eERC

Install

For apps already using the kit:

pnpm add @avalabs/eerc-sdk

Minimal base install before eERC:

pnpm add @avalabs/avacloud-kit-ui-preview react react-dom

If your workspace requires explicit peer installs, add:

pnpm add wagmi viem @tanstack/react-query @connectrpc/connect @connectrpc/connect-query

For browser apps, import the polyfill entry once before your app renders:

import '@avalabs/avacloud-kit-ui-preview/eerc-polyfills';

const nextConfig = {
  webpack: (config, { isServer, webpack }) => {
    config.plugins.push(
      new webpack.NormalModuleReplacementPlugin(/^node:/, (resource) => {
        resource.request = resource.request.replace(/^node:/, '');
      }),
    );

    if (!isServer) {
      config.resolve.fallback = {
        ...config.resolve.fallback,
        crypto: false,
        fs: false,
        path: false,
        stream: false,
        os: false,
        buffer: false,
      };
    }

    return config;
  },
};

export default nextConfig;

Shared Config

Standalone and converter mode both use the same five circuit artifacts. Only the contract config changes.

import type { EercCircuitConfig, EercContractConfig } from '@avalabs/avacloud-kit-ui-preview/eerc';

export const EERC_STANDALONE: EercContractConfig = {
  contractAddress: '0x...',
};

export const EERC_CONVERTER: EercContractConfig = {
  contractAddress: '0x...',
  tokenAddress: '0x...',
};

const CUSTOM_CIRCUITS: EercCircuitConfig = {
  register: {
    wasm: 'https://example.com/eerc/registration/registration.wasm',
    zkey: 'https://example.com/eerc/registration/circuit_final.zkey',
  },
  transfer: {
    wasm: 'https://example.com/eerc/transfer/transfer.wasm',
    zkey: 'https://example.com/eerc/transfer/transfer.zkey',
  },
  mint: {
    wasm: 'https://example.com/eerc/mint/mint.wasm',
    zkey: 'https://example.com/eerc/mint/mint.zkey',
  },
  withdraw: {
    wasm: 'https://example.com/eerc/withdraw/withdraw.wasm',
    zkey: 'https://example.com/eerc/withdraw/circuit_final.zkey',
  },
  burn: {
    wasm: 'https://example.com/eerc/burn/burn.wasm',
    zkey: 'https://example.com/eerc/burn/burn.zkey',
  },
};

export const EERC_DEMO_OVERRIDE: EercContractConfig = {
  contractAddress: '0x...',
  circuitUrls: CUSTOM_CIRCUITS,
};

circuitUrls is optional in both EercContractConfig and EercProviderProps. When you omit it, EercProvider uses the shared AvaCloud bundle under https://assets.avacloud.io/eerc/v0.0.4/<circuit>/... by default. For example, registration resolves to .../registration/registration.wasm and .../registration/circuit_final.zkey. Pass circuitUrls only when you need a different bundle, such as demo contracts or a self-hosted verifier set. The package also exports DEFAULT_EERC_CIRCUIT_URLS if you want to inspect or reuse the hosted defaults directly.

Any override must still include all five entries: register, transfer, mint, withdraw, and burn. Circuit URLs must be browser-loadable paths or HTTPS URLs.

The predeployed demo contracts on this page use demo-specific circuit overrides. Fresh kit deployments target the shared v0.0.4 bundle by default.

Mode Overview

Standalone Mode

Use standalone mode when the encrypted token is the token of record.

import {
  EercBalance,
  EercBurnForm,
  EercGate,
  EercMintForm,
  EercProvider,
  EercTransferForm,
} from '@avalabs/avacloud-kit-ui-preview/eerc';

export function StandaloneExample() {
  return (
    <EercProvider {...EERC_STANDALONE}>
      <EercGate featureName="encrypted transfers" withCard={false}>
        <EercBalance />
        <EercTransferForm />
        <EercMintForm />
        <EercBurnForm />
      </EercGate>
    </EercProvider>
  );
}

Use standalone when:

• there is no separate public ERC-20 backing asset
• you want direct encrypted balance operations
• the contract owner can mint to any registered standalone recipient
• registered users can burn from their own encrypted balance

Converter Mode

Use converter mode when you want to wrap a public ERC-20 and move between public and encrypted balances.

import {
  EercBalance,
  EercConverterDepositForm,
  EercConverterWithdrawForm,
  EercGate,
  EercProvider,
  EercTransferForm,
  useEercConverter,
} from '@avalabs/avacloud-kit-ui-preview/eerc';

function CustomConverterActions() {
  const { deposit, withdraw, status, error } = useEercConverter();

  return null;
}

export function ConverterExample() {
  return (
    <EercProvider {...EERC_CONVERTER}>
      <EercGate featureName="encrypted converter" withCard={false}>
        <EercBalance />
        <EercConverterDepositForm />
        <EercConverterWithdrawForm />
        <EercTransferForm />
      </EercGate>
    </EercProvider>
  );
}

Converter-specific notes:

• converter deployment is not permanently bound to one ERC-20; tokenAddress is just the currently selected public token for converter balance, deposit, and withdraw flows
• converter decimals are the encrypted-side precision stored on the eERC contract, not the underlying ERC-20's decimals
• when the selected ERC-20 uses a different decimal count, deposits and withdrawals scale against the converter contract's fixed precision
• 18 is the safest default if one converter should support many different ERC-20s
• EercConverterDepositForm handles ERC-20 approval automatically when allowance is too low
• approval defaults to exact amount rather than unlimited approval
• EercConverterWithdrawForm converts encrypted balance back into the public ERC-20
• the docs demo includes a faucet so you can test the full flow on Fuji without leaving the page

Fuji Demo Addresses

Live Demos

Standalone Live Demo

Connect a Fuji wallet to complete eERC setup, view your encrypted balance, and test standalone transfer and the demo contract's custom mint policy. The burn card is shown but disabled because this predeployed standalone contract uses an older burn implementation than the current kit target.

Converter Live Demo

Connect a Fuji wallet to request demo tokens, move between public and encrypted balance, and test a private transfer in converter mode.

Deploy Your Own eERC

Use the deployment wizard to deploy a full eERC contract stack (cryptographic library, verifiers, registrar, and token) to any EVM chain. The wizard walks through chain selection, mode configuration, infrastructure deployment, token deployment, and optional auditor assignment.

After deployment, you will receive all contract addresses and can download them as JSON for your records.

Bundler Notes

For Vite/browser SPA apps, the eerc-polyfills import above is enough.

For Next.js, use the webpack config above in addition to the polyfill import.