---
name: megaeth-developer-f57576e053ff
description: End-to-end MegaETH development playbook (Feb 2026). Covers wallet operations, token swaps (Kyber Network), eth_sendRawTransactionSync (EIP-7966) for instant receipts, JSON-RPC batching, real-time mini-block subscriptions, storage-aware contract patterns (Solady RedBlackTreeLib), MegaEVM gas model, WebSocket keepalive, bridging from Ethereum, and debugging with mega-evme. Use when building on MegaETH, managing wallets, sending transactions, or deploying contracts.
---

# MegaETH Development Skill

## What this Skill is for
Use this Skill when the user asks for:
- 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 (avoiding expensive SSTORE costs)
- Gas estimation and fee configuration
- Testing and debugging MegaETH transactions
- WebSocket subscriptions and mini-block streaming
- Bridging ETH from Ethereum to MegaETH

## 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`

### 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 gas after block.timestamp access)

### 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)
- Wallet operations: [wallet-operations.md](wallet-operations.md)
- Frontend patterns: [frontend-patterns.md](frontend-patterns.md)
- RPC methods reference: [rpc-methods.md](rpc-methods.md)
- Smart contract patterns: [smart-contracts.md](smart-contracts.md)
- Storage optimization: [storage-optimization.md](storage-optimization.md)
- Gas model: [gas-model.md](gas-model.md)
- Testing & debugging: [testing.md](testing.md)
- Security considerations: [security.md](security.md)
- Reference links: [resources.md](resources.md)


---
Source attribution: modbender
Original project: https://github.com/modbender/skill-library-mcp/blob/d9c8fe903b5b4e82237dbe8d0df8567783022e18/data/megaeth/SKILL.md
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Mega AI Hub.

## Upstream license notice

MIT License

Copyright (c) 2025 skill-library-mcp contributors

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.



# Mega AI Hub resource metadata

Creator / publisher: modbender
Original project: https://github.com/modbender/skill-library-mcp/blob/d9c8fe903b5b4e82237dbe8d0df8567783022e18/data/megaeth/SKILL.md
Attribution basis: Source repository record

Fields of work: Development & Engineering, Product Management
Roles: Backend Developer, Data Engineer, DevOps / SRE, Growth Product Manager, Product Manager
Specialties: API, Backend
Tools: Kyber Network, Megaeth
Country applicability: Country not specified
Classification basis: Source catalog labels
Instruction SHA-256: b096967b69eebe8aacbbbd586e8e70815224742c75868f7183d0208d4786cd0d