Megaeth Developer

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.

Security Scan

This is an instruction-only MegaETH development playbook whose files, instructions, and external endpoints are internally consistent with the stated purpose, but some operational recommendations are risky and should be reviewed before use in production.

Purpose & Capability

The name/description (MegaETH developer playbook) matches the content: wallet ops, RPC methods, gas model, WebSocket guidance, contract/storage patterns, testing and debugging. Listed endpoints, tooling (mega-evme, viem, Foundry), and DEX aggregator (Kyber) are appropriate for the stated goal.

Instruction Scope

SKILL.md and supporting files confine instructions to MegaETH development workflows. They do not instruct the agent to read arbitrary host files or request unrelated credentials. However, the guidance includes operational choices that escalate risk if followed blindly (e.g., recommending skipping local simulation, hardcoding gas limits, pre-signing/pipelining transactions, advice to store keys in local JSON files). These are within the developer domain but are safety-sensitive and should be used cautiously.

Install Mechanism

No install spec and no code files to execute are included; this is instruction-only, so nothing is downloaded or written by the skill itself.

Credentials

The skill requests no environment variables, no credentials, and no config paths. External network endpoints (mainnet/testnet RPCs, WebSocket URLs, Kyber aggregator, GitHub repos) are referenced appropriately for a blockchain dev playbook.

Persistence & Privilege

Skill is not always-enabled and has default autonomy settings. It does not request persistent platform-level privileges or attempt to modify other skills or system-wide configs.

Scan Findings in Context

[no_code_files] expected: The regex-based scanner found nothing to analyze because this is an instruction-only skill (SKILL.md + supporting docs). This is expected for a documentation/playbook-style skill.

Assessment

This skill is an in-depth MegaETH developer playbook and appears coherent with that purpose, but treat its operational recommendations as advice — not gospel. Before using in production: 1) Verify the provenance of the network endpoints and GitHub repos (source is unknown). 2) Don't embed private keys in plaintext files or automated scripts; prefer hardware wallets or secure key management. 3) Review risky recommendations (skipping local simulation, hardcoding gas, pre-signing and nonce pipelining) on a testnet and with backups — these speedups can cause lost funds or replay/nonce issues if misused. 4) Confirm contract and bridge addresses independently (explorers or maintainers) before sending value. 5) If you need the skill to run code autonomously, prefer adding explicit safeguards (confirmation prompts, use of hardware wallets, limit of pre-signed txs). If you want higher confidence about origin/authenticity, ask the publisher for provenance or prefer official MegaETH documentation/repos.

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
• Frontend patterns: frontend-patterns.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
• Reference links: resources.md