Jonathan James Castillo
Product Designer | UX Engineer
Today
I'm a product designer and UX engineer. I move fluidly between design and code, so the work I ship feels like one continuous thought instead of a handoff. I care about clarity, systems thinking, and building interfaces that hold up under real product pressure.
Currently designing and building at Brandcave. Previously, I led design for a top-11 national homebuilder, shaped Workday-partner data migration tools, and contributed to a real-estate investment platform that scaled to 70K+ users.
Case Studies
SysticsTurning cryptic Workday migration errors into a guided resolution workflow
Oakwood HomesLifting Find Your Home completion by 31pp for a Top-11 U.S. homebuilder
Security & Compliance PlatformReplacing a dense compliance list view with a scannable Kanban board
Money Lending PlatformShipping an investor-ready hard-money lending platform on an MVP timeline
Robinland (acquired by ARK7)Scaling a Web3 real-estate platform from 0 to 70K+ users — acquired by ARK7
NorthComing soonDesigning a conversion-focused platform for a quantitative investing brand
Library
Contact
The best way to reach me is by email. You can also view my resume.