Senior Back-end Engineer

Adastra Corporation•Markham, ON

35d•Remote

About The Position

We are looking for a Senior Back‑end Engineer to design and build scalable, secure, and high‑performance backend systems that power modern SaaS applications. In this role, you will lead the architecture and development of .NET‑based microservices, define APIs that align with frontend workflows, and contribute to cloud‑native solutions on Azure. You will work closely with cross‑functional teams to deliver reliable backend services that support real-time user experiences, AI‑driven capabilities, and enterprise‑grade platforms.

Requirements

Strong experience designing and building backend systems using .NET and microservices architectures
Experience designing and consuming REST and event‑driven APIs
Hands‑on experience with Azure cloud services and cloud-native 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 AI‑related workloads
Ability to collaborate effectively with frontend engineers, architects, and product teams
Experience mentoring engineers or providing technical leadership

Nice To Haves

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

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 high‑availability REST and event-driven APIs to support real-time user interactions
Design and maintain Azure-based cloud infrastructure including App Services, API Management, Service Bus, and storage solutions
Develop Python-based services for AI model orchestration, data processing, and retrieval-augmented 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