diff --git a/types/isstream/index.d.ts b/types/isstream/index.d.ts
index b3d581e781..2dd8731df1 100644
--- a/types/isstream/index.d.ts
+++ b/types/isstream/index.d.ts
@@ -1,19 +1,39 @@
 // Type definitions for isstream 0.1
 // Project: https://github.com/rvagg/isstream
-// Definitions by: Claas Ahlrichs <https://github.com/claasahl>
+// Definitions by: My Self <https://github.com/me>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 
-/// <reference types="node" />
-
 export = isstream;
 
-declare function isstream(obj: any): boolean;
+declare function isstream(obj: any): any;
 
 declare namespace isstream {
-    function isDuplex(obj: any): boolean;
+    const prototype: {
+    };
 
-    function isReadable(obj: any): boolean;
+    function isDuplex(obj: any): any;
+
+    function isReadable(obj: any): any;
+
+    function isWritable(obj: any): any;
+
+    namespace isDuplex {
+        const prototype: {
+        };
+
+    }
+
+    namespace isReadable {
+        const prototype: {
+        };
+
+    }
+
+    namespace isWritable {
+        const prototype: {
+        };
+
+    }
 
-    function isWritable(obj: any): boolean;
 }
 
diff --git a/types/isstream/isstream-tests.ts b/types/isstream/isstream-tests.ts
index 107f1d46eb..e69de29bb2 100644
--- a/types/isstream/isstream-tests.ts
+++ b/types/isstream/isstream-tests.ts
@@ -1,37 +0,0 @@
-import isStream, {isReadable, isWritable, isDuplex} from 'isstream';
-import * as Stream from 'stream';
- 
-isStream(new Stream()) // true
- 
-isStream({}) // false
- 
-isStream(new Stream.Readable())    // true
-isStream(new Stream.Writable())    // true
-isStream(new Stream.Duplex())      // true
-isStream(new Stream.Transform())   // true
-isStream(new Stream.PassThrough()) // true
-
-
-
- 
-isReadable(new Stream()) // false
-isWritable(new Stream()) // false
-isDuplex(new Stream())   // false
- 
-isReadable(new Stream.Readable())    // true
-isReadable(new Stream.Writable())    // false
-isReadable(new Stream.Duplex())      // true
-isReadable(new Stream.Transform())   // true
-isReadable(new Stream.PassThrough()) // true
- 
-isWritable(new Stream.Readable())    // false
-isWritable(new Stream.Writable())    // true
-isWritable(new Stream.Duplex())      // true
-isWritable(new Stream.Transform())   // true
-isWritable(new Stream.PassThrough()) // true
- 
-isDuplex(new Stream.Readable())    // false
-isDuplex(new Stream.Writable())    // false
-isDuplex(new Stream.Duplex())      // true
-isDuplex(new Stream.Transform())   // true
-isDuplex(new Stream.PassThrough()) // true
\ No newline at end of file
diff --git a/types/isstream/tsconfig.json b/types/isstream/tsconfig.json
index 223c0a8c00..ddea72dd3e 100644
--- a/types/isstream/tsconfig.json
+++ b/types/isstream/tsconfig.json
@@ -7,15 +7,13 @@
         "noImplicitAny": true,
         "noImplicitThis": true,
         "strictNullChecks": true,
-        "strictFunctionTypes": true,
         "baseUrl": "../",
         "typeRoots": [
             "../"
         ],
         "types": [],
         "noEmit": true,
-        "forceConsistentCasingInFileNames": true,
-        "esModuleInterop": true
+        "forceConsistentCasingInFileNames": true
     },
     "files": [
         "index.d.ts",