From 17c8117fb774a8b42187728324b1296baa2b92a3 Mon Sep 17 00:00:00 2001
From: Natalie Bunduwongse <nf1993@gmail.com>
Date: Mon, 2 Feb 2026 15:55:38 +1300
Subject: [PATCH] feat(wallet): add Ethereum Sepolia Testnet configuration

---
 packages/wallet/src/constants.ts              |  3 ++
 packages/wallet/src/index.ts                  |  4 +++
 .../wallet/src/network/chainRegistry.test.ts  | 14 ++++-----
 packages/wallet/src/network/chainRegistry.ts  |  4 +--
 packages/wallet/src/network/presets.ts        | 31 +++++++++++++++++++
 5 files changed, 47 insertions(+), 9 deletions(-)

diff --git a/packages/wallet/src/constants.ts b/packages/wallet/src/constants.ts
index 388732887d..1054a7d2f3 100644
--- a/packages/wallet/src/constants.ts
+++ b/packages/wallet/src/constants.ts
@@ -18,6 +18,9 @@ export const ARBITRUM_ONE_CHAIN_ID = 42161;
 /** Arbitrum Sepolia Testnet chain ID */
 export const ARBITRUM_SEPOLIA_CHAIN_ID = 421614;
 
+/** Ethereum Sepolia Testnet chain ID */
+export const ETHEREUM_SEPOLIA_CHAIN_ID = 11155111;
+
 /**
  * Magic configuration for Immutable networks
  * @internal
diff --git a/packages/wallet/src/index.ts b/packages/wallet/src/index.ts
index 8e11096aca..48bdee609b 100644
--- a/packages/wallet/src/index.ts
+++ b/packages/wallet/src/index.ts
@@ -7,6 +7,7 @@ export {
   IMMUTABLE_ZKEVM_TESTNET_CHAIN_ID,
   ARBITRUM_ONE_CHAIN_ID,
   ARBITRUM_SEPOLIA_CHAIN_ID,
+  ETHEREUM_SEPOLIA_CHAIN_ID,
 } from './constants';
 
 // Export presets (public API)
@@ -23,6 +24,9 @@ export {
   ARBITRUM_SEPOLIA,
   ARBITRUM_ONE_CHAIN,
   ARBITRUM_SEPOLIA_CHAIN,
+  // Ethereum chains
+  ETHEREUM_SEPOLIA,
+  ETHEREUM_SEPOLIA_CHAIN,
 } from './network/presets';
 
 // Export chain registry for looking up chain configs
diff --git a/packages/wallet/src/network/chainRegistry.test.ts b/packages/wallet/src/network/chainRegistry.test.ts
index 7a75e1bace..004bc7b90f 100644
--- a/packages/wallet/src/network/chainRegistry.test.ts
+++ b/packages/wallet/src/network/chainRegistry.test.ts
@@ -1,7 +1,7 @@
 import { Environment } from '@imtbl/config';
 import { getChainConfig, getEvmChainFromChainId } from './chainRegistry';
 import { EvmChain } from '../types';
-import { ARBITRUM_ONE_CHAIN, ARBITRUM_SEPOLIA_CHAIN } from './presets';
+import { ARBITRUM_ONE_CHAIN, ETHEREUM_SEPOLIA_CHAIN } from './presets';
 
 describe('chainRegistry', () => {
   describe('getChainConfig', () => {
@@ -13,12 +13,12 @@ describe('chainRegistry', () => {
       expect(config.name).toBe('Arbitrum One');
     });
 
-    it('returns Arbitrum Sepolia config for SANDBOX', () => {
+    it('returns Ethereum Sepolia config for SANDBOX', () => {
       const config = getChainConfig(EvmChain.ARBITRUM_ONE, Environment.SANDBOX);
 
-      expect(config).toEqual(ARBITRUM_SEPOLIA_CHAIN);
-      expect(config.chainId).toBe(421614);
-      expect(config.name).toBe('Arbitrum Sepolia');
+      expect(config).toEqual(ETHEREUM_SEPOLIA_CHAIN);
+      expect(config.chainId).toBe(11155111);
+      expect(config.name).toBe('Ethereum Sepolia');
     });
 
     it('throws error for unsupported chain', () => {
@@ -45,8 +45,8 @@ describe('chainRegistry', () => {
       expect(getEvmChainFromChainId(42161)).toBe(EvmChain.ARBITRUM_ONE);
     });
 
