Senior Software Engineer, Asynchronous Processing

Overview As a Senior Platform Engineer on the Asynchronous Processing team, you will architect, build, and operate Klaviyo’s high-scale, event-driven backbone. You will craft multi-tenant, self-service queueing platforms that scale to millions of messages per second with low latency. You’ll partner across teams to turn complex distributed-system problems into reliable building blocks and shape the core infrastructure that powers product teams. This role offers impact at scale and the chance to advance the platform with modern tech. Compensation / Benefitsbase salaryannual cash bonus planequitysign-on paymentshealth, welfare, and wellbeing benefitsrelocation support ResponsibilitiesArchitect and operate large-scale, event-driven backbone powering Klaviyo servicesDesign and evolve resilient, multi-tenant queueing and processing platformsBuild self-service APIs and tooling to enable product teams to move fastFocus on availability, latency, scalability, and observability across systemsCollaborate with engineers across the company on technical design reviewsMentor engineers, promote performance and self-healing practicesParticipate in on-call duties and drive incident RCAs to prevent recurrence Key requirements6+ years of hands-on software development experience at SaaS scaleBA or BS in Computer Science or related field, or equivalent experienceExperience owning full lifecycle of complex projects including design and rolloutOperational health ownership: performance, reliability, observabilityFamiliarity with AWS, Terraform, Kubernetes; ability to design services for scaleHands-on experience with asynchronous processing/queueing (SQS, Kafka, Pulsar)Strong communication, collaboration, and mentoring abilitiesComfort with on-call, incident management, and root-cause analysisexcellent communicationcollaborationproactive problem-solvingPythonGo (Golang)Apache Pulsar