npm install @billium/node

import { Billium } from '@billium/node';

const billium = new Billium({
  apiKey: process.env.BILLIUM_API_KEY,
  merchantId: process.env.BILLIUM_MERCHANT_ID,
  webhookSecret: process.env.BILLIUM_WEBHOOK_SECRET,
});

const invoice = await billium.invoices.create(
  { name: 'Order #1234', rawAmount: 99.99 },
  { idempotencyKey: crypto.randomUUID() },
);

.
├── packages/
│   ├── node/              # @billium/node — TypeScript Node.js SDK
│   │   ├── src/           # Source
│   │   ├── tests/         # Vitest test suite
│   │   ├── README.md      # Public-facing docs (rendered on npmjs.com)
│   │   └── CHANGELOG.md   # Per-release notes
│   └── mcp/               # @billium/mcp — Model Context Protocol server
│       ├── src/           # Server + tool definitions
│       ├── tests/         # Vitest in-memory round-trip suite
│       └── README.md      # Host setup (Claude Code, Cursor, …)
└── .github/
    ├── workflows/         # CI + release automation
    ├── ISSUE_TEMPLATE/    # Bug + feature request forms
    └── CODEOWNERS         # Review requirements

npm install        # installs all workspace packages
npm run lint       # typechecks every package (src + tests)
npm test           # runs every package's test suite
npm run build      # builds every package