Join to apply for the Founding Engineer (Full Stack) role at Crimson (YC X25)

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Join to apply for the Founding Engineer (Full Stack) role at Crimson (YC X25)

This range is provided by Crimson (YC X25). Your actual pay will be based on your skills and experience — talk with your recruiter to learn more.

Base pay range

Crimson is the AI platform for high-stakes litigation. We're working with top law firms in the UK and US to streamline how complex disputes are run. Our platform drafts pleadings and submissions, analyzes judgments and orders, summarizes transcripts and locates key evidence in seconds.

We're a team of three co-founders with deep technical and domain expertise. Our users are lawyers who trust us with their most sensitive case files. They care about security, accuracy, reliability and speed, and so do we.

We're looking for an exceptional full-stack engineer to join us as one of our first employees. You'll ship production code from day one and own major features end-to-end. That means talking to users, scoping the problem, building the solution and improving it over time.

What You'll Do

• Contribute to the entire stack, from cloud infrastructure to prompting to UX (Python backend, Next.js with TypeScript frontend, PostgreSQL, SOTA LLMs. Deployed to Azure via IaC (Bicep) with CI/CD pipelines powered by GitHub Actions)
• Collaborate closely with users to understand how lawyers work and what they need
• Architect and scale document ingestion and processing pipelines to power fast, accurate search and data extraction for large volumes of legal documents
• Develop intelligent, multi-step agent workflows that can autonomously handle complex legal tasks - from surfacing key testimony across depositions to generating fact chronologies and auto-detecting inconsistencies in opposing counsel’s filings
• Design and bring to life intuitive AI-native user experiences tailored to litigation workflows
• Improve system performance, stability and observability as we scale
• Help shape our engineering culture and team - from best practices to hiring and mentorship
  
  

• You’re driven, self-directed and exceptionally capable
• You’re obsessed with building outstanding products for demanding users
• You’re excited to work on hard problems, take ownership and push things through
• You have high agency and a bias for shipping
• You have excellent product judgement, communication skills and attention to detail
• Bonus points if you have an interest in legal tech
  
  

• Over the next few years, the legal industry will change beyond recognition. You’ll be at the heart of that change, helping us build a category-defining company
• We’re backed by YC and other top investors
• We’re working with major UK and US law firms
• You’ll get ownership, equity and the opportunity to shape the business and lead engineering teams
  
  

• Location: London/hybrid
• Salary: £70-100k
• Meaningful equity
• Contact: tell us about things you’ve built by emailing founders [at] crimson [dot] law. We’ll get back to you within 24h.

Seniority level

• Seniority level

  Mid-Senior level

Employment type

• Employment type

  Full-time

Job function

• Job function

  Engineering and Information Technology

• Industries

  Software Development

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