This document summarizes lessons learned from converting a web application to a multitenant architecture and deploying it on Amazon Web Services using Scalarium. Key lessons included implementing a "shared nothing" database architecture, automating machine installation and management with Chef recipes, using multiple availability zones for high availability, choosing a NoSQL database like CouchDB for scalability, implementing stringent security practices like IAM and MFA, and considering human factors like data privacy when moving to a cloud platform. The speaker concluded it is important to automate everything possible and not forget the human aspects of transitioning to SaaS.