megaeth-developer

MegaETH Development Skill What this Skill is for Use this Skill when the user asks for: Foundry project setup targeting MegaETH Writing and running tests (unit, fuzz, invariant) on MegaETH Deploying and verifying contracts on MegaETH Wallet setup and management on MegaETH Sending transactions, checking balances, token operations Token swaps via Kyber Network aggregator MegaETH dApp frontend (React / Next.js with real-time updates) RPC configuration and transaction flow optimization Smart contract development with MegaEVM considerations Storage optimization (transient storage, Solady patterns) Gas estimation and fee configuration Testing and debugging MegaETH transactions WebSocket subscriptions and mini-block streaming Bridging ETH from Ethereum to MegaETH Privy integration for headless/automated signing Meridian / x402 payments on MegaETH Ultra-low latency transaction patterns ERC-7710 delegations (scoped permissions, spending limits, redelegation chains) MetaMask Smart Accounts (ERC-4337 accounts, signers, user operations) Advanced permissions (ERC-7715) via MetaMask MegaNames (.mega naming service) — registration, resolution, subdomains, subdomain marketplace, text records Chain Configuration Network Chain ID RPC Explorer Mainnet 4326 https://mainnet.megaeth.com/rpc https://mega.etherscan.io Testnet 6343 https://carrot.megaeth.com/rpc https://megaeth-testnet-v2.blockscout.com Default stack decisions (opinionated) 1. Transaction submission: eth_sendRawTransactionSync first Use eth_sendRawTransactionSync (EIP-7966) — returns receipt in <10ms Eliminates polling for eth_getTransactionReceipt Docs: https://docs.megaeth.com/realtime-api 2. RPC: Multicall for eth_call batching (v2.0.14+) Prefer Multicall ( aggregate3 ) for batching multiple eth_call requests As of v2.0.14, eth_call is 2-10x faster; Multicall amortizes per-RPC overhead Still avoid mixing slow methods ( eth_getLogs ) with fast ones in same request Note: Earlier guidance recommended JSON-RPC batching over Multicall for caching benefits. With v2.0.14's performance improvements, Multicall is now preferred. 3. WebSocket: keepalive required Send eth_chainId every 30 seconds 50 connections per VIP endpoint, 10 subscriptions per connection Use miniBlocks subscription for real-time data 4. Storage: slot reuse patterns SSTORE 0→non-zero costs 2M gas × multiplier (expensive) Use Solady's RedBlackTreeLib instead of Solidity mappings Design for slot reuse, not constant allocation 5. Gas: skip estimation when possible Base fee stable at 0.001 gwei, no EIP-1559 adjustment Ignore eth_maxPriorityFeePerGas (returns 0) Hardcode gas limits to save round-trip Always use remote eth_estimateGas (MegaEVM costs differ from standard EVM) 6. Debugging: mega-evme CLI Replay transactions with full traces Profile gas by opcode https://github.com/megaeth-labs/mega-evm Operating procedure 1. Classify the task layer Frontend/WebSocket layer RPC/transaction layer Smart contract layer Testing/debugging layer 2. Pick the right patterns Frontend: single WebSocket → broadcast to users (not per-user connections) Transactions: sign locally → eth_sendRawTransactionSync → done Contracts: check SSTORE patterns, avoid volatile data access limits Testing: use mega-evme for replay, Foundry with --skip-simulation Delegations: create scoped permissions → sign → share → redeem via eth_sendRawTransactionSync 3. Implement with MegaETH-specific correctness Always be explicit about: Chain ID (4326 mainnet, 6343 testnet) Gas limit (hardcode when possible) Base fee (0.001 gwei, no buffer) Storage costs (new slots are expensive) Volatile data limits (20M total compute gas cap, retroactive, when block.timestamp accessed) 4. Deliverables expectations When implementing changes, provide: Exact files changed + diffs Commands to build/test/deploy Gas cost notes for storage-heavy operations RPC optimization notes if applicable Progressive disclosure (read when needed) Foundry setup & deploy: foundry-config.md Wallet operations: wallet-operations.md Frontend patterns: frontend-patterns.md Privy integration: privy-integration.md Meridian payments: meridian.md RPC methods reference: rpc-methods.md Smart contract patterns: smart-contracts.md Storage optimization: storage-optimization.md Gas model: gas-model.md Testing & debugging: testing.md Security considerations: security.md ERC-7710 delegations: erc7710-delegations.md MetaMask Smart Accounts: smart-accounts.md Warren Protocol (on-chain websites): warren.md MegaNames (.mega naming): meganames.md Reference links & attribution: resources.md