> For the complete documentation index, see [llms.txt](https://docs.grxchain.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.grxchain.io/7.2-integrations.md).

# 7.2 Integrations

GRX Chain is EVM-compatible and built for open, standards-based integration. This page provides wallet settings, core contracts, JSON-RPC details, security guidance, and copy-paste code for rapid onboarding.

### Quick Start

#### Add Network (MetaMask → UI)

**Mainnet**

* Network: `GRX Chain`
* RPC: `https://rpc.grxchain.io`
* Chain ID: `1110` (hex `0x456`)
* Currency: `GRX`
* Block Explorer: `https://grxscan.io`

**Testnet**

* Network: `GRX Chain Testnet`
* RPC: `https://testnet.grxchain.io`
* Chain ID: `2507` (hex `0x9CB`)
* Currency: `GRX`
* Block Explorer: `https://testnet.grxscan.io`

#### Programmatic Add (MetaMask)

```js
// Mainnet
await window.ethereum.request({
  method: 'wallet_addEthereumChain',
  params: [{
    chainId: '0x456',
    chainName: 'GRX Chain',
    nativeCurrency: { name: 'GRX', symbol: 'GRX', decimals: 18 },
    rpcUrls: ['https://rpc.grxchain.io'],
    blockExplorerUrls: ['https://grxscan.io']
  }]
});

// Testnet
await window.ethereum.request({
  method: 'wallet_addEthereumChain',
  params: [{
    chainId: '0x9CB',
    chainName: 'GRX Chain Testnet',
    nativeCurrency: { name: 'GRX', symbol: 'GRX', decimals: 18 },
    rpcUrls: ['https://testnet.grxchain.io'],
    blockExplorerUrls: ['https://testnet.grxscan.io']
  }]
});
```

### Network Details

#### Mainnet

* **Network Name:** GRX Chain
* **RPC:** `https://rpc.grxchain.io`
* **Chain ID:** `1110` (hex `0x456`)
* **Symbol:** `GRX`
* **Explorer:** `https://grxscan.io`

**Core Contracts**

* Multicall: `0x2cd9E100Ca0d883A00eC8Ce635EbD4C17508FE3B`
* **WGRX (Wrapped GRX):** `0x45C7287F897B3A79Cd3f6e4F14B4CE568f023bD5`
* GRXswap Factory: `0xc7316818841f355c5107753A3f3FDEA799BD25f6`
* GRXswap Router v2: `0x28fC93b8a20570f2B59d5CA9f8a1dA02C4DBcDF5`
* Pair Init Code Hash: `0xb23d9a8f0a03ecd8f95e43ab1025c71bb79f1cb7128d40546417bfb4b2a74d9c`

**Canonical Tokens**

* USDT (pegged, 6d): 0x173462F5eb7CA0D1ab6aaea846fEFe85A28029E2
* BTC (pegged, 8d): `0x2F4632ABAd26A1FF9212a76597fb3c3d8539E275`
* ETH (pegged, 18d): `0x02D129c8A26839c814925eE0f1D320F63114E1FE`

#### Testnet

* **Network Name:** GRX Chain Testnet
* **RPC:** `https://testnet.grxchain.io`
* **Chain ID:** `2507` (hex `0x9CB`)
* **Symbol:** `GRX`
* **Explorer:** `https://testnet.grxscan.io`
* **Faucet:** `https://faucet.grxchain.io`

### Chain Parameters

* **Average block time:** \~2s
* **Recommended confirmations:** 12 (retail), 60 (exchange/critical)
* **Gas model:** Legacy (pre-1559). When/if 1559 is enabled, we’ll publish `maxFeePerGas` / `maxPriorityFeePerGas` guidance.
* **Target block gas limit:** \~30,000,000
* **Finality:** Probabilistic; short reorgs are rare but possible. Wait the confirmations above.
* **EVM/EIP support:** EIP-155 (chain ID), EIP-2718 (typed tx), EIP-2930 (access list). 1559 TBD via governance.

### Bridging

**Official bridge:** **Only via GroveX** — `https://grovex.io`\
Do not use third-party bridges unless later listed on the Official Channels page.

**Directions (current)**

* Inbound → GRX Chain: supported assets (e.g., ETH, BTC, USDT) credited as pegged assets/WGRX where applicable.
* Outbound ← GRX Chain: WGRX/pegged assets back to source networks (where supported).

**Notes**

* Exchange-mediated, may require KYC and an account.
* Fees/limits/timelines published on GroveX and may change.
* Show a domain check in UIs (must equal `grovex.io`); warn about look-alike domains.

