SvelteKit recipe

OpenReceive ships no SvelteKit package. A SvelteKit endpoint (+server.ts) takes a Web-standard Request and returns a Response, and so does @openreceive/http, so the integration is the route below. Your server code creates each Lightning invoice, the payment goes straight to your wallet, and payment attempts are stored in your app’s database. There is no OpenReceive account and no background worker.

Optional swaps let customers pay with USDT, USDC, SOL, and ETH. A swap provider you configure converts the payment to BTC over Lightning, and it settles into the same wallet. Available assets and networks depend on the provider.

This recipe was checked with @sveltejs/kit 3.0, @sveltejs/adapter-node 6.0 and @openreceive/* 0.4.25. The built app ran on Node in Docker, with Postgres and a test wallet on a public NWC relay. In Chromium, the buyer’s checkout page showed the Lightning invoice. A stranger got 403 from the payment routes and 404 from the page, and a request that named its own amount got 400. When the wallet marked the invoice paid, the page showed it paid and onPaid marked the order paid.

npm install @openreceive/http @openreceive/svelte pg

Where it runs

On Node, with @sveltejs/adapter-node. The wallet connection and your database driver need Node, so the route cannot run on an edge runtime. The Vercel and Netlify adapters deploy Node functions: read Bitcoin checkout on serverless hosts first. For Cloudflare Workers, the TanStack Start recipe explains what a Worker needs. This recipe was not run on those hosts.

Secrets

SvelteKit 3 reads the environment variables you declare in src/env.ts. The build runs your app to analyse it, without your secrets, so require them only when the app starts:

// src/env.ts
import { building } from "$app/env";
import { defineEnvVars } from "@sveltejs/kit/env";

const secret = (value: string | undefined): string => {
  if (value) return value;
  if (building) return "";
  throw new Error("is not set");
};

export const variables = defineEnvVars({
  NWC_URI: { schema: secret, description: "Receive-only NWC code from your wallet" },
  DATABASE_URL: { schema: secret, description: "Postgres connection string" },
});

Never mark them public: true, which would send them to the browser.

The payment route

Keep the handler under src/lib/server/. SvelteKit refuses to bundle a module from there into browser code:

// src/lib/server/openreceive.ts
import { createStack, type Stack } from "@openreceive/http";
import type { RequestEvent } from "@sveltejs/kit";
import { NWC_URI } from "$app/env/private";
import { db } from "./db"; // your existing pg Pool
import { findOrder } from "./orders"; // your own orders

let stack: Stack | undefined;

// Built on the first request, not at import: the build imports server
// modules to analyse them, and a stack connects to the wallet at once.
function openReceive(): Stack {
  stack ??= createStack({
    wallet: { nwc: NWC_URI },
    storage: {
      db,
      // Runs once, inside the transaction that records the payment.
      onPaid: async ({ reference, paidAt, query }) => {
        await query(
          "UPDATE orders SET state = 'paid', paid_at = $1 WHERE id = $2 AND state = 'awaiting_payment'",
          [paidAt, reference],
        );
      },
    },
    // The price comes from the order row, never from the request.
    amountFor: async (reference) => {
      const order = await findOrder(reference);
      return order?.state === "awaiting_payment"
        ? { currency: order.currency, value: order.amount, description: order.title }
        : null;
    },
    // Only the buyer may pay for their order.
    authorize: async ({ native, resource }) => {
      const event = native as RequestEvent;
      const order = resource.reference ? await findOrder(resource.reference) : undefined;
      return Boolean(order && order.visitor === event.cookies.get("visitor"));
    },
    // adapter-node's client address: the socket, or ADDRESS_HEADER behind a proxy.
    rateLimiting: {
      ip: ({ native }) => (native as RequestEvent).getClientAddress(),
    },
  });
  return stack;
}

export function handleOpenReceive(event: RequestEvent): Promise<Response> {
  return openReceive().handler(event.request, { native: event });
}

// src/routes/openreceive/[...path]/+server.ts — every route under /openreceive/
import { handleOpenReceive } from "#lib/server/openreceive.ts";
import type { RequestHandler } from "./$types";

export const GET: RequestHandler = (event) => handleOpenReceive(event);
export const POST: RequestHandler = (event) => handleOpenReceive(event);

native is the request’s RequestEvent, so authorize can check the session your app already has: its cookies, or the event.locals.user your hooks.server.ts sets. The Next.js quickstart explains each hook. They are the same here.

One stack serves the whole server process. Behind a reverse proxy, set adapter-node’s ADDRESS_HEADER (and XFF_DEPTH), so that getClientAddress() returns the payer’s address and not the proxy’s (Rate limiting).

On SvelteKit 2, import the secret as env.NWC_URI from $env/dynamic/private, and import server modules from $lib/server/, with no src/env.ts. The rest is the same. This recipe was checked on SvelteKit 3 only.

Your database

db is a pg Pool, node:sqlite or better-sqlite3, or one of the adapters in Node ORM recipes. With Drizzle, pass the driver underneath it. sv add drizzle sets up Postgres through postgres.js or Neon, which OpenReceive does not take directly. Then give OpenReceive its own small pg Pool on the same DATABASE_URL. It is the same database, not a second one.

Create OpenReceive’s two tables with your migrations (npx openreceive scaffold payments --orm drizzle writes the Drizzle schema), or run paymentsSchemaSql("postgres") from @openreceive/http once. It is idempotent. See Payment storage.

The checkout page

// src/routes/checkout/[reference]/+page.server.ts
import { error } from "@sveltejs/kit";
import { findOrder } from "#lib/server/orders.ts";
import type { PageServerLoad } from "./$types";

export const load: PageServerLoad = async ({ params, cookies }) => {
  const order = await findOrder(params.reference);
  if (!order || order.visitor !== cookies.get("visitor")) error(404);
  return { reference: order.id };
};

<!-- src/routes/checkout/[reference]/+page.svelte -->
<script lang="ts">
  import Checkout from "@openreceive/svelte/checkout.svelte";
  import "@openreceive/svelte/styles.css";
  import type { PageProps } from "./$types";

  let { data }: PageProps = $props();
</script>

<Checkout reference={data.reference} prefix="/openreceive" />

The page renders on the server and starts the checkout in the browser. The payer picks Bitcoin and gets the invoice. Keep it at the order’s own URL: a payer with a swap deposit in flight comes back to it (Swap refunds).

Settings

In production, set them all in the server’s environment. In development, vite dev reads .env for the variables in src/env.ts but keeps the file out of process.env. To try swaps locally, start it with node --env-file=.env node_modules/.bin/vite dev.

No worker or cron job is needed. Each request to the payment routes also checks the wallet for settled invoices, through a lock in your database. A payer who closes the tab is settled on the next request.