I built an AI-native SaaS starter kit for Next.js 16 — here's what I learned

Every time I start a new SaaS project, I spend the first 2-3 weeks on the same things: authentication, Stripe billing, email, a dashboard layout, and now — AI integration. The actual product doesn't get touched until week 3. So I built LaunchKit — a production-ready SaaS foundation that handles all of this out of the box. But this isn't just another boilerplate post. I want to share the specific architectural decisions and lessons learned, because some of them go against conventional wisdom. Why "AI-native" matters Most existing SaaS boilerplates (ShipFast, Supastarter, MakerKit) were built in 2023. If they have AI features at all, it's a basic chat page bolted on as an afterthought. In 2026, almost every new SaaS product has some AI component. The chat interface, streaming responses, conversation persistence, and plan-based usage limits shouldn't be something you wire up yourself — they should be part of the foundation. LaunchKit's AI chat is a first-class feature: // src/app/api/ai/c