The agent-ready SaaS starter for TanStack Start
VAT handled, ship in a weekend. Auth, billing, database patterns, and the CLAUDE.md conventions your coding agent needs — all in one repo.
What's inside
Every feature listed here is already implemented in the codebase you receive.
TanStack Start
SSR, type-safe file-based routing, and server functions out of the box.
Supabase auth
Email + password, password reset, and a reusable route guard for protected pages.
Profiles + RLS pattern
Auto-created profile rows and a documented Row-Level Security template you copy for every new table.
Polar billing (MoR)
Merchant-of-record checkout — EU/UK VAT and US sales tax handled without extra code.
shadcn/ui design system
Inter, neutral zinc palette, indigo accent, and a working light / dark theme toggle.
Agent-ready docs
A CLAUDE.md that teaches Claude Code and Cursor your conventions so they extend the code correctly.
How it works
Three steps from checkout to shipping.
- 01
Buy once
One payment via Polar. VAT and invoice handled.
- 02
Instant access
Connect GitHub in your Polar portal and get invited to the private repo — usually under a minute.
- 03
Ship your SaaS
Clone, rename, deploy. Focus on your product, not the plumbing.
Documentation your agent can read
CLAUDE.md documents folder structure, naming rules, the RLS pattern, and step-by-step conventions. Point Claude Code or Cursor at the repo and it extends the codebase the same way you would.
Sample convention from CLAUDE.md:
## How to add a protected route
1. Create `src/routes/_authenticated/<name>.tsx`.
2. Export `createFileRoute("/_authenticated/<name>")`.
The URL is `/<name>` — the `_authenticated`
segment is stripped from the path.
3. No auth code needed — the `_authenticated`
layout gates every child route via `beforeLoad`.