TL;DR: it's a guide with best practices for any engineer who builds & deploys SaaS, based on experience working and scaling many apps on Heroku platform. Introduction In the modern era, software is commonly delivered as a service: called web apps, or software-as-a-service. The twelve-factor app is a methodology for building software-as-a-service apps that: Use declarative formats for … Continue reading 12 factors of modern SaaS →