---
title: 'Member of Technical Staff, Research Engineer at Crosby'
canonical: 'https://feeny.ai/job/member-of-technical-staff-research-engineer-crosby-new-york-vdfv4p77xtnr'
type: 'job'
last_seen: '2026-09-10'
---

# Member of Technical Staff, Research Engineer at Crosby

- **Company:** Crosby
- **Location:** New York, NY
- **Compensation:** $200k–$300k
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2026-06-16
- **Last confirmed live:** 2026-09-10
- **Apply:** https://jobs.ashbyhq.com/crosby/81acae55-8c8e-40d9-b601-7ba99e22a6e2

## Job description

## About Crosby

Crosby is built on a simple conviction: a great legal system is the watermark of a great society — and the best legal work comes from combining human expertise with the right technology, not replacing one with the other.

Crosby is the first AI-native law firm, helping ambitious companies like Cursor, Ramp, and Cognition sign commercial contracts faster.

Legal work is both art and science, and we're mapping the frontier between the two — codifying what can be systematized, amplifying human judgment where it matters most. That's why the right way to bring AI into law isn't to sell software and walk away. It's to own the outcome together: higher-quality work, delivered faster. We build proprietary tools and human-in-the-loop workflows that change what's possible for corporate legal teams.

Crosby was founded by Ryan (Stanford Law, Cooley, startup GC) and John (Penn, first 15 engineers at Ramp). Help us transform one of society's most important industries.

## About the role

As a Research Engineer, you'll bridge research and production. You'll turn validated methods, benchmarks, and evaluation infrastructure from our research team into dependable, production-grade features. You’ll be responsible for the entire lifecycle of an AI feature—from building the underlying systems to customizing the models that make them run. Your work will involve both robust system design and the pragmatic application of advanced machine learning techniques, including model fine-tuning when necessary. This role is for a product-minded research engineer who knows how to get the most out of modern AI and is obsessed with shipping reliable, high impact features.

We also publish our work on legal AI at [intelligence.crosby.ai](http://intelligence.crosby.ai) — take a look at the kinds of problems you'd be working on.

## What you'll do

- Build core AI Systems: Design, build, and scale our primary AI features, including complex Retrieval Augmented Generation (RAG) pipelines and agentic workflows that make our models measurably better at contract review, playbook retrieval and docx editing.
- Build RL fine-tuning infrastructure: Stand up and harden RL training infrastructure (PPO, GRPO, and related methods) so researchers can train quickly and reliably at scale.
- Enable RL in a non-verifiable domain: Build reward pipelines, generators, and formal verification harnesses that make scalable RL possible in a domain like contract review.
- Customize Models for Impact: Selectively fine tune and adapt language models to improve their performance on highly specific legal tasks where off the shelf solutions fall short
- Ensure Production Quality: Develop evaluation and monitoring systems that catch regressions and reward hacking before they reach users.
- Apply AI Pragmatically: Stay on the frontier of AI research and identify the most effective techniques and tools to solve immediate product challenges.
- Collaborate to Ship: Work closely with product, backend, and our in house legal experts to deliver end to end solutions that make our users more effective.

## Who you are

- Experience: 3+ years of professional software engineering experience building and shipping AI/ML-powered products, with deep proficiency in Python and a proven track record of scalable, production-grade systems.
- Post-training expertise: Familiarity with post-training techniques such as SFT and GRPO, plus hands-on experience with the systems and frameworks that run them at scale—distributed model training, VERL, and vLLM.
- Practical AI skills: Hands-on experience with LLM APIs (e.g., OpenAI, Anthropic), RAG, agentic workflows, and the full ML project lifecycle.
- Analytical and pragmatic: A data-driven approach to problem solving and strong intuition for when to build complex infrastructure versus ship a simple solution.
- Product-focused: Driven by user impact and skilled at making smart technical trade-offs to deliver value quickly.
- Ownership: You thrive on taking full responsibility for features, from initial concept through deployment and iteration.

## Benefits & Perks

- Unlimited PTO
- Lunch & dinner in the office every day
- Medical insurance (multiple plan options through Anthem & Cigna)
- HSA or FSA, depending on your plan choice
- Dental insurance
- Vision insurance
- One Medical membership
- 401(k) match
- In-office desk setup stipend

## Equal Opportunity

Crosby is an equal opportunity employer. We do not discriminate based upon race, religion, color, national origin, sex (including pregnancy, childbirth, reproductive health decisions, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, genetic information, political views or activity, or other applicable legally protected characteristics.

Background checks for applicants will be administered in accordance with applicable law, and qualified applicants with arrest or conviction records will be considered for employment consistent with those laws, including the New York City Fair Chance Act.

