Accounting Python Jobs in Ontario (NOW HIRING)

Lead Product Engineer (Full Stack), Materia AI

This role is heavily backend focused (roughly 70% backend / 30% frontend).

We are specifically looking for engineers who havebuilt and shipped real products end-to-end, not just contributed small features within large organizations.

Strong preference for candidates with:

• Hands-on ownership building production products from 01

• Python backend depth (FastAPI/Django/APIs/microservices)

• Scalable distributed systems

• Product engineering mindset

• Customer-facing feature ownership

• React/TypeScript capability to support full-stack delivery

• Startup or greenfield experience

• Engineers who can independently design, build, and deliver systems in production

Frontend experience is required, but this isNOT a frontend-heavy/UI-focused role. We need backend-first engineers who can also contribute across the stack when needed.

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Are you excited about building AI-driven software that redefines how professionals work?Have you built scalable Python backend systems that power customer-facing products?Join a dynamic and highly skilled team at Thomson Reuters, where we combine the agility and innovation of a startup with the stability and resources of a global leader. As a Lead Product Engineer, you will play a pivotal role indesigning and building the backend services and APIs that power AI-driven accounting workflows, while contributing across the full stack to rapidly iterate on features, drive user engagement, and optimize outcomes through data-driven experimentation.

Innovate in a Startup-Like EnvironmentBe part of a fast-moving, forward-thinking group that is creating AI-driven software for accounting professionals. You'll join a team of top engineers and AI developers, leveraging cutting-edge technology to build intelligent and scalable systems. This role is for the CoCounsel for Accounting team, formed from the recent acquisition of the startup Materia.

Create Impactful, AI-Driven ExperiencesLead backend-driven full stack initiatives - from Python-based AI services and APIs to the React interfaces that bring them to life. You'll architect and implement complete features that deliver generative AI capabilities, alongside core product systems that streamline and modernize accounting workflows. Building the intelligent backend systems and connecting them to polished user experiences, your work will shape how thousands of accounting professionals leverage AI and modern software in their everyday workflows.

Collaborate Across FunctionsWork closely with product managers, designers, and AI specialists to deliver elegant, high-performance features. Your ability to translate complex requirements into robust solutions - scalable APIs and services complemented by polished interfaces - will be key to our product's success.

About the Role:

In this role as aLead Product Engineer, you will work on abackend-leaning full stack teambuilding customer-facing product features.

This role is abackend-leaning full stack position. The team is looking for engineers with strongPython backend experiencewho have worked oncustomer-facing product systems. While the role involves both backend and frontend development, the primary focus is buildingscalable backend services and APIsthat power product features.

Candidates should have strong experience building backend systems usingPython frameworks such as FastAPI, Flask, or Django, and be comfortable designing APIs and services that operate at scale.

On the frontend side, the team works with modern frameworks includingReact, Next.js, and TypeScript, so candidates should be comfortable contributing across the stack and connecting frontend interfaces to backend services.

The ideal candidate has aproduct mindset, enjoysshipping features end-to-end, and works closely withproduct managers, designers, and engineering teamsto deliver high-quality user experiences. While the role is full stack,deep backend expertise in Python is the priority, with the ability to contribute to frontend development when needed.

Develop

• Design, build, and maintain the backend services powering generative AI products such as Conversations, Accounting Research, Ready to Advise, and Workspaces

• Develop robust backend systems with Python, FastAPI, Pydantic, and cloud infrastructure, including API design, data modeling, system architecture, and AI service integration

• Own complex, 6+ month projects from beginning to end, including ideation, working with cross-functional partners in product and UX, testing, launching, measuring impact, and iteration

• Contribute to front-end development using Next.js, TypeScript, and Tailwind CSS to connect interfaces to backend services

• Identify bottlenecks and optimize for speed, scalability, and responsiveness across the full stack

Collaborate & Lead

• Serve as a technical leader for backend-driven projects through making prioritization decisions, scoping out timelines, guiding the work of engineers, and collaborating with cross-functional partners

• Contribute to technical design decisions across the stack, including architecture, API design, and system integration patterns

• Set and enforce team-wide frameworks, best practices, and code quality standards for both backend and frontend development

• Mentor and develop junior and mid-level engineers through code reviews, technical guidance, and career development

• Establish and maintain high engineering standards for code quality, testing, and architecture

• Lead by example in technical excellence, delivery accountability, and collaborative problem-solving

Champion Product Quality

• Drive high standards for backend reliability, API design, and system performance

• Apply strong product sensibilities to deliver polished, accessible, and user-centric experiences

• Proactively collect feedback from end users and internal stakeholders, and iterate accordingly

About You:

You are a fit for a Lead Product Engineer (Full Stack) if your background includes:

We're looking for engineers withstrong Python backend experience and solid full-stack capability.You should be a backend-strong engineer who is comfortable working across the stack - someone who can architect robust services and APIs and also contribute effectively to the front end when needed.

Experience & Skills

• 7+ years building web applications at scale, with deep experience in backend development and practical front-end skills (we're looking for backend-strong engineers who can work across the full stack)

• Strong proficiency in Python and backend frameworks (FastAPI, Flask, or Django), with experience designing APIs and services that operate at scale

• Comfortable contributing to front-end development with React, Next.js, and TypeScript

• Appreciation for good UI/UX and product design - you care about the end-user experience even when your primary focus is backend systems

• Self-driven with a proactive approach to problem-solving and prioritization

• Experience building new products or features from 0 to 1 or from ideation to release

• Excellent debugging skills and an eye for performance optimization

• Strong leadership and cross-functional collaboration abilities

Bonus Points

Bachelor's degree in Computer Science or related field

Experience working in a startup or similar fast-paced setting

Experience building AI-native products, chatbot interfaces, or API-driven platforms

Familiarity with large language models (LLMs), AI agent design, and/or prompt engineering

Experience with cloud infrastructure, event-driven architectures, or observability tooling

Opinionated about testing methodologies, A/B testing, and safe rollouts

#LI-SM2

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 (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 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. 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 $136,000 USD - $253,000 USD. For any eligible US locations, unless otherwise noted, the base compensation range for this role is $118,400 USD - $219,800 USD. For Ontario, Canada, the base compensation range for this role is $140,600 CAD - $190,600 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 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 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 busin...