Develop Production-Grade Web3 Applications

This skill turns an AI agent into an expert blockchain developer covering smart contract engineering, DeFi protocol design, NFT platforms, and Web3 application architecture across multiple ecosystems. It writes and audits smart contracts in Solidity (proxy contracts, diamond standard, factory patterns), Rust (Solana, NEAR, Cosmos), and Vyper, using OpenZeppelin libraries and upgradeable patterns like transparent, UUPS, and beacon proxies. It applies formal verification tools such as Certora, Slither, and Mythril, and designs multi-signature wallets and governance contracts.

Beyond Ethereum - where it works with Web3.js, Ethers.js, and Viem across Layer 2s like Polygon, Arbitrum, Optimism, Base, and zkSync, and implements EIPs including ERC-20, ERC-721, ERC-1155, and ERC-4337 account abstraction - it also builds on Solana with Anchor, Cosmos SDK, Polkadot/Substrate, NEAR, Cardano Plutus, Algorand PyTeal, Hyperledger Fabric, and Bitcoin Lightning/Taproot.

For DeFi, it designs AMMs (Uniswap V2/V3, Curve, Balancer), lending protocols (Compound, Aave, MakerDAO), yield farming, flash loans, and synthetic asset protocols backed by oracle integrations. For NFTs, it handles ERC-721/1155 marketplaces, royalty standards (EIP-2981), fractional ownership, and IPFS-backed metadata storage. On the frontend, it wires up wallet connections (MetaMask, WalletConnect, Coinbase Wallet) through React/Next.js with Wagmi and RainbowKit, including gasless meta-transactions and decentralized identity flows.

Use it for blockchain and Web3 development tasks: smart contract implementation and auditing, DeFi protocol architecture, NFT platform builds, cross-chain bridge design, tokenomics modeling, or enterprise blockchain integration such as supply chain tracking, KYC/AML compliance, CBDC, or asset tokenization. Do not use it for tasks unrelated to blockchain development or that need a different domain or tool entirely.

Given a set of goals, constraints, and required inputs, it produces: a system architecture weighing security, scalability, and decentralization trade-offs; production-ready contract code with security measures and fuzzing/property-based tests; gas optimization and transaction cost analysis; regulatory compliance considerations; audit-ready documentation; monitoring and analytics setup for on-chain application performance; and a security assessment covering attack vectors and mitigations. For deeper implementation detail it references a companion implementation-playbook resource.

Local dev and deployment tooling (Hardhat, Foundry, Ganache), on-chain indexing via The Graph Protocol, RPC node management, IPFS pinning services, oracle networks (Chainlink price feeds and VRF, API3, Band Protocol, Pyth Network), and wallet SDKs (MetaMask, WalletConnect, Coinbase Wallet).

Web3 and smart contract developers, DeFi protocol teams, NFT platform builders, blockchain security auditors, and enterprises integrating tokenization, CBDC, or supply-chain tracking into permissioned or public chains. It fits teams that need to weigh MEV protection, economic security, and game-theoretic incentive design alongside code, not just ship a contract - and that value formal verification and property-based testing over rapid, unaudited deployment. Tokenomics work is also in scope: vesting schedules, bonding curves, staking-reward distribution, and protocol-owned liquidity design for governance tokens and DAO treasuries.