Senior Python Engineer Jobs in Ontario (NOW HIRING)

As a Python & SQL Developer, you will design, build, and support scalable backend and data‑driven solutions that enable modern applications and analytics platforms. In this 1‑year fixed‑term role, you will work closely with engineers, data teams, architects, and business stakeholders to deliver robust APIs, database‑driven services, and automation solutions. The role emphasizes strong Python development, SQL expertise, solution architecture, and people skills, with exposure to modern GenAI‑enabled capabilities where relevant.

• Design, develop, test, and debug backend services and APIs using Python and FastAPI, ensuring high performance, reliability, and maintainability
• Build server‑side logic, integrate RESTful services, and support microservice‑based architectures aligned with enterprise standards
• Work extensively with SQL‑based data sources, writing, optimizing, and maintaining complex queries, views, and stored procedures to support application logic, reporting, and data enrichment
• Develop scripts and services for data extraction, transformation, processing, and system automation, integrating both relational (SQL) and NoSQL (MongoDB) databases
• Contribute to solution and application architecture, including system design, integration patterns, data flows, and scalability considerations
• Collaborate with architects and senior engineers to ensure solutions are secure, well‑designed, and production‑ready
• Support GenAI‑enabled features where applicable, such as prompt design, retrieval from structured data, and vectorized search, without being focused on model development
• Partner closely with cross‑functional teams and stakeholders, applying strong people and communication skills to translate requirements, explain technical concepts, and support delivery from design through production

This is your opportunity to work in Operate at Deloitte. Operate services harness the latest technologies, talent, and capabilities from all over the world to deliver ongoing outcomes and client value. We do more than traditional business process outsourcing. We do more than just “keeping the lights on.” We work shoulder-to-shoulder with clients and their customers, constantly adapting to the pace of change, to ideate, innovate, and embed continuous advantage at the heart of their operations. And we do it with the kind of drive and passion that comes from loving what you do—and who you do it with.

You are someone with these skills, experience and qualifications: 

• Strong proficiency in Python (3.x) for backend and data‑driven application development
• Hands‑on experience with FastAPI for building scalable, production‑grade APIs
• Strong experience with SQL, including writing and optimizing complex queries, joins, CTEs, views, and stored procedures
• Backend development experience building server‑side logic, RESTful APIs, and microservices
• Experience working with relational databases and NoSQL databases (e.g., MongoDB)
• Experience developing scripts for data extraction, processing, and automation

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

• Exposure to GenAI‑enabled application features, including:
  • Prompt engineering
  • Retrieval patterns using structured data
• Experience with vectorization, embeddings, or RAG‑style data retrieval
• Familiarity with modern data platforms, analytics pipelines, or AI‑assisted features
• Understanding of performance tuning, scalability, and operational support in production environments

The salary range for this position is $72,000 - $138,000, 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.