Senior Smart Contract Developer - Pet360 (Blockchain, Solidity, EVM)
$70 - $120 per hourAbout the Project
We are building Pet360 — the first blockchain-based pet ecosystem in Brazil. 160 million pets, $60 billion market, zero blockchain infrastructure today.
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.
We are looking for a Senior Smart Contract Developer to join our team.
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
- Contract with long-term growth potential
- 30+ hours per week
- $70-120 per hour (negotiable)
- Founding team token allocation
- Payment in crypto (USDC/USDT) or fiat (Wise/PayPal)
£130k per annum
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