An existing app

The starter is a reference, not a requirement. An app you already run becomes a Built-for-Bankroll app by serving a manifest and verifying sessions — this page is that path for Next.js. On another stack, the Quickstart shows the same steps framework-free.

1. Install

npm install @joinbankroll/sdk
npm install -D @joinbankroll/cli

The CLI is for the dev loop and your app tokens; the SDK is everything else.

2. Serve the manifest

One route file, and the SDK owns the format:

app/.well-known/bankroll.jwt/route.ts

import { manifestRoute } from "@joinbankroll/sdk/next";
import { treasuryAddress } from "@joinbankroll/sdk/server";

export const dynamic = "force-dynamic"; // built from the request's own host

export const GET = manifestRoute({
  name: () => "Acme Games",
  launch: "/app",              // where the host boots the app; "/" serves your site
  payments: treasuryAddress,   // null until a treasury key is set — declared once it exists
});

See The manifest for every claim, and serve a square PNG at /.well-known/bankroll-icon.png when you have one.

3. Verify sessions

Every route that matters reads the user from the verified token, never from the request body:

import { requireSession, requireIdentity, Unauthorized } from "@joinbankroll/sdk/next";

export const dynamic = "force-dynamic";

export async function POST(request: Request) {
  const session = await requireSession(request); // throws Unauthorized
  requireIdentity(session);                      // real money moves only for a verified person
  // session.user.wallet — the user's stable id, and payout target
}

On the client, bankrollFetch (or withBankrollToken(fetch)) attaches the token to every request.

4. Move money

The client calls charge(); your server confirms with confirmCharge() and checks payee, mint, amount, and payer before releasing value, then records the signature so it can never be redeemed twice. Payouts are pay() from your treasury. If you already run a database, a UNIQUE column on the signature is the replay guard; if you don’t, the store exists so you don’t have to provision one.

5. Copy the recovery machinery

A charge whose page dies before reporting back still settled — money at your address that nothing points to. The pattern that recovers it (an intent written before the charge, a reference carried on-chain, a sweep that finds what was never reported) is described in Payments, and the starter ships a working implementation. It is app code rather than SDK code today — copy it (MIT) rather than rewrite it:

Copy	What it is
`src/lib/charges.ts`	The settle checks both paths share — live and swept payments get identical scrutiny.
`src/lib/store.ts`	One document per charge and per intent, with the atomic create that is also the replay guard.
`src/lib/sweep.ts`	Finds charges that settled without being reported, by their reference.
`src/app/api/charges/…`	The three routes: start an intent, confirm and list charges, pay one back out.

Adapt charges.ts to your own price and product; the shape is the part worth keeping.

6. Wire the dev loop

bankroll dev tunnels your dev server so a phone can reach it (see Local development). Next.js blocks cross-origin hot-reload by default, so allow the tunnel in next.config.ts:

const nextConfig: NextConfig = {
  allowedDevOrigins: ["*.trycloudflare.com"],
};

Then npx bankroll dev — or make it your dev script, as the starter does.

Get Started

Guides

Reference

Helpers

Changelog

1. Install

2. Serve the manifest

3. Verify sessions

4. Move money

5. Copy the recovery machinery

6. Wire the dev loop

​1. Install

​2. Serve the manifest

​3. Verify sessions

​4. Move money

​5. Copy the recovery machinery

​6. Wire the dev loop

1. Install

2. Serve the manifest

3. Verify sessions

4. Move money

5. Copy the recovery machinery

6. Wire the dev loop