Skip to main contentJacob D. Castro

About Me

Jacob D. Castro

XIV Systems · Santa Maria, California

me@jacobdcastro.comAugust 2026

Abstract

I'm a 29 year old software engineer living on the Central Coast of California. I live and breathe startups, enjoying the zero-to-one process.

Keywords—full stack engineering, startups, zero to one, DeFi security, self-directed learning

Background

My education has been mostly self-directed via books and online courses, with the exception of my first community college CS101 class in 2015. I took a few years off from tech for personal reasons, and returned in 2018 to continue my code learning journey.

Since then, I've joined multiple early-stage startups in founding engineer roles, including a YCombinator startup, where I learned the ins and outs of the Bay Area tech grind and even spent a short stint living in a founder house, where I fell in love with startups.

Prior Work

This led me to take my first stab at becoming a founder myself, building a product that I found many companies needing at the time. I spent many months building the product with my co-founder, talking to users, and speaking with investors to raise a pre-seed.1

Eventually, I burned through my personal runway and ultimately sunsetted the project.

Current Work

I'm now a Senior Full Stack Engineer at Phylax Systems [1], working in the crypto decentralized finance (DeFi) security space and building a blockchain-based financial security product to protect user funds. I've had the privilege of growing more here than any other company, raising my code quality standards and security best practices; raising the bar in all the ways a security product calls for.

On the side, I'm tinkering with some personalized custom AI workflows [2] to help me ship better code quicker. I also love to read technical books, currently: Designing Data-Intensive Applications [3].

Outside of Work

I enjoy both watching and playing sports, working out, traveling, reading books and spending time with family. Check out my now page [4] to see what I've been up to more recently.

Correspondence

I'm always open to cool connections and opportunities. Feel free to reach out via email, X (fka Twitter) [5], or Telegram [6].

References

  1. Phylax Systems.
  2. J. D. Castro, “AI Agent Workflows.” xiv.sh
  3. M. Kleppmann, Designing Data-Intensive Applications. dataintensive.net
  4. J. D. Castro, “Now.” jacobdcastro.com/now
  5. X (fka Twitter). x.com/jacobdcastro
  6. Telegram. t.me/jacobdcastro

Footnotes

  1. Fun fact: I learned Neovim in a weekend (still learning it) to replace VSCode and save resources on my M1 MacBook so I could run more Docker containers. The config lives at github.com/jacobdcastro/nvim-config. ↩