At Justworks, you’ll enjoy a welcoming and casual workplace, great benefits, wellness program offerings, company retreats, and the ability to interact with and learn from leaders in the startup community. We work hard and care about our most prized asset - our people. We’re helping businesses get off the ground by enabling them to focus on running their business.

We’re data-driven and never stop iterating. If you’d like to work in a supportive, entrepreneurial environment, are interested in building something meaningful and having fun while doing it, we’d love to hear from you. These are best summed up in our company values, which are reflected in our product and in our team.

You care more about solutions and impacting the customer experience than using a particular tool or framework. You will join a small, highly autonomous cross-functional team to build AI agents that fundamentally transform how operations work at scale. Instead of writing bespoke software for every workflow, we are developing an agent platform that can read operational knowledge, reason about it in context, and execute tasks end-to-end.

We are seeking a Senior Software Engineer with a strong passion for building AI-native systems in a product environment. The ideal candidate will be able to take ownership of large segments of the technology stack, make pragmatic technical decisions in ambiguous and emerging territory, and consistently ship high-quality, production-ready systems that our users rely on every day. APIs, data access patterns, and service integrations for agents to execute operational workflows.

Architect the knowledge and memory infrastructure, allowing agents to retrieve the data and act across our systems. Design and implement the trust and safety framework, including audit trails, human-in-the-loop controls, and guardrails for safe and auditable AI-driven operations.



Contribute to agent evaluation and testing infrastructure, defining how we measure accuracy, reliability, and regression across agent behaviors.

You are comfortable in a fast-paced, early-stage environment. You are pragmatic and balance quality with speed. You understand when to optimize for long-term durability and when to iterate quickly. You prioritize pragmatism over being overly precious about code, but never compromise on quality in a way that creates future issues.

You look beyond the immediate task, seeking to understand the "why" behind the build and questioning whether it's the right product solution. You possess strong backend engineering fundamentals. You are curious and eager to develop expertise in AI and LLMs.

While deep research is not required, you are motivated to build practical, real-world products using these tools, specifically focusing on agent systems. 5+ years of backend engineering experience building and operating production systems ~ Hands-on experience with LLMs and AI agents (orchestration, RAG, tool/function calling, or similar) ~ Proven ownership of complex projects in ambiguous, early-stage environments The base wage range for this position based in our Toronto office is targeted at $188,000.00 to $242,000.00 CAD per year. #Diversity At Justworks Justworks is committed to maintaining a workplace where diversity of identity, culture, and life experience is the norm and is celebrated authentically and respected consistently. Diversity in our work, our people, and our product drives creativity and innovation,



entrepreneurial leadership and integrity, competitiveness, and collaboration throughout our business and in the market. We depend on our differences to make our team stronger, our workplace more dynamic, and our product accessible to all of our customers.

We’re proud to be an equal opportunity employer open to all qualified applicants regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital or familial status, disability, pregnancy, gender identity or expression, veteran status, genetic information, or any other legally protected status. Justworks is fully dedicated to providing necessary support to candidates with disabilities who may require reasonable accommodations. We also provide reasonable accommodations to employees based on their sincerely held religious beliefs, as well as for other covered reasons consistent with applicable federal, state, and local laws.

We’re committed to building a culture where everyone feels welcome, supported, and empowered to thrive. We believe that a wide range of perspectives, experiences, and identities strengthens our team and helps us create the kind of workplace—and world we want to see. Of course, thinking around these areas is ever-evolving so, wherever applicable please feel free to select "I prefer to self-describe" and then elaborate so we can use your feedback to inform survey selections in the future.

Participation in this survey is completely optional. At Justworks, we are building an open, inclusive, and collaborative culture that values each person’s unique potential. We strive to help every Justworker grow with confidence in the collective service of our company, our community, and our customers.

We’re proud of the company we’re building together, one great Justworker at a time. #

📌 Senior Software Engineer, Ai (Toronto)
🏢 Justworks
📍 Toronto