Pursuant to New York Labor Law Section 194-b, the US Pay Range for this position is listed in the job post. Final compensation will be determined based on skills, experience, and qualifications.

## About Crosby

## Company Overview
- **One-liner**: Crosby is a hybrid AI-powered law firm that combines internally developed AI software with lawyer oversight to review and negotiate contracts in under an hour.
- **Entity Type**: Private (Series B)
- **Headquarters**: New York City, New York, United States
- **Founded**: 2024
- **Founders**: Ryan Daniels (CEO) and John Sarihan (CTO)

## Core Business
- Primary industry: Legal Services / Legal Tech
- Target customers: Fast-growing startups and B2B companies who need to accelerate contract review for MSAs, DPAs, and NDAs (B2B, Enterprise).
- Mission or purpose statement: To build the API for human agreement — combining the speed of AI with the safety of lawyers-in-the-loop to eliminate contract bottlenecks and enable faster business execution.

## Products & Services
- **[Contract Review Service]**: A full-service legal offering where Crosby handles contract review from start to finish. Clients send documents via Slack, email, or a CLM trigger. Crosby’s AI agents review the contract, and licensed lawyers ensure accuracy and quality. The service is priced at fixed rates per document, not by the hour. The median review time is 58 minutes.

## Market Standing
- **Valuation/Market Cap**: Not disclosed.
- **Total Funding**: $85.8M.
    - **Series B** ($60M, March 2026): led by Index Ventures and Lux Capital.
    - **Series A** ($20M, November 2025): led by Elad Gil and Index Ventures.
    - **Seed Round** ($5.8M, June 2025): led by Sequoia Capital and Bain Capital Ventures.
- **Notable Investors/Partners**: Sequoia Capital, Bain Capital Ventures, Index Ventures, Lux Capital, Elad Gil. Angel investors include the founders of Ramp (Eric Glyman, Karim Atiyeh), Instacart (Max Mullen), Opendoor (Eric Wu), Flatiron Health (Zach Weinberg, Gil Shklarski), and Casetext (Jake Heller).
- **Growth Signals**: The company has reviewed over 1,000 contracts since its soft launch in January 2025. It has grown from 19 employees at launch to 55 employees (as of mid-2026), with a monthly headcount growth rate of +7.1%. The company has secured major early customers including Cursor, Clay, and UnifyGTM. It has 24 active job postings and a quarterly job posting growth rate of +100%.

## Competitive Advantages
- **Hybrid Model**: Crosby is a licensed law firm, not just a software tool. Owning the end-to-end process allows it to guarantee quality with malpractice insurance, which pure AI tools cannot.
- **Speed of Execution**: The 58-minute median review time is a stark differentiator in an industry where contract negotiation can take weeks or months.
- **Talent Density**: The team combines top-tier legal talent (from Harvard, Stanford, Columbia Law, and firms like Cooley and Ropes & Gray) with elite engineering talent (from Ramp, Vanta, Meta, Google, Scale AI, and Palantir).
- **Pricing Model**: Fixed rates per document eliminate the billable hour, incentivizing speed and efficiency.

## Strategic Focus
- **Scaling the Team and Capabilities**: The new Series B funding is aimed at rapidly scaling the engineering, legal, and operations teams to serve a growing client base.
- **Further Reducing Review Time**: The company is actively working to bring review times down from under an hour to just minutes.
- **Deepening AI Integration**: Continuing to build and refine custom legal AI agents to automate more of the contract review process, while maintaining human oversight for quality.

## Why Work Here
- **Culture**: Crosby values people who "push limits and own the outcome." The team is described as stubborn, empathetic, and collaborative, with a strong emphasis on honesty and ownership. Learning and improvement are core to the DNA.
- **Work Environment**: In-person in New York City. The company provides lunch and dinner daily in the office, and offers relocation support to move to NYC.
- **Compensation & Benefits**: Competitive salary and equity, unlimited PTO, and comprehensive medical, dental, and vision insurance, plus a 401(k) with an employer match.
- **Role**: The company is building the "legal infrastructure of tomorrow," offering the chance to work at the frontier of AI and law on tangible, important problems. Titles range from "Member of Technical Staff" (Generalist, AI Researcher, Security Engineer, etc.) to "Founding Account Executive" and "Commercial Counsel."

## Sources
1. [crosby.ai](https://crosby.ai/)
2. [crosby.ai/careers](https://crosby.ai/careers)
3. [techcrunch.com](https://techcrunch.com/2025/06/17/sequoia-backed-crosby-launches-a-new-kind-of-ai-powered-law-firm/)
4. [linkedin.com](https://www.linkedin.com/company/crosbylegal)
5. [crosby.ai/blog](https://crosby.ai/blog/introducing-crosby-the-worlds-first-hybrid-law-firm)

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