var Permission = require('auth-permission')
  , Role = require('auth-role')
  , Scope = require('auth-scope');

// Specify any number of roles or permissions
var roles = new Scope([
  Role('api')
    .allow(Permission('read profile'))
    .allow(Permission('read post')),
  Permission('create account'),
  Permission('update billing')
]);

// Create scope from available roles and/or permissions
var scope = new Scope(roles.find(['api', 'create account']));

// Get scope permissions
var permissions = scope.permissions();

JSON.stringify(permissions);
// => ['read profile', 'read post', 'create account']