ZKsync SSO

A user & developer friendly modular smart account implementation on ZKsync; simplifying user authentication, session management, and transaction processing.

Features and Goals

Caution

ZKsync SSO is under active development and is not yet feature complete. Use it to improve your development applications and tooling. Please do not use it in production environments.

• 🧩 Modular smart accounts based on ERC-7579
• 🔑 Passkey authentication (no seed phrases)
• ⏰ Sessions w/ easy configuration and management
• 💰 Integrated paymaster support
• ❤️‍🩹 Account recovery (Coming Soon)
• 💻 Simple SDKs : JavaScript, iOS/Android (Coming Soon)
• 🤝 Open-source authentication server
• 🎓 Examples to get started quickly

Getting started

Install the ZKsync SSO SDK package:

npm i zksync-sso

Add ZKsync SSO connector to your app (using wagmi):

import { zksyncSsoConnector, callPolicy } from "zksync-sso/connector";
import { zksyncSepoliaTestnet } from "viem/chains";
import { createConfig, connect } from "@wagmi/core";
import { erc20Abi } from "viem";

const ssoConnector = zksyncSsoConnector({
   // Optional session configuration, if omitted user will have to sign every transaction via Auth Server
   session: {
      expiry: "1 day",

      // Allow up to 0.1 ETH to be spend in gas fees
      feeLimit: parseEther("0.1"),

      transfers: [
         // Allow ETH transfers of up to 0.1 ETH to specific address
         {
            to: "0x188bd99cd7D4d78d4E605Aeea12C17B32CC3135A",
            valueLimit: parseEther("0.1"),
         },
      ],

      // Allow calling specific smart contracts (e.g. ERC20 transfer):
      contractCalls: [
         callPolicy({
            address: "0xa1cf087DB965Ab02Fb3CFaCe1f5c63935815f044",
            abi: erc20Abi,
            functionName: "transfer",
            constraints: [
               // Only allow transfers to this address. Or any address if omitted
               {
                  index: 0, // First argument of erc20 transfer function, recipient address
                  value: "0x6cC8cf7f6b488C58AA909B77E6e65c631c204784",
               },

               // Allow transfering up to 0.2 tokens per hour
               // until the session expires
               {
                  index: 1,
                  limit: {
                     limit: parseUnits("0.2", TOKEN.decimals),
                     period: "1 hour",
                  },
               },
            ],
         }),
      ],
   },
});

const wagmiConfig = createConfig({
   connectors: [ssoConnector],
   ..., // your wagmi config https://wagmi.sh/core/api/createConfig
});

const connectWithSSO = () => {
   connect(wagmiConfig, {
      connector: ssoConnector,
      chainId: zksyncSepoliaTestnet.id, // or another chain id that has SSO support
   });
};

Find more information here in our docs.

Local Development

This monorepo is comprised of the following packages, products, and examples:

• packages/sdk is the zksync-sso JavaScript SDK
• packages/auth-server is the Auth Server used for account creation and session key management
• packages/contracts are the on-chain smart contracts behind ZKsync SSO accounts
• examples/nft-quest is an app demonstrating the use of ZKsync SSO w/ sessions
• examples/nft-quest-contracts are the smart contracts for nft-quest
• examples/demo-app is a test app mostly used for CI testing
• examples/bank-demo is an app demonstrating the fully embedded experience

Running development

1. Install workspace dependencies with PNPM.

   pnpm install

2. If creating new packages: use pnpm and workspace protocol to link SDK in the new folder.

3. Install foundry-zksync:

   curl -L https://raw.githubusercontent.com/matter-labs/foundry-zksync/main/install-foundry-zksync | bash

4. Start a local node:

   npx zksync-cli dev start

5. Compile and deploy contracts to the local node:

   # Compile and deploy contracts
   cd packages/contracts
   pnpm build
   pnpm run deploy

6. Start the demo application:

   pnpm nx dev demo-app

Your local Auth Server will be running at http://localhost:3002/, and the demo app will be running at http://localhost:3004/.

Running commands

Use the NX CLI to run project commands, however PNPM is still usable as an alternative. NX project names are based on the name defined in each project's project.json which are set to match the directory name.

pnpm nx <target> <project>
# Example
pnpm nx build sdk

To run a command in multiple projects, use the run-many command.

pnpm nx run-many -t <target> --all           # for all projects
pnpm nx run-many -t <target> -p proj1 proj2  # by project
pnpm nx run-many --targets=lint,test,build   # run multiple commands

Some commands are inferred and built-in with NX, thus you may not see commands available from via the package.json. To review all the available commands in a project:

pnpm nx show project <project> --web

Lint project

At the root level of the monorepo, run the pnpm run lint command to run linting across the project.

To fix lint issues that come up from linting, run the pnpm run lint:fix command.

Running/Debugging End-to-End Tests

To execute the end-to-end tests for the demo-app (or similarly for nft-quest), you'll need to do some setup:

1. Start era_test_node (In a separate terminal, run npx zksync-cli dev start)
2. Deploy the smart contracts, pnpm nx deploy contracts

Once the local node is configured with the smart contracts deployed, you can run the e2e tests:

pnpm nx e2e demo-app

To debug the end-to-end tests:

pnpm nx e2e:debug demo-app