Francisco De Borja Aranda Castillejo
Staff Software Engineer at XMTP Labs
Spain
Summary
🤩
Rockstar🎓
Top SchoolFrancisco De Borja Aranda Castillejo is a Staff Software Engineer based in Spain with 11 years of experience specializing in distributed systems, protocol engineering, and infrastructure. He has progressed from Linux systems administration into senior engineering roles at Red Hat and Chainlink Labs, and now focuses on blockchain and messaging infrastructure at XMTP Labs after a protocol engineering stint at ZetaChain. His open-source contributions include security- and gas-optimized Solidity work on the prominent Chainlink oracle repository, demonstrating a strong practical grasp of smart contracts, reentrancy protection, and on-ramp integrations. Comfortable across backend systems, DevOps, and low-level platform maintenance, he blends pragmatic production reliability with protocol-level thinking. Francisco’s background in large-scale open-source projects and early systems administration gives him an uncommon combination of operational rigor and blockchain protocol expertise.
11 years of coding experience
13 years of employment as a software developer
Tecnico Superior Administración Sistemas Informáticos, Tecnico Superior Administración Sistemas Informáticos at I.E.S Politécnico Jesus MarínUOC (Universitat Oberta de Catalunya)
Spanish, English
Stackoverflow
11reputation
3kreached
0answers
1question
Github Skills (12)
smart-contracts10
openzeppelin10
chainlink10
solidity10
ethereum10
blockchain10
testing9
oracles7
oracle7
go7
assembly6
x86-646
Programming languages (10)
Github contributions (5)
smartcontractkit/chainlink
Jan 2023 - Mar 2024
node of the decentralized oracle network, bridging on and off-chain computation
Role in this project:
Back-end Developer
Back-end DeveloperContributions:36 reviews, 9 PRs, 65 pushes in 1 year 2 months
Contributions summary:Francisco primarily contributed to the smart contract logic within the Chainlink repository. Their work involved configuring and testing new functionalities like `maxCheck` and `maxPerform`, implementing custom error handling, and modifying existing contracts. They demonstrated expertise in Solidity, including using OpenZeppelin contracts, as well as adding support for onRamps. The user also optimized gas usage and implemented reentrancy guards, showing strong attention to security and efficiency.
golangcomputationethereumblockchaindecentralized
smartcontractkit/timelock-worker
Aug 2023 - Sep 2024
Daemon to poll and execute scheduled transactions from a Timelock contract.
Contributions:35 reviews, 32 PRs, 44 pushes in 1 year 1 month
mcmschedulertimelock
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