# Milestone 1 Completion Note

## Project

Open Solar Payments: Open-Source Bitcoin Payment Rails for Solar Access in Emerging Markets

## Milestone

Design and publish the open-source payment module architecture, API shape, and integration documentation.

## Status

Complete.

## Completion Summary

Milestone 1 establishes the public technical foundation for an open-source Bitcoin/Lightning payment module for solar commerce and installer settlement.

The work defines:

- The module boundary between open-source payment infrastructure and Suntecorb's private marketplace code.
- The architecture for payment requests, Lightning invoice generation, webhook processing, receipts, and installer settlement records.
- The initial API shape for merchant integration.
- The data model for payment requests, invoices, events, receipts, and settlements.
- The integration path for Suntecorb and other solar merchants.
- The reference implementation plan for testing the module in Suntecorb.

## Public Page

Live page:

https://suntecorb.one/open-solar-payments

## Documentation Package

- `README.md`: project overview and Milestone 1 scope
- `ARCHITECTURE.md`: module architecture and boundaries
- `API_SPEC.md`: initial endpoint and webhook specification
- `DATA_MODEL.md`: payment, invoice, receipt, and settlement schemas
- `INTEGRATION_GUIDE.md`: merchant integration flow
- `REFERENCE_IMPLEMENTATION_PLAN.md`: Suntecorb pilot plan
- `GRANT_READINESS_CHECKLIST.md`: Spiral grant-readiness audit

## Grant-Ready Claim

The project can now honestly say:

> Milestone 1 is complete. We have published the initial architecture, API shape, data model, integration guide, and Suntecorb reference implementation plan for an open-source Bitcoin/Lightning payment module for solar commerce and installer settlement.

## Next Milestone

Milestone 2 should implement the first working Bitcoin/Lightning checkout flow:

- Create payment request
- Generate Lightning invoice
- Track invoice status
- Process payment confirmation webhook
- Generate receipt
- Connect paid status back to a solar quote or order