# Documentation

Start with the task you want to complete. These guides describe **v0.1.0-beta.3**,
including the PayIn checkout and reference-payer readiness. Use the documentation
at the beta.2 tag when operating that older release.

## Try, integrate and operate

| Task | Guide |
| --- | --- |
| Evaluate without funds | [Local demo](DEMO.md) |
| Understand incoming payments | [PayIn](PAYIN.md) |
| Implement a compatible payer | [Payment Request v1](PAYMENT-REQUEST.md) |
| Start a real receiver | [Merchant quickstart](QUICKSTART.md) |
| Integrate an application | [Merchant integration](MERCHANT-INTEGRATION.md), [runnable example](../examples/README.md) |
| Pay from a separate host | [Payer integration](PAYER-INTEGRATION.md) |
| Deploy and maintain | [Deployment](DEPLOYMENT.md), [production runbook](PRODUCTION-RUNBOOK.md) |
| Resolve errors | [Troubleshooting](TROUBLESHOOTING.md) |
| Understand commands | [CLI reference](CLI.md) |
| Understand configuration | [Configuration](CONFIGURATION.md) |
| Build against the API | [HTTP reference](API.md), [OpenAPI](openapi.json) |
| Interpret payment state | [Payment states](PAYMENT-STATES.md) |
| Test usability independently | [Usability study protocol](USABILITY-TESTING.md) |

## Architecture and security

[Product boundary](PRODUCT-MODEL.md), [architecture](ARCHITECTURE.md),
[operator security](SECURITY.md), [threat model](THREAT-MODEL.md) and
[vulnerability reporting](../SECURITY.md).

## Historical verification and controlled pilots

The following are technical evidence and maintainer procedures, not installation
prerequisites. Their dates and tested versions matter.

- [Operational profile](OPERATIONAL-PROFILE.md)
- [Primitive gate](PRIMITIVE-GATE.md)
- [Mainnet gate](MAINNET-GATE.md) and [pilot procedure](PILOT-GUIDE.md)
- [Pilot observations](PILOT-FINDINGS.md)
- [Independent pilot](EXTERNAL-PILOT.md)
- [Maturity assessment](security/MATURITY-ASSESSMENT-2026-08-30.md)
- [Differential review](security/DIFFERENTIAL-REVIEW-2026-08-30.md)
- [Public evidence](../artifacts/)

Planning and grant material is kept under [archive](archive/README.md).
Future product scope is in the [roadmap](ROADMAP.md).