**Config (JSON)**

```json
{
  "bridge": {
    "provider": "GroveX",
    "url": "https://grovex.io",
    "supported": {
      "inbound": ["ETH", "BTC", "USDT", "WGRX"],
      "outbound": ["WGRX", "USDT", "BTC", "ETH"]
    },
    "requirements": { "kyc": true, "account": true },
    "confirmations": { "grxChain": 12 },
    "warnings": [
      "Only use grovex.io for bridging.",
      "Beware of look-alike domains and fake support."
    ]
  }
}
```

### JSON-RPC

* **Public RPC:** `https://rpc.grxchain.io` (mainnet), `https://testnet.grxchain.io` (testnet)
* **WebSocket:** `wss://rpc.grxchain.io/ws`, `wss://testnet.grxchain.io/ws`
* **Rate limits (suggested to publish):** HTTP 50 req/s/IP (burst 100/10s); WS 1 stream, \~2000 msgs/min/IP
* **Headers:** `X-RateLimit-Limit`, `X-RateLimit-Remaining`, `Retry-After`
* **Errors:** `429` = backoff+jitter; `-32005` log range too large; `-32602` invalid params
* **CORS:** enabled for common wallets; avoid cross-origin POSTs from untrusted pages

**Health check**

```bash
curl -s -X POST https://rpc.grxchain.io \
 -H "Content-Type: application/json" \
 -d '{"jsonrpc":"2.0","id":1,"method":"eth_chainId","params":[]}'
# Expect: 0x456
```

**Gas price (legacy)**

```bash
curl -s -X POST https://rpc.grxchain.io \
 -H "Content-Type: application/json" \
 -d '{"jsonrpc":"2.0","id":1,"method":"eth_gasPrice","params":[]}'
```

**WebSocket tips**\
Use keepalive ping \~25s, reconnect with exponential backoff. On drops, resume from the last confirmed block.

### Explorer & APIs

* **Explorer:** `https://grxscan.io`
* **Testnet Explorer:** `https://testnet.grxscan.io`

**Examples** *(adjust to GRXscan’s API spec)*

```bash
# Tx by hash
curl -s "https://grxscan.io/api?module=transaction&action=gettxinfo&txhash=<TX_HASH>"

# Address tx list
curl -s "https://grxscan.io/api?module=account&action=txlist&address=<ADDRESS>&page=1&offset=25"
```

### Developer Tooling

* **Frameworks:** Remix, Hardhat, Truffle
* **Libraries:** ethers.js, web3.js
* **Infra:** Use public RPCs for dev; for production, run your own node or a provider.

**Hardhat sample**

```js
export default {
  solidity: "0.8.24",
  networks: {
    grx: { url: "https://rpc.grxchain.io", chainId: 1110, accounts: [process.env.PRIVATE_KEY].filter(Boolean) },
    grxTestnet: { url: "https://testnet.grxchain.io", chainId: 2507, accounts: [process.env.PRIVATE_KEY].filter(Boolean) }
  }
}
```

**ethers.js — read WGRX balance**

```js
import { ethers } from "ethers";
const provider = new ethers.JsonRpcProvider("https://rpc.grxchain.io");
const wgrx = new ethers.Contract(
  "0x45C7287F897B3A79Cd3f6e4F14B4CE568f023bD5",
  ["function balanceOf(address) view returns (uint256)"],
  provider
);
const bal = await wgrx.balanceOf("0xYourAddress");
console.log("WGRX balance:", bal.toString());
```

### GRXswap (Router v2) — Examples

**Swap exact tokens for tokens (ethers v6)**

```js
import { ethers } from "ethers";
const provider = new ethers.JsonRpcProvider("https://rpc.grxchain.io");
const signer = new ethers.Wallet(process.env.PRIVATE_KEY, provider);

const router = new ethers.Contract(
  "0x28fC93b8a20570f2B59d5CA9f8a1dA02C4DBcDF5",
  [
    "function swapExactTokensForTokens(uint256,uint256,address[] calldata,address,uint256) returns (uint256[] memory)",
    "function getAmountsOut(uint256,address[] calldata) view returns (uint256[] memory)"
  ],
  signer
);

const WGRX = "0x45C7287F897B3A79Cd3f6e4F14B4CE568f023bD5";
const USDT = "0x1d3bc9646d126D379b4da4d71c8a4fa6b830Dd20";

const amountIn = ethers.parseUnits("10", 18);
const path = [WGRX, USDT];

const amounts = await router.getAmountsOut(amountIn, path);
const minOut = (amounts[1] * 995n) / 1000n; // 0.5% slippage
const tx = await router.swapExactTokensForTokens(
  amountIn, minOut, path, await signer.getAddress(), Math.floor(Date.now()/1000)+600
);
await tx.wait();
```

**Wrap/unwrap WGRX**

```js
const wgrx = new ethers.Contract(
  "0x45C7287F897B3A79Cd3f6e4F14B4CE568f023bD5",
  ["function deposit() payable", "function withdraw(uint256 wad)"],
  signer
);

// Wrap 1 GRX -> 1 WGRX
await (await wgrx.deposit({ value: ethers.parseUnits("1", 18) })).wait();

// Unwrap 1 WGRX -> 1 GRX
await (await wgrx.withdraw(ethers.parseUnits("1", 18))).wait();
```

**Best practices**\
Approve the Router before first swap: `await erc20.approve(router, amount)`\
Validate pair addresses against Factory; verify init code hash.\
Use Multicall for batched reads; keep batches <100 calls or <500k gas per aggregate.

