I built http://vat.landedcost.avalara.com/ http://vat.landedcost.avalara.com/ using this same architecture pattern. The site is served up via S3, and the back-

I built http://vat.landedcost.avalara.com/ http://vat.landedcost.avalara.com/ using this same architecture pattern. The site is served up via S3, and the back-end logic is a Lambda module that wraps a SOAP API.