Build with Claude Code

LUMX_API_KEY=lumx_sk_sandbox_xxxxxxxxxxxxxxxx
LUMX_ENV=sandbox

.env
.env.local
.env*.local

- Lumx API calls only run server-side. Never reference
  `process.env.LUMX_API_KEY` from a file that ends up in the browser
  bundle.

claude mcp add --transport http lumx-docs https://docs.lumx.io/mcp

Add a stablecoin payments backend that uses the Lumx API. Lumx
connects local banking rails to stablecoins so I can collect, hold,
convert, and pay out money in either form.

Rules
- Read LUMX_API_KEY from environment variables (process.env in Node,
  os.environ in Python, ENV in Ruby, etc.). Never expose it in
  client-side code. Always call Lumx from server routes.
- Pick the base URL from LUMX_ENV. Default to
  https://api-sandbox.lumx.io. Use https://api.lumx.io when LUMX_ENV
  is "production".
- Send every request with the headers:
    Authorization: Bearer ${LUMX_API_KEY}
    Content-Type: application/json
- On non-2xx responses, surface the Lumx error body and HTTP status.
  Do not retry 4xx.

Before writing code
- Inspect the repo and write idiomatic code for the existing stack —
  reuse the existing router style, HTTP client, and error helper if
  one is already there. If the project is empty, ask me which stack
  before scaffolding.

Server routes to build
1. POST /api/customers — calls Lumx POST /customers. Body: type
   ("INDIVIDUAL" or "BUSINESS"), name, taxId, country (ISO-3), email.
   Returns the Lumx customer record including verification.link.
2. POST /api/on-ramp — calls Lumx POST /transactions/on-ramp. Body:
   customerId, currency (ISO-3), amount (string). Returns the
   rail-specific deposit instructions.
3. GET /api/transactions/:id — calls Lumx GET /transactions/:id and
   returns the transaction's current status and timeline.

UI to build
- Customer onboarding screen: form that calls POST /api/customers,
  then renders verification.link as a button.
- On-ramp deposit screen: form that picks a customer, sets a
  currency and amount, calls POST /api/on-ramp, then renders the
  returned deposit instructions.

After writing
- Run the app, hit each route once with curl in the terminal, and
  paste the responses back so I can confirm shape.

Reference: https://docs.lumx.io

const LUMX_BASE =
  process.env.LUMX_ENV === "production"
    ? "https://api.lumx.io"
    : "https://api-sandbox.lumx.io";

async function lumx(path: string, init?: RequestInit) {
  const res = await fetch(`${LUMX_BASE}${path}`, {
    ...init,
    headers: {
      Authorization: `Bearer ${process.env.LUMX_API_KEY}`,
      "Content-Type": "application/json",
      ...init?.headers,
    },
  });
  if (!res.ok) {
    throw new Error(`Lumx ${res.status}: ${await res.text()}`);
  }
  return res.json();
}

export const createCustomer = (input: {
  type: "INDIVIDUAL" | "BUSINESS";
  name: string;
  taxId: string;
  country: string;
  email: string;
}) => lumx("/customers", { method: "POST", body: JSON.stringify(input) });

export const createOnRamp = (input: {
  customerId: string;
  currency: string;
  amount: string;
}) =>
  lumx("/transactions/on-ramp", {
    method: "POST",
    body: JSON.stringify(input),
  });

export const getTransaction = (id: string) => lumx(`/transactions/${id}`);