Principal Engineer, CoCounsel

Thomson Reuters

Job Location:

Eagan, MN - USA

Monthly Salary: Not Disclosed

Posted on: 3 days ago

Vacancies: 1 Vacancy

Job Summary

Principal Software Engineer CoCounsel

CoCounselis our most advanced AI offering to date combining generative and agentic AI capabilities to help legal professionals move beyond prompting and start delegating. As a Principal Software Engineer you will set the technical direction for the backend AI orchestration and identity systems that turn frontier models into reliable secure production-grade workflows that attorneys in-house legal departments and government agencies trust on real client matters every day.

This role sits at the heart of theCoCounselLegal engineering organization partnering closely with AI/ML engineers researchers product and our identity and platform teams to deliver world-class legal content and AI experiences at scale.

About the role:

In this opportunity as a Principal Software Engineer you will:

Participate in shapingthe companys AI platform and patterns:Define patterns for building MCP servers designing agents novel uses of LLMs experimentation and scalable infrastructure. Your decisions will influence multiple product lines not just a single feature.

Work at real production scale: Build and evolve systems that operate over millions of documents complex and ever-changing law privileged client data and thousands of concurrent AI interactions from professionals doing time-sensitive work. Considering implications tocloud costs optimizations etc.

Small team big surface area:Join a tight group of senior engineers and researchers shipping quickly with direct access to product leadership and customers. Think ownership of a startup with the runway of a public company.

Technical leadership and cross-functional influence:Leadand/or designinitiatives that cut across AI product identity and infrastructure.Mentor staff and senior engineers raising the bar onAI integration practicessystem design code qualityandsecurity across the org.Be the expert in new model capabilities collaborating closely with AI/ML engineers researchers designers and PMs to translate industry improvements into reliable user-facing workflows that legal professionals trust.Help shape the teams roadmap technical strategy and engineering culture from experimentation practices to testing rollout and postmortems.Help define and lead the platform integration strategy across new and existing Thomson Reuters legal systems to deliver world-class content and solutions for our customers.

Identity access and trust:Define how autonomous agents act on a users behalf safely: scoped delegation least-privilege service identities secrets management and consistent enforcement of entitlements across documents matters and content repositories.Partner with security platform and compliance teams on multi-tenancy isolation data residency privilege protection and the audit trails that legal and government customers require.Consider the design and evolution of authentication and authorization acrossCoCounselLegal SSO/federation (SAML OIDC OAuth 2.0) token and session management and fine-grained role- and attribute-based access control (RBAC/ABAC).

Scale reliability and performance:Design for high-throughput low-latency AI workloads: caching queuing rate-limiting model failover and cost/performance trade-offs.Work with large-scale data: millions of documents retrieval and search vector stores and indexing strategies tailored to legal use cases.Establish and refine SLOs observability and incident response for AI systems that must be correct auditable and trustworthy in professional legal workflows.

About You:

You are a fit for the position of Principal Software Engineer if your background includes:

Bachelors Degree in Computer Science Computer Engineering a related field or equivalent experience.

Demonstrated experience building with AI LLMs agents and retrieval and a strong point of view on what AI-native software should look like.

Proven track record owning large complex projects end-to-end: architecture execution rollout and long-term operation.

Deep Python expertise and experience with production systems using frameworks likeFastAPI(or similar) relational databases (PostgreSQL or equivalent) and a major cloud provider (AWS preferred).

Strong background in distributed systems: data modeling API contracts observability resilience patterns and performance tuning under load.

Hands-on experience with identity and access management designing or integrating authentication and authorization at scale (SSO SAML OIDC OAuth 2.0 RBAC/ABAC token/session management or comparable IAM systems).

Excellent communication skills and the ability to partner with product design security and ML teams in a fast-moving environment.

Preferred Skills & Experience:

Hands-on experience designing and operating agentic systems in production tool calling MCP servers multi-step workflows and orchestration around third-party and in-house LLMs (e.g. Anthropic OpenAI) including prompt/response management cost controls and safety considerations.

Experience with AI-adjacent infrastructure: vector databases embeddings semantic search or custom retrieval pipelines.

Opinions and experience around automated testing reliability and release practices for systems with non-deterministic model behavior.

#LI-ES1

Replacement: This position is open due to an existing vacancy to support our evolving business needs.

