Senior Backend Developer, AI Systems

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Backend Developer, AI Systems based in Canada. As a Senior Backend Developer, you will play a leading role in evolving a large-scale AI-powered recommendation engine into a modern, scalable distributed architecture. You will design and operate high-performance backend systems that support billions of real-time marketing decisions for major global brands. Working at the intersection of distributed systems, machine learning, and software engineering, you will help build reliable infrastructure that directly impacts customer performance and revenue. You will take ownership of critical technical components, from architecture and implementation to deployment and production monitoring. Collaborating closely with machine learning engineers, product stakeholders, and fellow developers, you will influence technical strategy and engineering best practices. This is an opportunity to tackle complex systems challenges while contributing to an innovative, collaborative, and globally distributed technology environment. Accountabilities: - Lead the architectural transformation of the core recommendation pipeline into a modern distributed system, delivering incremental improvements while maintaining production stability and reliability. - Design, develop, deploy, and operate scalable, fault-tolerant backend services supporting large-scale personalization capabilities, including content selection, send-time optimization, subject line personalization, and frequency capping. - Identify, investigate, and resolve performance bottlenecks, reliability issues, and scalability limitations across distributed systems. - Collaborate with machine learning engineers and product stakeholders to translate business and technical requirements into robust architectural designs and production-ready solutions. - Take end-to-end ownership of critical system components, overseeing architecture, development, implementation, deployment, monitoring, and incident response. - Champion engineering best practices across system design, code quality, automated testing, observability, and operational excellence.

- Contribute to the continuous improvement of distributed infrastructure, ensuring high availability, fault tolerance, and efficient system performance. - Provide technical leadership and mentorship to other engineers, encouraging knowledge sharing, sound architectural decisions, and strong engineering standards. - Participate in architectural discussions and technical decision-making, helping shape the long-term direction of AI infrastructure and backend systems. - Promote a culture of accountability, technical excellence, collaboration, and continuous learning. Requirements: - At least 5 years of professional software engineering experience, with a strong focus on distributed systems. - Extensive experience designing, building, and operating large-scale distributed systems that are highly available, fault-tolerant, and capable of handling high concurrency. - Strong software engineering fundamentals, including system design, unit testing, Git, code reviews, and continuous integration and delivery practices. - Strong programming skills in Python and experience developing reliable, maintainable backend services. - Experience with distributed data processing frameworks such as Apache Spark, Apache Flink, or Apache Beam. Hands-on experience with Apache Spark is considered an advantage. - Solid understanding of distributed systems fundamentals, including consensus, partitioning, replication, back-pressure, idempotency, and failure handling. - Practical experience with cloud infrastructure providers such as Google Cloud Platform (GCP), AWS, or Microsoft Azure. - Familiarity with modern distributed systems and microservices technologies, particularly Kubernetes, Kafka, and gRPC.