Software Engineer II - RecommendationsPosted today$174K

The opportunity

At Klaviyo, we value the unique backgrounds, experiences and perspectives each Klaviyo (we call ourselves Klaviyos) brings to our workplace each and every day. We believe everyone deserves a fair shot at success and appreciate the experiences each person brings beyond the traditional job requirements.

What you'll do

  • Contribute to the architecture and evolution of backend services that power: product recommendations across Klaviyo experiences (email, SMS, KAgent, onsite, etc.), meeting standards for reliability, performance, and clear APIs.

  • Contribute to and maintain robust, large-scale data processing pipelines: (e.g., using Apache Spark or similar frameworks) that transform raw events and catalog data into high-quality features and inputs for recommendation models, ensuring data quality and lineage.

  • Collaborate closely with ML engineers and product stakeholders to: productionize recommendation models —defining high-level interfaces, feature contracts, and deployment patterns for batch and/or real-time inference systems.

  • Contribute to the development of the vector database that powers: recommendation, semantic search, and agentic use cases.

  • Ensure data and service observability (metrics, logging, tracing, dashboards): to facilitate recommendations that are correct, explainable, fast, and highly available for all customers.

  • Work with Product to break down projects into clear milestones, balancing the: need for rapid experimentation with technical soundness and long-term maintainability.

What they're looking for

  • Lead data-driven decision making and A/B testing efforts —ensuring: recommendation systems are instrumented with the right metrics, and independently interpreting results to guide future product and engineering iterations.
  • Participate in on-call and incident response for the systems you own, driving: major post-incident follow-ups that substantially improve the resilience and operability of our recommendation stack.
  • Integrate AI into your and the team’s development workflow from the ground up: —for example, using AI to accelerate development, automate complex tests, or build smarter monitoring and debugging tools.
  • Share knowledge, mentor junior engineers, and define best practices on: working with large-scale data frameworks, distributed systems, and integrating ML into production systems.