Polybuild

gistfile1.txt

// Given this file tree
/utils/polybuild
/projects/my-app/
  components/
    polymer
    iron-icon
  elements.html
  index.html  

// Build use cases:

>utils/polybuild/bin/polybuild projects/my-app/index.html
// output: 
index.build.html
index.build.js

>utils/polybuild/bin/polybuild projects/my-app/elements.html
// output: 
elements.build.html
elements.build.js
// manual fixup of index.html required

// Build index.html with gulp:
(e.g.) gulpconfig.js:
polybuild = require('polybuild');
gulp = require('gulp');
gulp.task('build', function() {
  return gulp.src('index.html').pipe(polybuild()).pipe(gulp.dst('.'));
});