Senior Software Engineer AI

Thomson Reuters • Toronto, ON

2d • $118,400 - $219,800 • Hybrid

About The Position

The Senior Software Engineer, AI is a hands-on technical contributor in Thomson Reuters’ Global Westlaw Engineering organization. The role builds and operates full-stack products, AI-enabled features, and services for Westlaw, including agentic legal research experiences and retrieval services grounded in trusted legal content. The engineer designs and writes production code, contributes to architecture, and helps raise the team’s engineering standards.

The position uses agentic systems, retrieval-augmented generation (RAG), large language models (LLMs), and AI-assisted development to deliver secure, scalable, reliable, and high-performing solutions. It involves production ownership from development through deployment, monitoring, and reliability, while collaborating with Product, Design, and cross-functional teams and mentoring engineers.

The posting is for proactive recruitment and may be used to fill current openings or future vacancies. The role uses a flexible hybrid work model for office-based positions, with work from anywhere for up to eight weeks per year. The role may also be eligible for an annual bonus based on enterprise and individual performance.

Requirements

• At least 5 years of hands-on software engineering experience across front-end and back-end, building scalable web applications.
• A track record of shipping and operating production-grade full-stack systems at scale, including secure coding practices and reliability.
• Hands-on experience building with LLMs in production or serious prototypes, such as RAG, prompt and context design, evaluation, or agent workflows, and daily use of AI coding tools such as GitHub Copilot, Cursor, or Claude Code.
• Hands-on experience working in a team that builds and uses AI agents, with strong review, quality, and security practices.
• Clear understanding of RESTful API design, including resource modeling and URI design; correct use of HTTP methods and status codes; idempotency; pagination, filtering, and versioning; authentication and authorization; consistent error handling; and API documentation such as OpenAPI/Swagger.
• Strong proficiency in Python and experience designing and building RESTful APIs.
• Working proficiency in React or a similar modern UI framework such as Angular or Vue, and experience with TypeScript and Node.js.
• Strong knowledge of AWS architecture and services, with experience in DevOps, CI/CD pipelines, and infrastructure as code.
• Experience mentoring and supporting the growth of other engineers.
• Experience partnering with Product, Design, and cross-functional teams.
• Excellent communication skills, including providing clear updates, direct feedback, and stakeholder alignment.
• Comfort operating in a fast-moving, ambiguous environment and making data-driven decisions as priorities evolve.
• A strategic mindset and ability to align technical decisions with business goals.
• A bachelor’s degree in computer science, engineering, or a related discipline, or equivalent practical experience.

Nice To Haves

• Experience shipping AI-driven or agentic systems in production, such as LLM orchestration, RAG and information retrieval, agent frameworks, or tool protocols such as MCP, using LLM APIs from OpenAI or Anthropic reliably at scale.
• Experience with agent evaluation, including testing, benchmarking, and monitoring agent behavior.
• Experience with Python frameworks such as Django, Flask, or FastAPI.
• Experience across front-end, back-end, and AI engineering disciplines.
• A track record of helping teammates adopt new tools and ways of working.
• Exposure to legal or other regulated professional domains.
• AWS certifications, such as Solutions Architect or DevOps Engineer.

Responsibilities

• Design, build, and ship scalable user interfaces, backend services, and RESTful APIs.
• Build GenAI and LLM integrations, including agentic workflows, prompt and context design, and retrieval services grounded in trusted legal content.
• Contribute to architecture, engineering standards, coding practices, and code reviews, taking deep technical ownership.
• Own work through reliable production operations, including build, deployment, monitoring, and reliability, supported by automation and CI/CD.
• Ensure delivery meets functional and non-functional requirements, including performance, scalability, reliability, security, and maintainability.
• Embed quality and security throughout development with rigorous testing, secure coding practices, and continuous quality evaluation.
• Design and build cloud-native solutions on AWS.
• Evaluate and integrate emerging tool protocols, such as MCP, and retrieval patterns, considering production readiness and operational implications.
• Resolve critical production issues and drive root-cause fixes.
• Use AI-assisted and agent-driven development daily, monitoring and optimizing token consumption to balance productivity, quality, and cost.
• Deliver features using AI agents with clear task specifications, careful human review of generated code, and accountability for shipped work.
• Apply AI across the engineering lifecycle, including code generation, code review, test automation, and quality evaluation, with guardrails for security, data handling, and responsible use.
• Help measure AI and agent impact on delivery speed, code quality, and defect rates.
• Build and apply agent evaluation practices, including testing, benchmarking, and monitoring agent behavior.
• Mentor and coach engineers, sharing knowledge in information retrieval, agentic system design, and AI-assisted development.
• Model continuous learning and introduce new tools, practices, and ways of working.
• Partner with Product, Design, and cross-functional teams to translate requirements into well-designed solutions.
• Explain technical concepts and trade-offs clearly to stakeholders.
• Deliver solutions aligned with product roadmaps through incremental delivery, managing dependencies and tracking success metrics.
• Follow and help improve secure engineering processes for the team building and delivering legal research products.
• Stay current with developments in AI, cloud computing, and software engineering and bring them into team practices.

Benefits

• Flexible hybrid work environment for office-based roles.
• Work from anywhere for up to eight weeks per year.
• Flexible vacation and paid time off, including sick and safe time and paid holidays.
• Two company-wide Mental Health Days off annually.
• Access to the Headspace app and Employee Assistance Program.
• Retirement savings plan, including a 401(k) with company match for eligible U.S. employees.
• Tuition reimbursement.
• Employee incentive programs; the role may be eligible for an annual bonus.
• Health, dental, vision, disability, and life insurance programs.
• Parental leave and sabbatical leave.
• Flexible Spending and Health Savings Accounts.
• Fitness reimbursement.
• Commuter benefits.
• Adoption and surrogacy assistance.
• Employee Stock Purchase Plan.
• Two paid volunteer days off annually and opportunities for pro-bono consulting and ESG initiatives.
• Flexible workplace policies and career development and skills-development programs.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior