Node.js with FB Flow

gistfile1.js

// @flow weak
/* jshint ignore:start */
declare module 'http' {
  declare function createServer(callback: (req: httpIncomingMessage, res: httpServerResponse) => void): httpServer
}

// declare class http {
//   createServer(callback: (req: httpIncomingMessage, res: httpServerResponse) => void): httpServer
// }

declare class httpServer {

}

declare class httpIncomingMessage {

}

declare class httpServerResponse {

}
/* jshint ignore:end */

require('http')

/* OUTPUT:
$ flow

~/Dropbox/playground/flowtype/hello.js:24:1,15: http
Required module not found

...
*/