Developers · Base

Build a Base mini app for cashing out USDC.

Use this when your Base app needs a focused cash-out surface instead of a full wallet dashboard. The template is deliberately small: one form, one wallet client, one deposit result.

Clone the Base templateOpen the sell flow
01

Use the starter

  1. 1Clone ADWilkinson/usdctofiat-peerlytics-starters and open templates/base-mini-app.
  2. 2Set NEXT_PUBLIC_APP_URL to the public HTTPS origin before testing discovery surfaces.
  3. 3Keep the form compact: route, amount, payout handle, wallet connect, and result.
  4. 4Call offramp(walletClient, params) with integratorId and referralId so deposits can be attributed.
02

Base-specific requirements

Next.js app

Matches the official Base app quickstart and keeps deployment simple.

Base Account

Gives users a Base-native connection path through @base-org/account.

Viem WalletClient

The off-ramp SDK signs with the wallet client you provide.

Builder Code

Attributes onchain activity after the app is registered on Base.dev.

Real transaction test

A production build is not enough; verify a small Base deposit end to end.

03

Do not expand the surface

  • Do not add a marketing hero before the cash-out form.
  • Do not hide the payout route, amount, or handle behind onboarding copy.
  • Do not claim guaranteed fill speed; buyer demand still controls liquidity.
  • Do not add Builder Code wiring until the real code exists.

Keep exploring

Offramp SDKWebhooksDeveloper hub

Common questions

What should the Base mini app do first?

It should create a real USDCtoFiat seller deposit from a connected Base Account wallet. Start with amount, route, payout handle, and the deposit result before adding anything else.

Does the Base mini app need a separate backend?

Not for the basic cash-out flow. The wallet signs through the client and @usdctofiat/offramp creates the Base deposit. Add a backend only when you need account state, webhooks, or your own order database.

When should I add a Builder Code?

After registering the app on Base.dev and receiving the real code. Until then, keep the integration ready for attribution but do not ship placeholder code as if it were verified.