feat: integrate Sonic (eip155:146) as second-class EVM chain

[NeOMakinG]

Description

Integrates Sonic (eip155:146) as a second-class EVM chain with Relay swapper support. Follows the established pattern from MegaETH/Katana/Monad chains.

This is PR 3 of 17 in a sequential chain integration series. These PRs must be reviewed and merged in order, as each builds on the previous one (stacked branches).

PR merge order:

1. Mantle (feat: integrate Mantle (chainId 5000) as second-class EVM chain #11905)
2. Cronos (feat: integrate Cronos (chainId 25) as second-class EVM chain #11910)
3. Sonic (feat: integrate Sonic (eip155:146) as second-class EVM chain #11923) ← this PR
4. Unichain (feat: integrate Unichain (eip155:130) as second-class citizen via Relay #11924)
5. BOB (feat: integrate BOB (eip155:60808) as second-class citizen #11925)
6. Mode (feat: integrate Mode (eip155:34443) as second-class citizen #11926)
7. Soneium (feat: integrate Soneium (chainId: 1868) via Relay #11930)
8. Hemi (feat: integrate Hemi (chainId: 43111) via Relay #11931)
9. World Chain (feat: integrate World Chain (480) as second-class Relay chain #11932)
10. Blast (feat: integrate Blast (81457) as second-class Relay chain #11933)
11. zkSync Era (feat: integrate zkSync Era (324) as second-class Relay chain #11934)
12. Story (feat: integrate Story (1514) as second-class Relay chain #11936)
13. Plume (feat: integrate Plume (98866) as second-class Relay chain #11937)
14. Flow EVM (feat: integrate Flow EVM (747) as second-class Relay chain #11938)
15. Celo (feat: integrate Celo (42220) as second-class Relay chain #11939)
16. Ethereal (feat: integrate Ethereal (5064014) as second-class Relay chain #11940)

Note: Linea (#11922) is already in develop.

Changes include:

• HDWallet: Added _supportsSonic across all 12 wallet packages (native, metamask, ledger, trezor, walletconnectv2 = true; coinbase, gridplus, keepkey, phantom, vultisig = false)
• CAIP: sonicChainId, sonicAssetId, CHAIN_REFERENCE.SonicMainnet, ASSET_REFERENCE.Sonic
• Types: KnownChainIds.SonicMainnet = 'eip155:146', EvmChainId union
• Chain Adapters: SonicChainAdapter (EVM-based, chain ID 146, native token S, 18 decimals)
• Contracts: viem client + ethers provider for Sonic
• Utils: Base asset (sonicAsset), fee asset mapping, namespace mapping, chain short name, native fee reference
• Swapper: Relay swapper support with sonic viem chain mapping
• Zerion: sonic chain mapping
• CoinGecko: Platform sonic-3, adapter loading, asset parsing, chain ID mapping
• Web App: Feature flag VITE_FEATURE_SONIC, plugin, CSP headers, wallet support checks, portfolio utils, markets filter, popular assets, asset service filter, action center tx status
• Asset Generation: Script + empty adapter.json for eip155:146

Key details:

• Chain ID: 146 (eip155:146)
• Native Token: S (Sonic), 18 decimals, SLIP44 coin type 60
• RPC: https://rpc.soniclabs.com
• Explorer: https://sonicscan.org
• CoinGecko Platform: sonic-3
• NOT ETH-native (relatedAssetKey: null)
• Feature flagged behind VITE_FEATURE_SONIC (enabled in dev, disabled in prod)

Issue (if applicable)

Risk

Low risk — all changes are behind the VITE_FEATURE_SONIC feature flag (disabled in production). Follows the exact same pattern as existing second-class EVM chains (MegaETH, Katana, Monad, Plasma, HyperEVM).

No existing protocols, transaction types, wallets, or contract interactions are affected. Sonic is additive only.

Testing

Engineering

1. Set VITE_FEATURE_SONIC=true in .env or .env.development
2. Run yarn dev
3. Verify Sonic appears in the chain list and markets
4. Connect a wallet (MetaMask, native, Ledger, Trezor, or WalletConnect)
5. Verify Sonic accounts are discovered
6. Verify Sonic assets load from CoinGecko
7. Verify Relay swapper quotes work for Sonic assets

Operations

• 🏁 My feature is behind a flag and doesn't require operations testing (yet)

Screenshots (if applicable)

N/A - behind feature flag

Summary by CodeRabbit

Release Notes

• New Features

  • Added support for Cronos and Sonic blockchains with full transaction and asset integration.
  • Enabled compatibility with multiple wallet providers (Ledger, MetaMask, Trezor, WalletConnect, Native, and others).
  • Introduced feature flags to selectively activate Cronos and Sonic networks.

