An MVP can be a form. A SaaS is a product many companies rent. How I would design tenancy, subscriptions, onboarding, and ops - and what I would not copy from big platforms in year one.
A practical playbook: what an MVP is (and is not), the five filters I use to pick technology, a default 2026 web stack, and what I refuse to add before the first real users.
Vibe coding is building software by describing intent in natural language and iterating on what the AI produces. Here is what it is, when it works, when it fails, and how to use it without shipping a mess.