Whats in it For You

Hybrid Work Model: Weve adopted a flexible hybrid working environment (2-3 days a week in the office depending on the role) for our office-based roles while delivering a seamless experience that is digitally and physically connected.
Flexibility & Work-Life Balance: Flex My Way is a set of supportive workplace policies designed to help manage personal and professional responsibilities whether caring for family giving back to the community or finding time to refresh and reset. This builds upon our flexible work arrangements including work from anywhere for up to 8 weeks per year empowering employees to achieve a better work-life balance.
Career Development and Growth: By fostering a culture of continuous learning and skill development we prepare our talent to tackle tomorrows challenges and deliver real-world solutions. Our Grow My Way programming and skills-first approach ensures you have the tools and knowledge to grow lead and thrive in an AI-enabled future.
Industry Competitive Benefits: We offer comprehensive benefit plans to include flexible vacation two company-wide Mental Health Days off access to the Headspace app retirement savings tuition reimbursement employee incentive programs and resources for mental physical and financial wellbeing.
Culture: Globally recognized award-winning reputation for inclusion and belonging flexibility work-life balance and more. We live by our values: Obsess over our Customers Compete to Win Challenge (Y)our Thinking Act Fast / Learn Fast and Stronger Together.
Social Impact: Make an impact in your community with our Social Impact Institute. We offer employees two paid volunteer days off annually and opportunities to get involved with pro-bono consulting projects and Environmental Social and Governance (ESG) initiatives.
Making a Real-World Impact:We are one of the few companies globally that helps its customers pursue justice truth and transparency. Together with the professionals and institutions we serve we help uphold the rule of law turn the wheels of commerce catch bad actors report the facts and provide trusted unbiased information to people all over the world.

Our use of AI within the recruitment process Thomson Reuters utilizes Artificial Intelligence (AI) to support parts of our global recruitment process. Unless you opt-out our AI system will assess the information provided by you and compare it to the requirements listed for the role and present the result to our recruitment personnel for further review. The AI system acts as a supporting tool but there is always a human making the decision if you will be considered for the role.

In the United States Thomson Reuters offers a comprehensive benefits package to our employees. Our benefit package includes market competitive health dental vision disability and life insurance programs as well as a competitive 401k plan with company addition Thomson Reuters offers market leading work life benefits with competitive vacation sick and safe paid time off paid holidays (including two company mental health days off) parental leave sabbatical leave. These benefits meet or exceeds the requirements of paid time off in accordance with any applicable state or municipal laws. Finally Thomson Reuters offers the following additional benefits: optional hospital accident and sickness insurance paid 100% by the employee; optional life and AD&D insurance paid 100% by the employee; Flexible Spending and Health Savings Accounts; fitness reimbursement; access to Employee Assistance Program; Group Legal Identity Theft Protection benefit paid 100% by employee; access to 529 Plan; commuter benefits; Adoption & Surrogacy Assistance; Tuition Reimbursement; and access to Employee Stock Purchase Plan.

Thomson Reuters complies with local laws that require upfront disclosure of the expected pay range for a position. The base compensation range varies across locations. Eligible office location(s) for this role include one or more of the following: New York City San Francisco Los Angeles and/or Irvine CA; McLean VA; Washington DC. The base compensation range for the role in any of those locations is $183100 USD - $340000 USD. For any eligible US locations unless otherwise noted the base compensation range for this role is $158900 USD - $295100 USD. Base pay is positioned within the range based on several factors including an individuals knowledge skills and experience with consideration given to internal equity. Base pay is one part of a comprehensive Total Reward program which also includes flexible and supportive benefits and other wellbeing programs. This role may also be eligible for an Annual Bonus based on a combination of enterprise and individual performance.

About Us

Thomson Reuters informs the way forward by bringing together the trusted content and technology that people and organizations need to make the right decisions. We serve professionals across legal tax accounting compliance government and media. Our products combine highly specialized software and insights to empower professionals with the data intelligence and solutions needed to make informed decisions and to help institutions in their pursuit of justice truth and transparency. Reuters part of Thomson Reuters is a world leading provider of trusted journalism and news.

We are powered by the talents of 26000 employees across more than 70 countries where everyone has a chance to contribute and grow professionally in flexible work environments. At a time when objectivity accuracy fairness and transparency are under attack we consider it our duty to pursue them. Sound exciting Join us and help shape the industries that move society forward.

As a global business we rely on the unique backgrounds perspectives and experiences of all employees to deliver on our business goals. To ensure we can do that we seek talented qualified employees in all our operations around the world regardless of race color sex/gender including pregnancy gender identity and expression national origin religion sexual orientation disability age marital status citizen status veteran status or any other protected classification under applicable law. Thomson Reuters is proud to be an Equal Employment Opportunity Employer providing a drug-free workplace.

Thomson Reuters makes reasonable accommodations for applicants with disabilities including veterans with disabilities and for sincerely held religious beliefs in accordance with applicable law. If you reside in the United States and require an accommodation in the recruiting process you may contact our Human Resources Department at. Disability accommodations in the recruiting process may include things like a sign language interpreter making interview rooms accessible providing assistive technology or other relevant accommodations. Please note this email is not intended for general recruitment questions and we will promptly respond to inquiries regarding accommodations. More information on requesting an accommodation here.

Learn more on how to protect yourself from fraudulent job postings here.

More information about Thomson Reuters can be found on

Required Experience:

Staff IC

Principal Software Engineer CoCounselCoCounselis our most advanced AI offering to date combining generative and agentic AI capabilities to help legal professionals move beyond prompting and start delegating. As a Principal Software Engineer you will set the technical direction for the backend AI or...