Introduction

Vellar SDK (vellar-sdk) is the fastest way to add a passkey-powered, self-custodial Stellar wallet to your app — without handling private keys, seed phrases, or the low-level submission plumbing.

One install, one object:

const vellar = createVellarWallet({ network, appName, kit, sac, backend, isValidAddress });
await vellar.create({ username });        // passkey → smart account
await vellar.pay({ to, amount, token });  // simulate → passkey → sponsored submit

What you get

• Passkeys, not seed phrases — WebAuthn (Face ID / Touch ID / security keys). Keys live in the device's secure enclave and never leave it.
• Smart-contract accounts — each wallet is a Soroban smart wallet, so it can carry programmable policies (spending limits, multisig, allowlists).
• Fee-sponsored — users hold no XLM for fees; submission is sponsored server-side.
• No key custody, no silent signing — the SDK never holds secrets and never signs without an explicit passkey prompt.
• Agentic payments (x402) — pay HTTP-402 resources from the smart account, and give an AI agent a scoped key that pays on its own within limits the chain enforces, not your code. See x402.

For the agent economy

Vellar isn't only a human wallet — it's built for autonomous agents that spend money. Three surfaces make that safe:

• Agent keys — mint a scoped session key an agent holds itself. Give your agent a budget, not your keys.
• Policies — a spending-limit policy caps how much; a verified-only policy restricts the agent to contracts with reproducible, verified source (provenance, not an audit). Both are enforced on-chain in the wallet's __check_auth, so a compromised agent can't exceed them.
• x402 Facilitator — Vellar runs a hosted x402 verify/settle facilitator with Bazaar discovery, so agents can find and pay for services (and it accepts the policy-governed payments other facilitators reject).

Who this is for

Developers building on Stellar who want login + a wallet without becoming wallet-infrastructure experts, teams who want programmable, on-chain security (spending limits, co-signers) instead of client-side checks that can be bypassed, and anyone building AI agents that need to transact under limits they can trust.

Status

Early and evolving. Testnet-ready; mainnet use is pending a security review. APIs may change before 1.0.

New here? Go to Installation, then the Quickstart to get a working wallet in a few minutes.