Migration to a static site: Experience with Metalsmith vs Gulp

I started this site using poet on top of node.js and express, mainly wanting to expand my node skills and use my free Azure credits I got as a Microsoft employee. Azure Websites, the Heroku-like PaaS had just launched (now called App Services). It was a nice experience.

Later on while working at Appuri, we decided to move our public website off of Hubspot as it was a nightmare for our talented designer, Jeff Reynolds, who knew HTML and CSS, to work in. It would need marketing functionality, but we took the approach that whatever we needed could be provided via a 3rd party JavaScript tag on the client. So we didn't need a server at all. We could simply serve it from an S3 bucket cheaply and it will always be up. Circle CI would build the site and sync the bucket.

So how to build it?