### Official Token List (JSON)

```json
{
  "name": "GRX Official Tokens",
  "timestamp": "2025-10-30T00:00:00Z",
  "version": { "major": 1, "minor": 0, "patch": 0 },
  "tags": { "pegged": { "description": "Externally backed or bridged representations" } },
  "logoURI": "https://grxchain.io/logo.png",
  "keywords": ["grx", "wgrx", "official"],
  "tokens": [
    { "chainId": 1110, "address": "0x45C7287F897B3A79Cd3f6e4F14B4CE568f023bD5", "name": "Wrapped GRX", "symbol": "WGRX", "decimals": 18 },
    { "chainId": 1110, "address": "0x1d3bc9646d126D379b4da4d71c8a4fa6b830Dd20", "name": "Tether USD (Pegged)", "symbol": "USDT", "decimals": 6, "tags": ["pegged"] },
    { "chainId": 1110, "address": "0x2F4632ABAd26A1FF9212a76597fb3c3d8539E275", "name": "Bitcoin (Pegged)", "symbol": "BTC", "decimals": 8, "tags": ["pegged"] },
    { "chainId": 1110, "address": "0x02D129c8A26839c814925eE0f1D320F63114E1FE", "name": "Ether (Pegged)", "symbol": "ETH", "decimals": 18, "tags": ["pegged"] }
  ]
}
```

### Network Object (Mainnet + Testnet)

```json
{
  "mainnet": {
    "chainIdDecimal": 1110,
    "chainIdHex": "0x456",
    "name": "GRX Chain",
    "currency": { "name": "GRX", "symbol": "GRX", "decimals": 18 },
    "rpc": ["https://rpc.grxchain.io"],
    "explorers": [{ "name": "GRXscan", "url": "https://grxscan.io" }],
    "contracts": {
      "multicall": "0x2cd9E100Ca0d883A00eC8Ce635EbD4C17508FE3B",
      "wgrx": "0x45C7287F897B3A79Cd3f6e4F14B4CE568f023bD5",
      "grxswapFactory": "0xc7316818841f355c5107753A3f3FDEA799BD25f6",
      "grxswapRouterV2": "0x28fC93b8a20570f2B59d5CA9f8a1dA02C4DBcDF5",
      "pairInitCodeHash": "0xb23d9a8f0a03ecd8f95e43ab1025c71bb79f1cb7128d40546417bfb4b2a74d9c"
    }
  },
  "testnet": {
    "chainIdDecimal": 2507,
    "chainIdHex": "0x9CB",
    "name": "GRX Chain Testnet",
    "currency": { "name": "GRX", "symbol": "GRX", "decimals": 18 },
    "rpc": ["https://testnet.grxchain.io"],
    "explorers": [{ "name": "GRXscan Testnet", "url": "https://testnet.grxscan.io" }],
    "faucet": "https://faucet.grxchain.io"
  }
}
```

### Standards Matrix

| Standard           | Support | Notes                                                       |
| ------------------ | ------- | ----------------------------------------------------------- |
| ERC-20             | ✅       | WGRX conforms; decimals 18                                  |
| ERC-2612 Permit    | ✅/TBD   | Confirm if enabled for WGRX; publish domain separator if so |
| ERC-165            | ✅       | Interface detection for applicable contracts                |
| ERC-2771 (Meta-tx) | ⬜       | Planned/optional                                            |
| EIP-1559           | ⬜       | Legacy gas today; 1559 subject to governance                |

### Event Indexing & Reorg Safety

* Index logs in **block windows** (e.g., 2,000-block chunks).
* Maintain a **12-block reorg buffer**; reprocess recent blocks.
* On WS disconnects, resume from the **last confirmed block**.

### Multicall Guidance

* Use Multicall (`0x2cd9E100…FE3B`) for batched reads.
* Keep batches < **100 calls** or < **500k gas** per aggregate to avoid timeouts.

### Security & Support

* **Official channels only:** trust addresses/URLs listed on the Official Channels page.
* **Public RPCs:** best-effort; run your own nodes or use a provider for production.
* **Hardware wallets:** keep firmware/apps up to date; verify recipient addresses on-device.
* **Bug bounty / disclosures:** (link if available) — respond to security@ with PGP if you publish a key.

### Status & Changelog

* **Status:** `https://status.grxchain.io` (outages, maintenance, incident notes)
* **Changelog:** publish API/RPC/Explorer updates, contract upgrades, and breaking changes.
* **Policy:** aim for **14 days’ notice** before public endpoint deprecations unless urgent security fixes are required.

#### Attribution

* **GRX Chain** and portals are owned/operated by **GRXCHAIN Inc. (BVI)**.
* **GroveX exchange** is operated by **GroveX Pty Ltd (AU)**.
* **WGRX** mainnet contract: `0x45C7287F897B3A79Cd3f6e4F14B4CE568f023bD5`.