Starting of Proxy server doesn't work

[primius]

When trying to start the proxy server with:
node --harmony index.js
im getting the following error message:

module.js:540
throw err;
^
Error: Cannot find module 'ffi'
at Function.Module._resolveFilename (module.js:538:15)
at Function.Module._load (module.js:468:25)
at Module.require (module.js:587:17)
at require (internal/module.js:11:18)
at Object. (D:\Eclipse-Workspace\iotaproxy\lib\ccurlprovider.js:11:13)
at Module._compile (module.js:643:30)
at Object.Module._extensions..js (module.js:654:10)
at Module.load (module.js:556:32)
at tryModuleLoad (module.js:499:12)
at Function.Module._load (module.js:491:3)

[primius]

It seems you have to install a module called 'ffi' in addition. It can be done with the following command:
npm install ffi

[nicoschtein]

ffi is a dependency, which is included in package.json
Instructions on REAMDE.md include a step npm install which should install all dependencies, in this case ffi.