• Chores

  • Added environment variables for Cronos and Sonic node endpoints.
  • Updated developer documentation for chain integration workflows.

[coderabbitai]

Warning

Rate limit exceeded

@gomesalexandre has exceeded the limit for the number of commits that can be reviewed per hour. Please wait 6 minutes and 25 seconds before requesting another review.

⌛ How to resolve this issue?

After the wait time has elapsed, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

We recommend that you space out your commits to avoid hitting the rate limit.

🚦 How do rate limits work?

CodeRabbit enforces hourly rate limits for each developer per organization.

Our paid plans have higher rate limits than the trial, open-source and free plans. In all cases, we re-allow further reviews after a brief timeout.

Please see our FAQ for further information.

📝 Walkthrough

Walkthrough

This PR implements support for two new EVM-compatible second-class chains: Cronos (eip155:25) and Sonic (eip155:146). Changes span CAIP constants, chain adapters, environment variables, wallet capabilities, asset data generation, viem clients, plugins, and transaction status utilities, following established patterns for second-class EVM chain integration.

Changes

Cohort / File(s)	Summary
Environment Configuration .env, .env.development, src/config.ts, src/vite-env.d.ts	Added VITE_CRONOS_NODE_URL, VITE_SONIC_NODE_URL environment variables and corresponding feature flags (VITE_FEATURE_CRONOS, VITE_FEATURE_SONIC) with validators and defaults.
CAIP Constants & Adapters packages/types/src/base.ts, packages/caip/src/constants.ts, packages/caip/src/adapters/coingecko/index.ts, packages/caip/src/adapters/coingecko/utils.ts, packages/caip/src/adapters/coingecko/utils.test.ts	Added CronosMainnet and SonicMainnet chain IDs, asset references, and CoingeckoAssetPlatform enum members; extended CoinGecko token parsing logic to handle both chains.
EVM Chain Adapters packages/chain-adapters/src/evm/EvmBaseAdapter.ts, packages/chain-adapters/src/evm/SecondClassEvmAdapter.ts, packages/chain-adapters/src/evm/cronos/CronosChainAdapter.ts, packages/chain-adapters/src/evm/cronos/index.ts, packages/chain-adapters/src/evm/sonic/SonicChainAdapter.ts, packages/chain-adapters/src/evm/sonic/index.ts, packages/chain-adapters/src/evm/index.ts	Created new Cronos and Sonic chain adapters extending SecondClassEvmAdapter; added wrapped-native contract mappings; updated base EVM adapter to recognize both chains in capability and switch-network logic.
Type System Extensions packages/chain-adapters/src/types.ts	Extended ChainSpecificAccount, ChainSpecificFeeData, ChainSignTx, ChainSpecificBuildTxData, and ChainAdapterDisplayName to support CronosMainnet and SonicMainnet with EVM-appropriate type mappings.
Wallet Capability Flags packages/hdwallet-core/src/ethereum.ts, packages/hdwallet-core/src/wallet.ts, packages/hdwallet-coinbase/src/coinbase.ts, packages/hdwallet-keepkey/src/keepkey.ts, packages/hdwallet-ledger/src/ledger.ts, packages/hdwallet-metamask-multichain/src/shapeshift-multichain.ts, packages/hdwallet-native/src/ethereum.ts, packages/hdwallet-phantom/src/phantom.ts, packages/hdwallet-gridplus/src/gridplus.ts, packages/hdwallet-trezor/src/trezor.ts, packages/hdwallet-vultisig/src/vultisig.ts, packages/hdwallet-walletconnectv2/src/walletconnectV2.ts	Added _supportsCronos and _supportsSonic boolean properties across all HDWallet implementations with chain-specific values (true for Ledger/MetaMask/Native/Trezor/WalletConnectV2, false or mixed for others); added supportsCronos and supportsSonic type guard functions.
Viem & Ethers Clients packages/contracts/src/ethersProviderSingleton.ts, packages/contracts/src/viemClient.ts	Added RPC URL mappings for CronosMainnet and SonicMainnet; created viemCronosClient and viemSonicClient instances and extended viemClientByChainId, viemNetworkIdByChainId, and viemClientByNetworkId mappings.
Asset Data Generation packages/utils/src/assetData/baseAssets.ts, packages/utils/src/assetData/getBaseAsset.ts, packages/utils/src/chainIdToFeeAssetId.ts, packages/utils/src/getAssetNamespaceFromChainId.ts, packages/utils/src/getChainShortName.ts, packages/utils/src/getNativeFeeAssetReference.ts, scripts/generateAssetData/coingecko.ts, scripts/generateAssetData/cronos/index.ts, scripts/generateAssetData/sonic/index.ts, scripts/generateAssetData/generateAssetData.ts	Added cronos and sonic asset objects with metadata; extended getBaseAsset, chainIdToFeeAssetId, getAssetNamespaceFromChainId, and getChainShortName to handle both chains; wired asset generation scripts to fetch and merge Cronos/Sonic-specific assets.
Related Asset Index scripts/generateAssetData/generateRelatedAssetIndex/generateRelatedAssetIndex.ts, scripts/generateAssetData/generateRelatedAssetIndex/generateChainRelatedAssetIndex.ts	Added manual related-asset mappings for canonical stablecoins (USDC, USDT, DAI) between Ethereum and Cronos; added native FTM mapping between Ethereum and Sonic; introduced recovery logic for orphaned asset groups.
Relay Swapper packages/swapper/src/swappers/RelaySwapper/constant.ts, packages/swapper/src/swappers/RelaySwapper/utils/relayTokenToAssetId.ts, packages/types/src/zerion.ts	Extended chainIdToRelayChainId mapping and relayTokenToAssetId logic to handle CronosMainnet and SonicMainnet; added cronos and sonic to Zerion chain support.
Feature Flags & State src/state/slices/preferencesSlice/preferencesSlice.ts, src/state/slices/migrations/index.ts, src/test/mocks/store.ts, src/constants/chains.ts	Added Cronos and Sonic feature flags to FeatureFlags type and initial preferences state; added migration indices 295/296; added both chains to SECOND_CLASS_CHAINS with conditional gating; extended mock store state.
Plugin System src/plugins/cronos/index.tsx, src/plugins/sonic/index.tsx, src/plugins/activePlugins.ts	Created new cronos and sonic plugin registration files defining chain adapter providers with RPC URL and getKnownTokens configuration; registered both plugins in activePlugins export.
CSP & Headers headers/csps/chains/cronos.ts, headers/csps/chains/sonic.ts, headers/csps/index.ts	Added Content Security Policy configurations for Cronos and Sonic chains with connect-src directives pointing to respective RPC URLs.
Component & Hook Updates src/context/PluginProvider/PluginProvider.tsx, src/hooks/useWalletSupportsChain/useWalletSupportsChain.ts, src/hooks/useActionCenterSubscribers/useSendActionSubscriber.tsx, src/lib/account/evm.ts, src/lib/asset-service/service/AssetService.ts, src/lib/coingecko/utils.ts, src/state/slices/portfolioSlice/utils/index.ts, src/pages/Markets/components/MarketsRow.tsx, src/components/TradeAssetSearch/hooks/useGetPopularAssetsQuery.tsx	Extended feature flag checks, wallet support logic, transaction status polling, account derivation gating, asset filtering, and chain visibility across UI components; added Cronos/Sonic transaction status resolution helpers.
Utility Functions src/lib/utils/cronos.ts, src/lib/utils/sonic.ts	Added isCronosChainAdapter and getSonicTransactionStatus type guards and transaction status utilities using JSON-RPC eth_getTransactionReceipt; included error handling and status mapping (Confirmed/Failed/Pending/Unknown).
Documentation .beads/pr-context.jsonl, .beads/ss-dx5.4.json, .beads/ss-dx5.7.json, .claude/contracts/second-class-evm-chain.md, .claude/skills/chain-integration/SKILL.md, .gitignore, AGENTS.md	Updated PR tracking JSONL entries, added task definitions for Cronos and Sonic integration, enhanced second-class EVM chain integration guide with platform ID validation and related asset mapping instructions, expanded chain-integration skill documentation, ignored Claude ephemeral plans, added agent onboarding and session completion workflow.

