Full-Stack Blockchain Developer - Part-time - Worldwide

Full-Stack Crypto Developer (Cryptofolio)

We’re looking for a highly skilled full-stack developer to take over and complete our crypto portfolio tracking app, Cryptofolio. The project is partially built, and we need someone who can step in quickly, understand the existing codebase, and bring the product to launch.

Cryptofolio is a next-generation crypto portfolio tracker that connects exchanges, wallets, and DeFi protocols to calculate the most accurate historical PnL in the industry. Our UI/UX is fully designed, and most components are already built — what we need now is someone who can finish the logic, integrations, and backend.

Responsibilities

• Complete and refine the React Native mobile app
• Implement remaining wallet and exchange integrations (Binance, Coinbase, MetaMask, Phantom, etc.)
• Build and refine backend logic for transaction binding, cost basis calculations, and PnL accuracy
• Integrate on-chain data providers (Moralis, Covalent, Noves, etc.)
• Sync CEX and DeFi transactions smoothly and reliably
• Implement secure user authentication and cloud infrastructure
• Debug, improve performance, and prepare the app for launch
• Work directly with founders and designer for polished delivery

Requirements

Strong experience with:

• React Native
• Node.js or Python backend
• Web3.js / ethers.js / Solana Web3
• CEX APIs + on-chain data
• Deep understanding of crypto transactions: swaps, trades, LP, rewards, bridging, staking
• Ability to reconstruct historical cost basis and PnL
• Clean coding practices and ability to work independently
• Strong debugging and architectural skills

Nice-to-Have

• Experience with portfolio or tax tools (Zerion, Zapper, Koinly, DeBank)
• Background in transaction classification
• Familiarity with AWS/GCP
• Prior fintech or analytics app experience