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Sponsor Smart Wallets

Smart Wallets use a different structure from Classic Wallets, which also makes the sponsorship process different.

  • Classic Wallets must hold a reserve of XLM based on account usage (e.g. account creation, adding trustlines). They also pay a small Inclusion Fee per transaction.
  • Smart Wallets are contracts. They do not require reserves, but they pay both an Inclusion Fee and a Resource Fee. The Resource Fee is calculated based on the resource consumption declared in the transaction, including storage, computation, and bandwidth.

📖 Learn more about Fees, Resource Limits, and Metering

📖 Learn more about Persisting Data in Smart Contracts

📖 Learn more about State Archival

To improve UX, these fees can be covered by a sponsoring account, so users don't need to hold XLM. This makes onboarding into smart wallets seamless.

Sponsoring With the Wallet Backend​

The stellar/wallet-backend project provides server-side tooling to make user onboarding with smart wallets seamless.

Key Features​

  • Fee Sponsorship ("Gasless" UX)
    Uses fee-bump transactions so a distribution account pays transaction fees.
  • Channel Accounts
    Manages sequence numbers and scales throughput by using pre-funded channel accounts.
  • API Access
    Exposes endpoints for building, signing, and submitting transactions, secured by JWT-based authentication.

Sponsorship Flow​

  1. Frontend (Smart Wallet App)

    • User signs an operation according to their wallet's contract logic (e.g., passkey, policy signer).
    • App sends the signed payload to the backend.
  2. Backend (wallet-backend)

    • Builds the transaction using a channel account for sequence numbers.
    • Wraps it in a fee-bump transaction so the distribution account pays the fee (and any reserve if needed).
    • Returns the transaction to the frontend which can then submit it.
  3. Result

    • User's wallet action succeeds.
    • User never needed to hold XLM for fees or reserves.
    • Sponsor absorbs costs and can manage them.