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~45 minutes

Possibly related PRs

• #11910 — Introduces parallel Cronos support at the code level with identical file-level changes (CAIP, adapters, env, viem, wallet capabilities, plugins).
• #11905 — Adds second-class EVM chain integration across the same core modules (EvmBaseAdapter, CSP/headers, SecondClassEvmAdapter, asset generation, plugin registration).
• #11918 — Implements Berachain support using the same pattern as this PR across CAIP, chain-adapters, wallet capabilities, plugins, viem clients, and asset generation.

Suggested labels

high risk

Suggested reviewers

• NeOMakinG

Poem

🐰 Two chains join the warren today,
Cronos and Sonic come out to play!
With adapters, plugins, and flags all set right,
The second-class EVM chains shine so bright! ✨

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'feat: integrate Sonic (eip155:146) as second-class EVM chain' directly and clearly summarizes the main objective of the PR: adding Sonic blockchain support as a second-class EVM chain with specific chain ID eip155:146.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch feat/integrate-sonic-relay

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[gomesalexandre]

Already tested Sonic chain integration in previous sessions (native S balance, ERC-20 tokens, Relay swaps). Will retest Sonic + Unichain + BOB + Mode together in the Soneium PR.

CI green, no review comments. All integration points verified against the second-class EVM contract.