Senior Software Engineer

Senior Software Engineer — Content ToolsContent ToolsCoCounsel Legal Integrations
Overview of the RoleThe CoCounsel Legal Integrations team within Thomson Reuters is seeking Senior Software Engineers to join the Content Tools team in building purpose-built APIs that give AI agents precise, governed access to TR’s proprietary legal content across various international jurisdictions. These tools are the bridge between TR’s authoritative content and the AI products, such as CoCounsel Legal, that depend on them, and they carry high stakes — every result must be accurate and grounded in TR’s authoritative content. This is a full-ownership engineering role on a team that designs, develops, tests, deploys, and operates the production content APIs that agentic workflows rely on.
The team’s operating principles are non-negotiable: you own what you build end-to-end, from the first commit to the production dashboard. You ship to production constantly, and you treat delivery friction as an engineering problem to solve, not a fact of life. You use AI-assisted development as a primary tool, with the expectation that the majority of code is written with AI assistance. And you practice verified spec-driven development: you write the acceptance criteria and utilize evaluation datasets that specify a tool’s behavior before you build it, and that eval suite gates every change in CI. Senior Engineers own a tool, subsystem, or content domain end-to-end, hold design‑decision authority within their scope, serve as the team’s subject‑matter expert in at least one area, and mentor more junior colleagues. This is a role for someone who takes genuine pride in the quality, reliability, and pace of their work.
About The RoleAs a Senior Software Engineer, you will:
Content Tool Engineering
Design, develop, and own Content Tools end-to-end: the APIs and retrieval components that let agents query TR legal content through precise, well‑documented, contract‑driven interfaces, for example, jurisdiction‑specific tools spanning legal content across multiple geographies
Build API‑first: every tool ships with a versioned contract, schema, and ownership metadata so consuming teams and agent developers can use it self‑service, without needing to ask you how it works
Design retrieval components for agentic use: respect explicit latency budgets across multi‑hop chains, shape result payloads with token economy in mind, and build clean tool boundaries that give agent orchestrators predictable interfaces
Build and tune the retrieval and search behind the content tools in collaboration with our research scientists from TR Labs — improving relevance and ranking quality on our Vespa based search platform.
Practice verified spec‑driven development: write the acceptance criteria and utilize evaluation datasets that define a tool’s behavior before you implement it — the eval is the spec — then build the eval suite, gold data, and CI gates that verify every change
Work in the team’s core stack — Python, FastAPI, and Pydantic on AWS, search in Vespa, with CI in GitHub Actions and observability in Datadog — building agent tools on the Claude Agent SDK and exposing them to agents over MCP (Model Context Protocol), and contributing to the shared libraries, generators, and patterns that help the whole team build tools correctly
Reliability & Operations
Participate in the on‑call rotation and take end‑to‑end ownership of incidents in your scope — triage, root‑cause analysis, clear communication, and post‑mortems that surface systemic fixes;
you built it, you run it. Write and improve the runbooks for your areas.
Treat delivery friction as a bug: a slow deploy, a flaky test, or a painful local workflow is a problem worth fixing, because the team’s ability to ship constantly depends on every engineer pushing back on friction
Instrument your components with structured logging, metrics, and distributed tracing;
for agentic retrieval paths, capture tool‑invocation sequences and per‑hop inputs so non‑deterministic failures can be diagnosed and reproduced
Define and monitor SLOs for the tools you own, and treat fast, safe delivery as part of the job rather than a trade‑off against reliability
Use AI‑assisted development tools fluently across your workflow — generation, review, testing, debugging, — and model effective patterns for the team
Technical Leadership & Collaboration
Take technical direction for your tools with design‑decision authority within your scope;
break product and customer requirements into work the team can execute, and provide technical input on feasibility rather than only receiving tasks
Serve as the team’s go‑to subject‑matter expert for at least one content domain or tool family;
provide domain‑expert review on high‑risk PRs and mentor more junior engineers through code review, pairing, and coaching
Work with our R&D division (TR Labs) and research scientists — alongside them, not receiving handoffs — to bring new retrieval capabilities into tools in a well‑tested, observable, responsible way
Build working relationships with CoCounsel Engineering and product owners
Capture decisions in writing through project‑level ADRs, and communicate clearly to both technical and non‑technical audiences
Champion ethical AI and secure, responsible engineering across your work
About YouYou’re a fit for the Senior Software Engineer role if you bring:
Required Experience
Bachelor’s or Master’s degree in Computer Science, Engineering, or a related field
5+ years of software engineering experience designing, developing, and testing production backend, API, or data‑infrastructure systems, with demonstrated end‑to‑end ownership of features and components
Mastery of Python and strong fundamentals, including API design and a rigorous testing discipline (unit, integration, and evaluation) — you write high‑quality production code and test everything you ship
Solid distributed‑systems knowledge: you understand the failure modes of services, queues, and datastores and design systems resilient to them
Proficiency with AWS cloud services, Datadog and CI/CD practices (Blue/Green, Canary deployments);
you ship small PRs frequently with fast feedback loops
Demonstrated operational ownership: on‑call participation, architectural documentation and decision records, post‑mortems, and a clear philosophy that building and operating are inseparable
Fluency with AI‑assisted development tools as a primary part of your workflow — you write the majority of your code with AI assistance and use it to accelerate delivery without sacrificing quality, and you own the outcome irrespective of how the code was produced
Proven ability to communicate technical concepts clearly to technical and non‑technical audiences, including design documents and component documentation
Preferred Experience
Working knowledge of information‑retrieval fundamentals (precision/recall trade‑offs, hybrid search, ranking) and how low‑level retrieval signals connect to downstream product quality
Experience building tools or APIs for agentic AI systems, including tool protocols such as MCP (Model Context Protocol) or similar
Background in legal technology, knowledge management, or other high‑stakes information domains where source attribution, accuracy, and entitlement matter
Familiarity with search and retrieval engines (Vespa, OpenSearch, Elasticsearch) at the level of writing queries, designing indexes, or operating clusters
Experience integrating AI services — embedding APIs, re‑ranking models, RAG‑supported retrieval — with error handling and fallback strategies in production
Familiarity with API gateways (such as Apigee) and how a content API is secured, versioned, and exposed to consumers
Experience with agent and retrieval evaluation: deterministic eval suites and gold data gated in CI, red‑teaming for prompt injection (e.G., Promptfoo), and tracing for LLM workflows (e.G., Langfuse)
Working understanding of infrastructure‑as‑code (Terraform) and container orchestration (ECS or Kubernetes), with the ability to configure and optimize CI/CD pipelines
This posting is for proactive recruitment purposes and may be used to fill current openings or future vacancies within our organization.
What’s in it For You?
Hybrid Work Model: We’ve adopted a flexible hybrid working environment 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 tomorrow’s 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 match. In 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. For any eligible US locations, unless otherwise noted, the base compensation range for this role is $102,200 USD - $189,800 USD. For Ontario, Canada, the base compensation range for this role is $111,400 CAD - $161,400 CAD. Base pay is positioned within the range based on several factors including an individual’s 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 UsThomson 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 26,000 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 View email address on ca.hrm.tc. 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 here.
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