I built <a href="http:&#x2F;&#x2F;vat.landedcost.avalara.com&#x2F;" rel="nofollow">http:&#x2F;&#x2F;vat.landedcost.avalara.com&#x2F;</a> using this same architecture pattern.<p>The site is served up via S3, and the back-end logic is a Lambda module that wraps a SOAP API.