string) => any): any;
+
     tick(): true | undefined;
 
     checkTicks(): void;
diff --git a/enhanced-resolve/lib/SyncAsyncFileSystemDecorator.d.ts b/enhanced-resolve/lib/SyncAsyncFileSystemDecorator.d.ts
new file mode 100644
index 0000000000..f7956dcead
--- /dev/null
+++ b/enhanced-resolve/lib/SyncAsyncFileSystemDecorator.d.ts
@@ -0,0 +1,21 @@
+/// <reference types="node" />
+import fs = require('fs');
+import { AbstractInputFileSystem } from './common-types';
+
+declare class SyncAsyncFileSystemDecorator {
+    fs: AbstractInputFileSystem;
+
+    readdir?(path: string, callback: (err: NodeJS.ErrnoException | null, files?: string[]) => void): void;
+
+    readFile?(filename: string, callback: (err: NodeJS.ErrnoException | null, data?: Buffer) => void): void;
+
+    readJson?(path: string, callback: (err: NodeJS.ErrnoException | null, data?: any) => void): void;
+
+    readlink?(path: string, callback: (err: NodeJS.ErrnoException | null, linkString?: string) => void): void;
+
+    stat?(path: string, callback: (err: NodeJS.ErrnoException | null, stats?: fs.Stats) => void): void;
+
+    constructor(fs: AbstractInputFileSystem);
+}
+
+export = SyncAsyncFileSystemDecorator;
diff --git a/enhanced-resolve/lib/common-types.d.ts b/enhanced-resolve/lib/common-types.d.ts
index ff764ad67d..6607dee64f 100644
--- a/enhanced-resolve/lib/common-types.d.ts
+++ b/enhanced-resolve/lib/common-types.d.ts
@@ -39,6 +39,9 @@ export interface ResolverRequest {
     query?: string;
     relativePath?: string;
     request: string;
+    __innerRequest?: string;
+    __innerRequest_request?: string;
+    __innerRequest_relativePath?: string;
 }
 
 export interface LoggingCallbackTools {
@@ -58,13 +61,29 @@ export interface ErrorCallback<T> {
 }
 
 export interface AbstractInputFileSystem {
-    isSync(): boolean;
     purge?(what?: string | string[]): void;
     readdir(path: string, callback: (err: NodeJS.ErrnoException, files: string[]) => void): void;
+    readdirSync?(path: string): string[];
+    readFile(filename: string, encoding: string, callback: (err: NodeJS.ErrnoException, data: string) => void): void;
+    readFile(
+        filename: string, options: {
+            encoding: string;
+            flag?: string;
+        }, callback: (err: NodeJS.ErrnoException, data: string) => void
+    ): void;
+    readFile(
+        filename: string, options: {
+            flag?: string;
+        }, callback: (err: NodeJS.ErrnoException, data: Buffer) => void
+    ): void;
     readFile(filename: string, callback: (err: NodeJS.ErrnoException, data: Buffer) => void): void;
+    readFileSync?(filename: string): Buffer;
     readJson?(path: string, callback: (err: NodeJS.ErrnoException, data: any) => void): void;
+    readJsonSync?(path: string): any;
     readlink(path: string, callback: (err: NodeJS.ErrnoException, linkString: string) => void): void;
+    readlinkSync?(path: string): string;
     stat(path: string, callback: (err: NodeJS.ErrnoException, stats: fs.Stats) => void): void;
+    statSync?(path: string): fs.Stats;
 }
 
 export interface CommonFileSystemMethod {