-    it('returns ARBITRUM_ONE for Arbitrum Sepolia chainId', () => {
-      expect(getEvmChainFromChainId(421614)).toBe(EvmChain.ARBITRUM_ONE);
+    it('returns ARBITRUM_ONE for Ethereum Sepolia chainId', () => {
+      expect(getEvmChainFromChainId(11155111)).toBe(EvmChain.ARBITRUM_ONE);
     });
 
     it('handles string chainId', () => {
diff --git a/packages/wallet/src/network/chainRegistry.ts b/packages/wallet/src/network/chainRegistry.ts
index 04899fd84a..48eae8aa98 100644
--- a/packages/wallet/src/network/chainRegistry.ts
+++ b/packages/wallet/src/network/chainRegistry.ts
@@ -4,7 +4,7 @@ import {
   IMMUTABLE_ZKEVM_MAINNET_CHAIN,
   IMMUTABLE_ZKEVM_TESTNET_CHAIN,
   ARBITRUM_ONE_CHAIN,
-  ARBITRUM_SEPOLIA_CHAIN,
+  ETHEREUM_SEPOLIA_CHAIN,
 } from './presets';
 import { ChainId } from './chains';
 
@@ -18,7 +18,7 @@ const CHAIN_REGISTRY: Record<EvmChain, Record<Environment, ChainConfig>> = {
   },
   [EvmChain.ARBITRUM_ONE]: {
     [Environment.PRODUCTION]: ARBITRUM_ONE_CHAIN,
-    [Environment.SANDBOX]: ARBITRUM_SEPOLIA_CHAIN,
+    [Environment.SANDBOX]: ETHEREUM_SEPOLIA_CHAIN,
   },
 };
 
diff --git a/packages/wallet/src/network/presets.ts b/packages/wallet/src/network/presets.ts
index e05fe869fb..61bcec505a 100644
--- a/packages/wallet/src/network/presets.ts
+++ b/packages/wallet/src/network/presets.ts
@@ -4,6 +4,7 @@ import {
   IMMUTABLE_ZKEVM_TESTNET_CHAIN_ID,
   ARBITRUM_ONE_CHAIN_ID,
   ARBITRUM_SEPOLIA_CHAIN_ID,
+  ETHEREUM_SEPOLIA_CHAIN_ID,
   MAGIC_CONFIG,
 } from '../constants';
 
@@ -67,6 +68,21 @@ export const ARBITRUM_SEPOLIA_CHAIN: ChainConfig = {
   sequenceIdentityInstrumentEndpoint: 'https://next-identity.sequence-dev.app',
 };
 
+/**
+ * Ethereum Sepolia Testnet chain configuration
+ */
+export const ETHEREUM_SEPOLIA_CHAIN: ChainConfig = {
+  chainId: ETHEREUM_SEPOLIA_CHAIN_ID,
+  name: 'Ethereum Sepolia',
+  rpcUrl: 'https://rpc.sepolia.org',
+  relayerUrl: 'https://next-sepolia-relayer.sequence.app',
+  nodeUrl: 'https://next-nodes.sequence.app/sepolia',
+  apiUrl: 'https://api.sandbox.immutable.com',
+  passportDomain: 'https://passport.sandbox.immutable.com',
+  feeTokenSymbol: 'ETH',
+  sequenceIdentityInstrumentEndpoint: 'https://next-identity.sequence-dev.app',
+};
+
 /**
  * Default chains (testnet + mainnet)
  * Testnet is first (default initial chain)
@@ -152,3 +168,18 @@ export const ARBITRUM_ONE = {
 export const ARBITRUM_SEPOLIA = {
   chains: [ARBITRUM_SEPOLIA_CHAIN],
 };
+
+/**
+ * Ethereum Sepolia testnet only preset
+ *
+ * @example
+ * ```typescript
+ * const provider = await connectWallet({
+ *   ...ETHEREUM_SEPOLIA,
+ *   auth,
+ * });
+ * ```
+ */
+export const ETHEREUM_SEPOLIA = {
+  chains: [ETHEREUM_SEPOLIA_CHAIN],
+};