Senior Smart Contract Developer – Pet360

Location: Remote (Worldwide)
Employment Type: Contract

About the Role

We are looking for a Senior Smart Contract Developer to join our team at Pet360.

Pet360 is the first blockchain-based pet ecosystem in Brazil. With 160 million pets and a $60 billion market, we see a massive opportunity to transform pet care through Web3 technology.

Our Web2 platform is 75% complete. We are now building the Web3 layer from scratch — pet NFT passports, vaccine certificates, smart contract adoptions, and on-chain pet insurance.

What You Will Do

Write and deploy Solidity smart contracts (ERC-721 for pet passports, ERC-1155 for vaccine certificates)

Implement upgradeable contract patterns (UUPS) for future flexibility

Write comprehensive tests using Foundry or Hardhat

Optimize gas usage and ensure security best practices

Design the on-chain architecture for pet identity, vaccine verification, and insurance claims

Work alongside our backend and frontend teams

What We Are Looking For

3+ years of software development experience

1+ year of Solidity and EVM development

Strong understanding of ERC-721 and ERC-1155 standards

Experience with Foundry or Hardhat

Understanding of smart contract security and gas optimization

Experience with upgradeable contract patterns (UUPS or Transparent proxies)

Professional English proficiency

Nice to have:

Experience with multi-chain deployments (Polygon, Ethereum, BSC)

Experience with smart contract auditing

Experience with IPFS and decentralized storage

Experience with AI-assisted development (Cursor, Claude Code)

What We Offer

Fully remote — work from anywhere in the world

Contract with long-term growth potential

Opportunity to convert to a full-time role after the first 2 or 3 months

30+ hours per week

Competitive hourly rate ($70-120 per hour, negotiable)

Founding team token allocation

Payment in crypto (USDC/USDT) or fiat (Wise/PayPal) – your preference

About Us

Block Sherpa is a Web3-native consulting and development firm based in London, UK. We help startups and enterprises build cutting-edge blockchain solutions. Our team is fully remote, crypto-native.

How to Apply:

Send your resume and GitHub/LinkedIn to: hello@blockcsherpa.dev

Subject: Smart Contract Developer – Pet360(cryptoTask)