Beamio cash and USDC

Maturity: Public application (partial). Coinbase / Treasury walletDeposit and Stripe Crypto Onramp session APIs are live on https://beamio.app. Onramp settlement depends on Stripe Crypto Onramp being enabled for the operator account and on the webhook event set. This page is not a claim that every paid session has already settled.

Parent: Beamio whitepaper.

Revision: 2026-08-23.

Product role

Beamio exposes more than one cash rail. They share Stripe or Coinbase as a payment front only when documented. They must not share fulfillment code, destination tokens, or user-facing copy.

Buy USDC with card is the consumer card rail: the user pays with a credit card on Stripe Crypto Onramp, and Stripe sends native USDC on Base directly to the owner EOA. Beamio does not hold inventory USDC or call USDC.transfer.

This chapter is the whitepaper source for deposit semantics. Merchant Fuel Packs and Merchant Kit are listed only so they are not confused with consumer USDC.

Rails (do not merge)

Treasury (sole active): TreasuryBridgeV3 0xa208982212978550594A7FEEB70a61665d129003.

Base USDC: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913.

Base RPC for these reads: https://base-rpc.conet.network. Beamio does not submit the Onramp USDC transfer.

Coinbase / Treasury (walletDeposit)

Consumer Wallet / Home keep Coinbase as the existing add-cash path.

1. User completes Coinbase / x402 settle.
2. Master occupies the Base settle pool for the lock step.
3. Treasury V3 LockMint produces CONET-USDC for the user on CoNET.

This rail is unchanged by the Stripe Onramp product. Clients must keep WALLET_USDC_DEPOSIT_WORKFLOW = 'walletDeposit' for Coinbase.

Buy USDC with card (eoaUsdcStripe)

Consumer path: Home / Wallet → Buy USDC with card. Stripe Crypto Onramp sends native USDC on Base to the owner EOA. Beamio does not accept card cash and then USDC.transfer from an operator settle wallet.

Consumer PWA
  │  POST /api/eoaUsdcStripe/createSession
  │  { walletAddress, amountUsdc6 }
  ▼
Cluster precheck → Master
  │  Resolve owner EOA (if the submitted address is an AA, read factory owner())
  │  POST Stripe /v1/crypto/onramp_sessions
  │    destination_network=base, destination_currency=usdc
  │    lock_wallet_address=true
  │    source_amount + source_currency=usd
  ▼
User completes Stripe Onramp in the system browser
  │
  ├─ return: https://beamio.app/app/?eoa_usdc_stripe=success|cancel&session_id=…
  ├─ poll:   POST /api/eoaUsdcStripe/poll
  └─ hook:   POST /api/stripeBeamioHook  (crypto.onramp_session.*)
        ▼
  Stripe fulfillment_complete → session succeeded
  Optional transaction_id (0x + 64 hex) stored as usdcTxHash

Retired Stripe Checkout (cs_) sessions are marked failed. Users must start a new Onramp deposit.

Amounts

A successful createSession is not proof that USDC has arrived. Success is Stripe fulfillment_complete. Do not treat fulfillment_processing as succeeded.

HTTP (application API host https://beamio.app)

Cluster performs precheck (address, amount bounds). Master creates the Onramp session and holds the in-memory session map. Master does not occupy Settle_BasePool and does not call USDC.transfer on this rail.

Recipient

Onramp creation locks the destination to the owner EOA on Base:

• Preferred client input: Consumer keyID (EOA).
• If the client sends an AA address, the server resolves owner() via the Base (then CoNET) AA factory before creating the Onramp session.

The product does not mint CONET-USDC on this rail and does not send USDC to the AA.

Operator configuration

The operator Stripe account is the StripeBeamio key on the API host’s local ~/.master.json. Merchant Kit Checkout and Consumer Onramp use this account. The account must have Crypto Onramp enabled (including sandbox approval in the Stripe Dashboard).

The only live Dashboard webhook is https://beamio.app/api/stripeBeamioHook. Verification uses STRIPE_WEBHOOK_SECRET_MERCHANT_KIT (environment or the same ~/.master.json). This book does not publish secret values. The Dashboard event set for that endpoint must include crypto.onramp_session.updated (Onramp) and the Merchant Kit checkout.session.* events. Without that secret, Onramp can still be created, but webhook confirmation will abort.

The API still forwards the retired paths /api/eoa-usdc-stripe-webhook and /api/merchant-kit-stripe-webhook to the same stripeBeamioHook handler. Do not add those URLs in the Stripe Dashboard. https://hooks.conet.network/api/stripeHook is not a Beamio live hook.

Onramp handlers must ignore checkout.session.* for consumer USDC. Those events must not trigger operator inventory transfers or Merchant Kit fulfillment on the Onramp rail.

What this page does not cover

• Merchant Fuel Pack checkout (B-Units merchandising).
• POS Charge / Top-up (program points + B-Unit fees). See POS terminal.
• Cross-chain Treasury mechanics beyond naming the V3 proxy. See Decentralized cross-chain Treasury.

Trust boundary

Related

• Beamio
• Consumer PWA
• Merchant OS
• L1 assets
• Decentralized cross-chain Treasury