buildout fails when installing gulp

[sureshvv]

Develop: '/home/suresh/repos/plone.app.angularjs/.'
Installing gulp.
module.js:338
throw err;
^
Error: Cannot find module 'del'
at Function.Module._resolveFilename (module.js:336:15)
at Function.Module._load (module.js:278:25)
at Module.require (module.js:365:17)
at require (module.js:384:17)
at Object. (/home/suresh/repos/plone.app.angularjs/gulpfile.js:2:11)
at Module._compile (module.js:460:26)
at Object.Module._extensions..js (module.js:478:10)
at Module.load (module.js:355:32)
at Function.Module._load (module.js:310:12)
at Module.require (module.js:365:17)
While:
Installing gulp.

An internal error occurred due to a bug in either zc.buildout or in a
recipe being used: