Web3 product engineering

I build the product layer around blockchain systems: wallets, trading interfaces, token flows, indexers, and the services that sit between a chain and the person using it.

That has meant Ethereum and EVM networks, EOSIO and Antelope, Polygon, Arbitrum, and Flow, and on each of them the contract was a small part of the work next to indexed data, transaction state, signing, and interfaces that show people what they are about to commit to.

I arrived here through financial systems rather than through crypto. Card products at American Express and a mobile bank at Wink set the constraints I still work against: identity, partner integrations, and money movement a person can follow.

Blockchain engineering workshop in Costa Rica

Tokens, protocol state, and infrastructure

At Knowledge I built the ERC-20 token contracts and the serverless AWS services around the 2018 mainnet ICO, plus a React and Web3.js marketplace with a wallet dashboard. At EOS Costa Rica I helped launch the EOS mainnet, operated validators, and built Grant Thornton's private EOSIO chain for intercompany transactions and tax workflows.

Indexing, subscriptions, and browser signing

Bitcash is a peer-to-peer exchange. I built WebAuthn key management and QR signature requests so trades could settle in the browser without an external wallet. ChainGraph grew from that work as an open-source GraphQL path over EOSIO and Antelope data.

Wallets, marketplaces, auctions, and trading

RareMint needed a wallet path into Polygon collectible auctions. I integrated WalletConnect so bidding stayed inside the marketplace instead of bouncing out to a separate wallet flow.

At ZTX I built a WebGL EVM wallet connector on MetaMask, Ethers.js, and a custom JavaScript event system, so signing and NFT trading happened without leaving the world. For Bitlauncher I deployed Gnosis auction contracts to EOS EVM, and the wallet interface showed EVM balances through wagmi subscriptions next to EOS balances polled over RPC. Opyn is a decentralized options protocol on Arbitrum, and I integrated the protocol and its Arbitrum testnet into the trading interface with viem and wagmi.

Writing about Web3 systems

Web3 employment record

The employment record behind this work is the Web3 CV.

Open to direct hire, international hire, or contracting through Blockmatic Labs LLC. Cannot work under W-2. Based in Costa Rica, working US Mountain Time.

Tell me what you're building and where it's stuck. Start a conversation.