Remote Web3 Wallet & Token Integration Engineer

TechHavenLabs; Greater London; On-site; GBP 85,000 - 120,000; Full time

Job summary

TechHavenLabs is seeking a Web3 Developer to build foundational blockchain integration infrastructure for the platform on a Next.js-based product. You will implement wallet architecture, transaction flows, deployed-contract integrations, and on-chain application layers, collaborating with FSD and UI teams to ship production-ready Web3 features.

The role focuses on robust wallet state management, token purchases, on-chain data reads, and secure handling of keys and RPCs.

Qualifications

• Strong professional experience with Web3 or blockchain application development.
• Experience configuring Ethereum-compatible networks and smart-contract integration.

Responsibilities

• Replace direct window.ethereum integrations with a structured wallet layer using wagmi and viem.
• Implement wallet connection, disconnection, account switching, and network switching.
• Handle missing wallets, rejected requests, incorrect networks, RPC failures, reverted transactions, and transaction timeouts.
• Build reusable hooks and components for wallet state, contract reads, contract writes, and transaction tracking.
• Complete the platform's token-purchase experience end to end — connect wallet, select network, review transaction, submit, track states, display result.
• Read token balances directly from deployed contracts and replace hardcoded values with on-chain data.
• Connect blockchain transactions with the platform's backend APIs where off-chain records are required.
• Coordinate with the Full-Stack Developer on transaction history, notifications, and database persistence.
• Coordinate with the Frontend Developer to connect wallet and contract functionality to production interfaces.
• Prepare reusable integration patterns for digital payments, NFT minting, marketplace transactions, auctions, token rewards, staking, and blockchain-backed verification.
• Define consistent project patterns for contract hooks, wallet state, transaction lifecycle, error handling, and network configuration.
• Keep private keys, RPC credentials, and sensitive configuration outside the source code.
• Write clear, maintainable, strongly typed TypeScript code.
• Document contract interfaces, deployed addresses, supported networks, and integration decisions.
• Participate in code reviews and technical architecture discussions.

Skills

Web3 development

React

Next.js

TypeScript

Ethereum networks

Wallet integration

Contract reads/writes

Testing

Tools

wagmi

viem

MetaMask integration

EVM networks config

RPC endpoints management

Job description

TechHavenLabs is seeking a Web3 Developer to build foundational blockchain integration infrastructure for the platform on a Next.js-based product. You will implement wallet architecture, transaction flows, deployed-contract integrations, and on-chain application layers, collaborating with FSD and UI teams to ship production-ready Web3 features.

The role focuses on robust wallet state management, token purchases, on-chain data reads, and secure handling of keys and RPCs.