ENS-7828-Resolver

Quick Test

npm install
npx tsx test-resolver.js

Run these commands to install dependencies and quickly verify the library resolves EIP-7828 names across multiple chains.

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See Architecture Overview →

A fully-featured TypeScript library for parsing, resolving and displaying EIP-7828-style human-readable, chain-specific ENS names.

Overview

This library implements the EIP-7828 specification for human-readable, chain-specific ENS names. It supports parsing and resolving names like:

• alice.eth@base
• vitalik.eth@1
• bob.app.eth@optimism
• test.eth@base#abcd1234

Features

• EIP-7828 Compliant: Full implementation of the EIP-7828 specification
• Multi-chain Support: Resolves addresses across Ethereum, Base, Optimism, Arbitrum, Polygon, Solana, Bitcoin, and more
• Standards Compliant:
  • Multi-coin address lookup via ENSIP-9
  • Chain metadata via CAIP-2/CAIP-10
  • Future support for EIP-7785 ENS chain specification
• Zero-friction Installation: Pre-compiled chain mapping shipped in package

Installation

npm install @unruggable-labs/ens-7828-resolver

Quick Start

import { resolve7828 } from "@unruggable-labs/ens-7828-resolver";

// Resolve an ENS name on a specific chain
const result = await resolve7828("vitalik.eth@ethereum");

console.log(result);
// {
//   address: '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045',
//   chainId: 1,
//   chainName: 'Ethereum Mainnet',
//   caip10: 'eip155:1:0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045',
//   coinType: 60
// }

API Reference

Core Functions

resolve7828(input: string, options?: ResolveOptions): Promise<ResolvedAddress>

Resolves an EIP-7828 formatted name to an address.

Parameters:

• input: EIP-7828 formatted name (e.g., "alice.eth@base")
• options: Optional configuration
  • provider: ethers.js provider instance
  • rpcUrl: RPC URL for the provider

Returns: Promise resolving to ResolvedAddress

Example:

const result = await resolve7828("ndeto.eth@solana");
// {
//   address: 'GwjiVpwPmfmh8T4EXqtsiuU1YoYknxAKLe6ujMDgLgmV',
//   chainId: 'So11111111111111111111111111111111111111112',
//   chainName: 'Solana',
//   caip10: 'solana:So11111111111111111111111111111111111111112:GwjiVpwPmfmh8T4EXqtsiuU1YoYknxAKLe6ujMDgLgmV',
//   coinType: 501
// }

parse7828Name(input: string): Parsed7828Name

Parses an EIP-7828 name without resolving it.

Parameters:

• input: EIP-7828 formatted name

Returns: Parsed7828Name object

Example:

const parsed = parse7828Name("alice.eth@base#abcd1234");
// {
//   ensName: "alice.eth",
//   chainSpec: "base",
//   checksum: "abcd1234"
// }

validate7828Name(input: string): boolean

Validates an EIP-7828 name format.

Parameters:

• input: EIP-7828 formatted name

Returns: boolean indicating if the name is valid

Chain Resolution

resolveChain(chainSpec: string): ResolvedChain

Resolves a chain specification to chain information.

Supported formats:

• Chain ID: 1, 8453, 10
• Short names: base, oeth, arb1
• Display names: ethereum, optimism, arbitrum, polygon

Future EIP-7785 Support:

• ENS domain-based specs: base.l2.eth, optimism.l2.eth (planned)

Utility Functions

format7828Name(address: ResolvedAddress): string

Formats a resolved address as an EIP-7828 name string (e.g., <address>@<chainName>).

Supported Chains

The library includes pre-compiled chain mappings for popular networks:

EVM Chains

Chain	Chain ID	Short Name	Display Name	Coin Type
Ethereum	1	eth	ethereum	60
Base	8453	base	base	2147492101
Optimism	10	oeth	optimism	2147483658
Arbitrum One	42161	arb1	arbitrum	2147525809
Polygon	137	pol	polygon	966
BNB Smart Chain	56	bnb	bnb	714
Avalanche	43114	avax	avalanche	9000
Fantom	250	ftm	fantom	250
Celo	42220	celo	celo	2147525868

Non-EVM Chains

Chain	Short Name	Display Name	Coin Type	Namespace
Solana	solana	solana	501	solana
Bitcoin	bitcoin	bitcoin	0	bip122

Chain Specification Formats

Valid EIP-7828 Examples

# Chain ID format
alice.eth@1
vitalik.eth@8453

# Display name format
bob.eth@ethereum
test.eth@base
clowes.eth@solana

# Short name format
user.eth@oeth
app.eth@arb1

Invalid Formats

# Full CAIP-2 in chainSpec (not supported)
alice.eth@eip155:1
test.eth@solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdpKuc147dw2N9d

# Invalid ENS name
invalid@1
no-at-symbol.eth

Future Standards Support

For the long-term vision of decentralized multi-chain ENS resolution—including how ERC-7930 and ERC-7785 mapping will work together, see ARCHITECTURE.md for details on the end-state and technical flow.

Development

Building

# Install dependencies
npm install

# Build the library
npm run build

# Run tests
npm test

Adding New EVM Chains

To add a new EVM chain to the pre-populated list:

1. Edit scripts/chains.ts:

   export const MAJOR_CHAINS = [
     // ... existing chains
     { chainId: YOUR_CHAIN_ID, identifier: "your-chain" },
   ];

2. Regenerate chain mapping:

   npm run prepare

Adding Non-EVM Chains

To add a new non-EVM chain:

1. Edit scripts/chains.ts:

   export const MANUAL_CHAINS: ChainInfo[] = [
     // ... existing chains
     {
       chainId: "your-chain", // String identifier
       shortName: "your-chain",
       name: "Your Chain",
       slip44: YOUR_COIN_TYPE, // From SLIP-44 standard
       namespace: "your-namespace", // e.g., "solana", "bip122"
       reference: "your-genesis-hash-or-identifier",
     },
   ];

2. Regenerate chain mapping:

   npm run prepare

Coin Type Derivation

The library uses the following rules for coin type derivation:

• EVM Chains:
  • Coin type is derived using ENSIP-11:
    • Formula: (chainId | 0x80000000) >>> 0 (i.e., 0x80000000 + chainId)
    • Example: Chain ID 42220 (Celo) → Coin Type 2147525868
• Non-EVM Chains:
  • Coin type is the SLIP-44 value for the chain (no offset):
    • Example: Solana: 501, Bitcoin: 0

Note: Coin type is always represented as a uint (unsigned integer), and is the value used by ENS contracts and multicoin records. For EVM chains, ENSIP-11 is the source of truth; for non-EVM chains, SLIP-44 is the source of truth.

Contributing

Adding New Chains

1. EVM Chains: Add to MAJOR_CHAINS in scripts/chains.ts
2. Non-EVM Chains: Add to MANUAL_CHAINS in scripts/chains.ts
3. Regenerate: Run npm run prepare to update mappings
4. Test: Add test cases to test-library.js

Development Workflow

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Run npm run prepare && npm run build
5. Submit a pull request

Testing

# Run the test suite
npx tsx test-resolver.js

License

MIT