Introduction

What this template is, what it is not, and who it is for.

This is a composable Next.js template built entirely on Once UI. It ships a marketing site, a product shell, a Supabase auth layer and this documentation engine — and a scaffolder that copies only the parts you ask for. The idea is narrow on purpose: instead of one large starter you strip down, you pick the surfaces you want and get an app that contains nothing else. A storefront composed without the auth slice has no Supabase code, no Supabase dependencies and no Supabase environment variables anywhere in the tree.

What you get

Once UI primitives only. No Tailwind, no CSS modules, no styled-components. Spacing and colour come from tokens.
A typed error contract. Every API route answers with the same { error: { code, message } } shape.
Graceful degradation. Missing cloud credentials disable cloud features; they never crash a build or a dev server.
Static-first docs and blog. MDX on the filesystem, rendered through registered Once UI components.

What it is not

It is not a design system, and it is not a CMS. Components live in @once-ui-system/core; this repository composes them. Content is MDX and plain JavaScript objects under src/content.