Portfolio
Senior quant engineer and full-stack builder — agent-friendly platforms, crisp interfaces, and production habits from two decades in finance tech.
I build data-heavy products end to end: from schema and APIs to dashboards people enjoy using. This site is a living notebook — case studies, writing, and experiments.
Tech stack
Pulled from project frontmatter — a snapshot of what shows up in shipped work.
Typed stacks, predictable deploys, and UI that stays coherent as requirements move.
Small milestones, visible progress, and room to adjust when the brief evolves.
Based in New York; comfortable collaborating across US and European hours.
Case studies
An agentic AI platform that turns a story concept into illustrated, print-ready books — scene authoring, illustration, multi-model grading, PDF assembly, and promo pages, orchestrated end to end.
From the desk
When programming gets 10–50x cheaper, layers disappear, technical debt reprices, throwaway UIs become rational, and implementation moats evaporate — while network effects and domain expertise survive.
L1 through L5 for agents, the factory-floor parallel, which cognitive work is already automated, and what remains when humans become observers rather than operators.
On mentorship, atrophy, and what happens when the world's greatest generalist is available to everyone, always.
Testimonials
“It was a pleasure working with Joel at GS where he was a hiring mgr for Associate and VP level quants. As a recruiter, I appreciated his partnership with my team and focus on our recruitment efforts.…”
Christine Hayes Quigley
Talent Acquisition · Recruiting · Learning and Development · HR Program Manager & HR Project Manager
“I know Joel Horowitz as a Vice President at Goldman Sachs. He is the hiring manager for a heavy recruitment effort that aimed to hire several VPs and associates. He works extremely well with the HR…”
Velizar Milchev
Licensed Financial Services Professional · Risk Officer · MBA · LLM · Series 4, 7, 9, 10, 63, 65, 66
“Joel's one of the very top quants/structurers I've worked with during my tenure at Goldman Sachs. In addition to world-class fin math skills, he is purely and simply one of the brightest people I've…”
Pierre H. Richemond
Multimodal at Cohere
From concept to creation
Open to selective freelance and collaboration. If you're shipping something ambitious, I'd love to hear the constraints.
Get in touch
