Lead Full Stack Developer - Delo

Job Type: Permanent
Work Model: Hybrid
Reference code: 133605
Primary Location: Toronto, ON
All Available Locations: Toronto, ON; Montreal, QC

Our Purpose

At Deloitte, our Purpose is to make an impact that matters. We exist to inspire and help our people, organizations, communities, and countries to thrive by building a better future. Our work underpins a prosperous society where people can find meaning and opportunity. It builds consumer and business confidence, empowers organizations to find imaginative ways of deploying capital, enables fair, trusted, and functioning social and economic institutions, and allows our friends, families, and communities to enjoy the quality of life that comes with a sustainable future. And as the largest 100% Canadian-owned and operated professional services firm in our country, we are proud to work alongside our clients to make a positive impact for all Canadians.

By living our Purpose, we will make an impact that matters.

• Have many careers in one Firm.
• Enjoy flexible, proactive, and practical benefits that foster a culture of well-being and connectedness.
• Learn from deep subject matter experts through mentoring and on the job coaching

What will your typical day look like?

• Design and build full-stack features across our React/Next.js front-end and Python/FastAPI back-end that power agentic, AI-native workflows.
• Architect agentic systems: multi-agent orchestration, tool-calling, RAG, structured outputs, guardrails, evals and human-in-the-loop checkpoints.
• Drive innovation by experimenting with new models, techniques, and technologies, and stay current with advancements in AI.
• Design and maintain APIs, data models, and integrations across SQL and NoSQL data stores.
• Collaborate cross-functionally with designers, product managers, and other engineers to deliver complete software solutions.
• Optimize application performance through caching, load balancing, and scalable architecture design.
• Write unit and integration tests to ensure code quality and reliability; participate in debugging and troubleshooting.
• Manage continuous integration and deployment pipelines (CI/CD) for automated testing and smooth releases.
• Document APIs, system architecture, and codebase for future maintenance and scalability.

About the team

Delo is building the next generation of enterprise AI: digital teammates that automate the work humans shouldn’t do, starting with Finance and expanding across the back office. Born inside Deloitte and now backed by the firm, Delo is creating Deloitte 2.0: a fully digital, AI-native version of the firm. Our platform orchestrates agentic AI, structured SOPs, and automated workflows across ERPs, CRMs, tax engines, and financial systems. Think: a reusable, multi-agent operating system for enterprise work. We’re early, truly 0→1, and building a scalable engineering foundation that will power dozens of agents, thousands of teams, and millions of automated tasks. If you want to build foundational infrastructure that will power AI-driven work for thousands of organizations, this is the moment to join.

Enough about us, let’s talk about you

You are someone who has these skills, experience & qualifications:

• 10+ years of software engineering experience, with strong front-end work in React/Next.js and back-end experience in Python/FastAPI or another modern web framework.
• Track record of designing and operating production systems at scale and setting the technical bar for others.
• Experience with event-driven architectures for orchestrating long-running agent runs and decoupling services.
• Strong with relational data modeling (PostgreSQL) and NoSQL (MongoDB, Elasticsearch).
• Experienced designing APIs and integrating front-end and back-end components cleanly and securely; solid on secure coding, auth, reusability and performance.
• Shipped LLM-powered features in production and understand the realities of non-determinism: prompting, evals, retries, fallbacks, and guardrails.
• Fluent with AI coding assistants (Cursor, Claude Code, Codex) as a daily driver.
• A clear communicator and detail-oriented engineer committed to clean, maintainable, testable code.

It would be great for you to have some of these nice to haves aswell:

• Experience building agentic systems and hands-on RAG with vector DBs (pgvector, elasticsearch, milvus).
• Built an LLM eval pipeline and familiarity with tool use, function calling, MCP, and structured outputs.
• Cloud platforms (AWS, Azure, GCP), containers (Docker, Kubernetes), and DevOps/Infrastructure as Code principles.
• Exposure to data governance, AI ethics, and compliance frameworks (SOC 2, GDPR, HIPAA)
• Prior startup or SaaS experience, especially in fintech, accounting, or ERP/CRM domains.

Total Rewards

The salary range for this position is $84,000 - $175,000, and individuals may be eligible to participate in our bonus program. Deloitte is fair and competitive when it comes to the salaries of our people. We regularly benchmark across a variety of positions, industries, sectors, targets, and levels. Our approach is grounded on recognizing people's unique strengths and contributions and rewarding the value that they deliver.

Our Total Rewards Package extends well beyond traditional compensation and benefit programs and is designed to recognize employee contributions, encourage personal wellness, and support firm growth. Along with a competitive base salary and variable pay opportunities, we offer a wide array of initiatives that differentiate us as a people-first organization. On top of our regular paid vacation days, some examples include: $4,000 per year for mental health support benefits, a $1,300 flexible benefit spending account, firm-wide closures known as "Deloitte Days", dedicated days of for learning (known as Development and Innovation Days), flexible work arrangements and a hybrid work structure.

Our promise to our people: Deloitte is where potential comes to life.

Be yourself, and more.

We are a group of talented people who want to learn, gain experience, and develop skills. Wherever you are in your career, we want you to advance.

You shape how we make impact.

Diverse perspectives and life experiences make us better. Whoever you are and wherever you’re from, we want you to feel like you belong here. We provide flexible working options to support you and how you can contribute.

Be the leader you want to be

Some guide teams, some change culture, some build essential expertise. We offer opportunities and experiences that support your continuing growth as a leader.

Have as many careers as you want.

We are uniquely able to offer you new challenges and roles – and prepare you for them. We bring together people with unique experiences and talents, and we are the place to develop a lasting network of friends, peers, and mentors.

The next step is yours

At Deloitte, we are all about doing business inclusively – that starts with having diverse colleagues of all abilities. Deloitte encourages applications from all qualified candidates who represent the full diversity of communities across Canada. This includes, but is not limited to, people with disabilities, candidates from Indigenous communities, and candidates from the Black community in support of living our values, creating a culture of Diversity Equity and Inclusion and our commitment to our AccessAbility Action Plan, Reconciliation Action Plan and the BlackNorth Initiative.

We encourage you to connect with us at accessiblecareers@deloitte.ca if you require an accommodation for the recruitment process (including alternate formats of materials, accessible meeting rooms or other accommodations) or indigenouscareers@deloitte.ca for any questions relating to careers for Indigenous peoples at Deloitte (First Nations, Inuit, Métis).

When you apply, we will review your application using Deloitte's Global Talent Standards to ensure a consistent recruitment experience. Our recruitment advisors and hiring teams will utilize human screening combined with AI technology to help identify the skills and qualities that matter most to our business, while safeguarding your privacy and using AI responsibly.

Deloitte Canada has 20 offices with representation across most of the country. We acknowledge that Deloitte offices stand on traditional, treaty, and unceded territories in what is now known as Canada. We recognize that Indigenous Peoples have been the caretakers of this land since time immemorial, nurturing its resources and preserving its natural beauty. We acknowledge this land is still home to many First Nations, Inuit, and Métis Peoples, who continue to maintain their deep connection to the land and its sacred teachings. We humbly acknowledge that we are all Treaty people, and we commit to fostering a relationship of respect, collaboration, and stewardship with Indigenous communities in our shared goal of reconciliation and environmental sustainability.