Documentation

Everything you need to run Coldtill on your own server and connect a shop to it.

Accept your first payment

API key, payment, checkout, webhook: the whole flow in fifteen minutes.

Self-hosting guide

Choosing a server, locking down the dashboard, backups, updates and a go-live checklist.

Domains and a private dashboard

DNS and Cloudflare, signing in over Tailscale, and several projects with their own domains.

API reference

Every merchant endpoint and webhook, generated from the OpenAPI 3.1 spec.

Security model

Why the server that takes orders can't spend the money it receives.

Build it with a coding agent

A ready prompt for Claude Code, Codex or Cursor, and Markdown copies of every page.

Build it with a coding agent

Copy this prompt into your project. It links the docs as Markdown, so the agent reads the real API before it writes any code. Paste into Claude Code, Codex, Cursor or your favourite coding agent.

I want to accept crypto payments in my shop with Coldtill, a self-hosted crypto payment gateway.
Read these docs before writing any code:

- [Guide: accept a payment](https://coldtill.com/docs/guides/accept-payments.md)
- [Merchant API](https://coldtill.com/docs/api.md)
- [Webhooks](https://coldtill.com/docs/webhooks.md)
- [OpenAPI specification](https://coldtill.com/openapi.yaml)
- [All Coldtill docs](https://coldtill.com/llms.txt)

Then look at my codebase and add Coldtill as a payment option:
1. Create a payment with POST /api/v1/payment when the customer checks out, and redirect them to the checkout URL it returns.
2. Add a webhook endpoint that verifies the X-Coldtill-Signature-V2 header and the timestamp, then marks the order paid on payment.filled or payment.over_filled.
3. Read the Coldtill URL, API key and webhook secret from environment variables. Never hard-code them.
4. Explain what you changed and how I can test it with a small payment.

Every docs page also has a Copy page as Markdown button. For the whole set, give your agent llms.txt (an index with a link to every page) or llms-full.txt (every page in one file), or the OpenAPI specification.