Skip to main content
Account abstraction (AA) replaces signed EOA transactions with a more expressive primitive: the UserOperation. With the Startale AA SDK you build on top of an ERC-7579 modular account that is settled through SCS bundler and paymaster infrastructure, so you can deliver gas sponsorship, ERC-20 gas payment, social recovery, smart sessions, batched calls, and EIP-7702 delegation without operating any of that infrastructure yourself.

​
The UserOperation lifecycle

A UserOperation is the ERC-4337 payload that describes intent for a smart account. Wallets sign UserOperations and submit them to a bundler, which validates and packages them into a single onchain transaction sent to the EntryPoint contract. The EntryPoint then drives execution against your account. Every step in that diagram is exposed as a typed action on StartaleAccountClient, which is the object returned by createSmartAccountClient.

​
What is a UserOperation, really

Where an EOA transaction is (to, value, data, signature), a UserOperation is (sender, nonce, callData, gasLimits, paymasterAndData, signature, ...). The extra fields unlock four things that EOAs cannot do:
  • Custom signature validation. Any module installed as a validator can decide whether the signature is valid, so you are not bound to a single ECDSA key.
  • Gas sponsorship and token gas. A paymaster can co-sign the UserOp to pay gas on the user’s behalf, or to accept an ERC-20 token as payment.
  • Batched execution. A single UserOp can carry multiple calls and they all succeed or revert together.
  • Programmable execution. Modules hook into the validation and execution flow of every UserOp.

​
How modules hook into the execution flow

Startale smart accounts implement ERC-7579, which defines a small contract surface for plugging in independent modules. When a UserOperation reaches your account, it walks through this pipeline: toStartaleSmartAccount accepts each of these as a parameter (validators, prevalidationHooks, hook, executors, fallbacks), and StartaleAccountClient exposes ERC-7579 actions (installModule, uninstallModule, isModuleInstalled, getInstalledValidators, getInstalledExecutors, getActiveHook) so you can install or remove modules at runtime.

​
What you can build

The SDK and modular account together give you a small but powerful set of primitives. Everything below is a first-class capability of @startale-scs/aa-sdk:

Sponsored transactions

Pay gas for your users via a managed or self-funded SCS paymaster, with optional gas policies that scope sponsorship by user, contract, or rate limit.

ERC-20 gas payment

Let users pay gas in ASTR, USDC, or other supported tokens through the Startale Token Paymaster. Quote tokens with getTokenPaymasterQuotes.

Batched and parallel calls

Send multiple contract calls atomically in one UserOperation, or use two-dimensional nonces to run independent UserOps in parallel.

Smart sessions

Issue scoped, time-bound session keys so users do not have to re-sign every action. Backed by the Smart Sessions validator module.

Social recovery

Add an ERC-7579 recovery module that lets a guardian set with a configurable threshold rotate the account’s signer.

EIP-7702 delegation

Upgrade an existing EOA into a Startale Smart Account without changing the address, then use it like any other modular account.

​
SCS infrastructure

The SDK alone is not enough to send a UserOperation onchain; you also need a bundler and a paymaster. SCS hosts both behind a single API key issued from the SCS Portal, so you do not need to operate them yourself.

​
Paymaster models

SCS exposes two paymaster modes from the same RPC. Both pass a paymasterId through paymasterContext; the difference is who issues the id and how it is funded. In both modes, the call site looks the same:
For ERC-20 gas payment, swap paymasterId for token:
The full list of supported tokens per network is in Supported networks.

​
Where to go next

Quickstart

Send your first UserOperation in a single Node.js script.

Portal setup

Provision an API key, create a paymaster, and set gas policies.

Installation

Install dependencies and choose a signer for any framework.

Smart account setup

Create the account, wire up the client, and persist it across renders.