Sr Backend Python Developer Jobs in Toronto, ON (NOW HIRING)

Overview

We are looking for a Senior Backend Engineer to design and build scalable, secure, and highperformance backend systems that power modern SaaS applications. In this role, you will lead the architecture and development of .NETbased microservices, define APIs that align with frontend workflows, and contribute to cloudnative solutions on Azure. You will work closely with crossfunctional teams to deliver reliable backend services that support realtime user experiences, AIdriven capabilities, and enterprisegrade platforms.

Primary Location: Across Canada or USA

Work Model: Fully Remote

Employment Type: Contractor

Vacancy Status: New

RESPONSIBILITIES

• Design and implement scalable backend architectures supporting frontend SaaS applications using .NET microservices
• Define and maintain API contracts aligned with frontend workflows and UI data requirements
• Lead the design of microservices for knowledge base management, agent configuration, integrations, and chat services
• Architect and implement secure authentication and authorization services using enterprise identity solutions
• Build highavailability REST and eventdriven APIs to support realtime user interactions
• Design and maintain Azurebased cloud infrastructure including App Services, API Management, Service Bus, and storage solutions
• Develop Pythonbased services for AI model orchestration, data processing, and retrievalaugmented generation pipelines
• Implement scalable services for conversation history and context management
• Establish CI/CD pipelines and DevOps practices for microservices deployment
• Ensure system observability through logging, monitoring, and distributed tracing
• Define backend performance optimization strategies and caching mechanisms
• Mentor backend engineers and promote architectural best practices

QUALIFICATIONS, SKILLS & EXPERIENCE

• Strong experience designing and building backend systems using .NET and microservices architectures
• Experience designing and consuming REST and eventdriven APIs
• Handson experience with Azure cloud services and cloudnative architectures
• Proficiency in backend API design, scalability, and performance optimization
• Experience with authentication and authorization in enterprise environments
• Working knowledge of CI/CD pipelines and DevOps practices
• Experience with Python for backend services, data processing, or AIrelated workloads
• Ability to collaborate effectively with frontend engineers, architects, and product teams
• Experience mentoring engineers or providing technical leadership

NICE TO HAVE

• Experience working with AI platforms, model orchestration, or RAG pipelines
• Familiarity with distributed systems observability tools and practices
• Experience designing realtime or conversational systems
• Exposure to largescale SaaS or enterprise platforms
• Experience with Retrieval-Augmented Generation (RAG) patterns for AI-driven applications

ABOUT ADASTRA

Adastra is a global leader in AI and data-driven transformation, helping organizations lead with artificial intelligence-responsibly, strategically, and at scale. With over 25 years of experience, Adastra empowers enterprise clients to unlock business value through data innovation, operational excellence, and smart customer engagement.

Trusted by some of the world's most prominent brands, Adastra delivers end-to-end solutions grounded in thoughtful strategy, robust governance, and deep technical expertise. From defining vision to ensuring execution, Adastra guides organizations through every stage of their AI, data and cloud journey-building future-ready capabilities and delivering measurable, lasting impact.

Adastra serves clients across key industries including financial services, automotive, manufacturing, technology, media and telecom (TMT), healthcare, retail, and professional services. The company employs more than 2,000 professionals across North America, Europe, and Asia.

WHAT WE OFFER

• Opportunity for advancement and career progression
• Competitive compensation
• Successful referral program
• The opportunity to work with one of Canada's 50 Best Managed Companies
• Satisfaction of working for a reputable company 
• A flexible, dynamic, and diverse workplace

EQUAL OPPORTUNITY EMPLOYER

In our commitment to promote fair and equitable treatment of all employees and applicants, Adastra Corporation provides equal employment opportunities for all individuals regardless of age, sex, disability, race, ethnic origin, citizenship, creed, sexual orientation, marital status, or any other ground as described in the Ontario Human Rights Code.  In addition, accommodation will be provided during the hiring process. Adastra Corporation's implementation and support of employment initiatives, encourage diversified labour force participation and equal access to opportunities based on merit and performance.

AI Usage - Our hiring process includes the use of AI-enabled tools to screen applications (e.g., keyword matching, qualification ranking). A human recruiter reviews all AI-generated shortlists to make informed hiring decisions.

There has been an increased instance of fraudulent job offers coming from people posing as Adastra HR employees. Please note that Adastra will never request fees as part of our recruiting process and any emails sent to you that are not from '@adastragrp.com' or '@talent.icims.com' are fraudulent. All employment offers are sent via DocuSign and if you receive an employment offer from a suspicious email and not via DocuSign, it is fraudulent.

Contact careers@adastragrp.com to inquire about jobs at Adastra, to report a suspicious request for money or personal information from external websites or suspicious employment offers.

Employment Type: OTHER