old_contents: 'use strict'
  
  let path = require('path')
  
  let runCommand = require('./run-command')
  let isThere = require('is-there')
  
  let buildCommand = (arr) => arr.join(' && ')
  
  // Don't run gulp if there isn't a Gulpfile.
  if (!isThere(path.join(__dirname, '../Gulpfile.js'))) {
    process.exit()
  }
  
  if (process.env.LE_SERF_PRODUCTION) {
    runCommand(buildCommand([
      'bower prune',
      'bower install',
      'gulp clear',
      'gulp build'
    ]))
  } else if (process.env.HAS_JOSH_K_SEAL_OF_APPROVAL) {
    // Don't build anything on Travis.
    process.exit()
  } else {
    runCommand(buildCommand([
      'bower prune',
      'bower install',
      'gulp clear'
    ]))
  }
  
new_contents: 'use strict'
  
  let path = require('path')
  
  let runCommand = require('./run-command')
  let isThere = require('is-there')
  
  let buildCommand = (arr) => arr.join(' && ')
  
  // Don't run gulp if there isn't a Gulpfile.
  if (!isThere(path.join(__dirname, '../Gulpfile.js'))) {
    process.exit()
  }
  
  if (process.env.LE_SERF_PRODUCTION) {
    runCommand(buildCommand([
      'bower prune',
      'bower install',
      'gulp clear',
      'gulp build'
    ]))
  } else if (process.env.TRAVIS && process.env.CI) {
    // Don't build anything on Travis.
    process.exit()
  } else {
    runCommand(buildCommand([
      'bower prune',
      'bower install',
      'gulp clear'
    ]))
  }
  
subject: Make postinstall script a little clearer.