All output on stderr causes a 500 Internal Server Error: ``` javascript proc.stderr.pipe(concat(function error(err) { console.log(err); if (!err.length) return endLog() process.stderr.write(err.toString()) res.statusCode = 500 ``` This includes the `DeprecationWarning: 'GLOBAL' is deprecated, use 'global'` warning added in Node.js v6: https://github.com/nodejs/node/pull/1838, triggered by cwise-parser Works with beefy (no server error)