{
  "name": "peerchat",
  "description": "Chat in P2P",
  "version": "1.0.0",
  "main": "server.js",
  "scripts": {
    "start": "node server.js"
  },
  "keywords": [],
  "author": {
    "name": "Matthieu Corageoud",
    "email": "matthieu.corageoud@gmail.com"
  },
  "license": "Unlicense",
  "repository": {
    "type": "git",
    "url": "https://github.com/matco/peerchat.git"
  },
  "bugs": {
    "url": "https://github.com/matco/peerchat/issues"
  },
  "dependencies": {
    "node-static": "^0.7.9",
    "ws": "^2.2.0"
  }
}

{
  "name": "peerchat",
  "description": "Chat in P2P",
  "version": "1.0.0",
  "main": "server.js",
  "scripts": {
    "start": "node server.js"
  },
  "keywords": [],
  "author": {
    "name": "Matthieu Corageoud",
    "email": "matthieu.corageoud@gmail.com"
  },
  "license": "Unlicense",
  "repository": {
    "type": "git",
    "url": "https://github.com/matco/peerchat.git"
  },
  "bugs": {
    "url": "https://github.com/matco/peerchat/issues"
  },
  "dependencies": {
    "node-static": "^0.7.9",
    "ws": "^2.2.0"
  },
  "engines" : {
     "node" : "7.x"
  }
}

Add engine in NPM description file
Add engine in NPM description file
