diff --git a/onoff/onoff.d.ts b/onoff/onoff.d.ts
new file mode 100644
index 000000000..7e92ebc21
--- /dev/null
+++ b/onoff/onoff.d.ts
@@ -0,0 +1,55 @@
+// Type definitions for onoff
+// Project: https://github.com/fivdi/onoff
+// Definitions by: Marcel Ernst <https://github.com/marcel-ernst>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+/// <reference path="../node/node.d.ts" />
+
+declare namespace __ONOFF {
+
+    var version:string;
+
+    interface GpioOptions {
+        debounceTimeout:number;
+    }
+
+    class Gpio {
+        constructor(gpio:number, direction:string);
+        constructor(gpio:number, direction:string, edge:string);
+        constructor(gpio:number, direction:string, edge:string, options:GpioOptions);
+        constructor(gpio:number, direction:string, options:GpioOptions);
+
+        gpio:number
+        gpioPath:string;
+        opts:GpioOptions;
+        readBuffer:Buffer;
+        listeners:Array<(error:Error, value:number) => void>;
+        valueFd:number;
+
+        read(cb:(err:Error, value:number) => void):void;
+        readSync():boolean; // maybe number?
+
+        write(value:number, cb:(err:Error, value:number) => void):void;
+        writeSync(value:number):void; // maybe number?
+
+        watch(cb:(error:Error, value:number) => void):void;
+        unwatch():void;
+        unwatch(cb:(error:Error, value:number) => void):void;
+        unwatchAll():void;
+
+        direction():string;
+        setDirection(value:string);
+
+        edge():string;
+        setEdge(value:string):void;
+
+        options():GpioOptions;
+
+        unexport():void;
+    }
+
+}
+
+declare module "onoff" {
+    export = __ONOFF;
+}
\ No newline at end of file