Benjamin Cohen

Senior Frontend Engineer (AI Governance) @ LangChain | prev. Microsoft

Salt Lake City, Utah, United States

About

Senior Software Engineer with over 10 years of experience split between being a software developer and educating the next generation of developers. I've worked at large orgs (Microsoft, SoFi), startups (Fullstack Academy, DUOS) and non-profits (Code Platoon) and bring strong CS fundamentals and full stack experience with a specialization in frontend technologies - meaning I can guarantee a pixel perfect Figma -> deployed translation in the pre-AI era. My expertise includes TypeScript, React, MUI, ShadCN, Radix, Next.js, Tanstack, and Optimizely, with a strong focus on creating efficient and reliable interfaces using React and its ecosystem. At SoFi, I contribute to building production-level systems while collaborating with designers and product managers to deliver pixel-perfect user experiences. I worked on the student loan refinance funnel and drove A/B testing leading to a ~$12 million increase in MRR. Currently working contract at Mercor as a software development expert helping to train frontier AI models. Most interested currently in working hybrid/in-person with a passionate team building something in the AI or robotics space.

Experience

  • Senior Frontend Engineer (AI Governance) at LangChain
    Jun 2026 - Present · 1 mo

    Working on the frontend for visualizing LLM governance tooling including an LLM Gateway

  • Software Development Expert at Mercor
    Feb 2026 - Present · 5 mos

    Creating rubrics and related metadata for arbitrary software development problems for a frontier AI lab. Essentially I'm the 'human feedback' in a RLHF loop with the goal of increasing the scope and complexity of what an AI can reasonably accomplish in a large codebase.

  • Senior Software Engineer at SoFi
    Dec 2023 - Jul 2025 · 1 yr 8 mos

  • Lead Software Instructor at Code Platoon
    Oct 2022 - Oct 2023 · 1 yr 1 mo

    Taught modern full-stack development at a not-for-profit helping military veterans transition to software careers. Rewrote our assessments and built an automated GitHub Actions pipeline for instant feedback and CI/CD grading, reducing assessment turnaround from days to seconds.

  • Senior Software Engineer at DUOS
    Nov 2021 - Oct 2022 · 1 yr