I remember the time when I was a part of the team to provide our web-based applications as service (SaaS). We had ideas, of course, based on our previous experience in the web development area. But it was really difficult to start.
This time the situation is changed. Many web apps are SaaS-based now. And you can find not just short posts about SaaS but the articles for long reading. One of these is The SaaS Handbook – How to Build Your First Software-as-a-Service Product Step-By-Step.
The article describes a tech stack (it’s JS – Node.js + Preact – an alternative version of the React), structure, design, integrations with third-party services, and deploy and gives tips and ideas to build your version of the SaaS..