Senior Software Engineer, Platform Engineering

Requirements

• BA or BS Degree in Computer Science, related field, or equivalent experience.
• 5+ years of responsibility operating and scaling complex distributed systems.
• Experience working in a cloud-native environment.
• Proven experience developing applications in Python and Go.
• Fundamental understanding of Linux and all layers of the networking stack.
• Experience in a subset of platform-related areas such as Kubernetes, infrastructure as code, API gateways & traffic management, observability, or asynchronous processing tooling.
• Exposure to or interest in measuring and optimizing infrastructure cost and utilization
• Familiarity with high-volume data processing and storage systems, and with OLTP and OLAP databases.
• Experience with large scale data ecosystems — e.g., ClickHouse, DynamoDB MySQL, Kafka, Spark, Flink, Iceberg, or Airflow

What You'll Be Doing

• Ship foundational services to enable Klaviyo engineering to move faster with confidence.
• Build a deep understanding of engineering needs across the organization, guiding the design and development of appropriate platform primitives (Infra, Databases, Queuing, etc), that align with the platform's vision and practically empower product teams.
• Design, develop, and deliver software to dramatically improve the availability, scalability, latency, and cost efficiency of Klaviyo's core platforms, helping teams to better serve customers, operate within budget, and meet their SLOs.
• Design and develop systems and processes that enable highly available and scalable applications.
• Leverage technology such as Python, Go, AWS, and Kubernetes to advance Klaviyo's platform.
• Mentor and pair with other Klaviyo engineers to build better software by focusing on performance, self-healing systems, configuration as code, and defensive programming.
• Identify and drive cost-optimization opportunities across the platform — right-sizing infrastructure, improving resource utilization, and building tooling and guardrails that make cost efficiency the default for product teams.

Perks and Benefits

• Base salary range: €92,000 — €138,000 EUR
• Travel may be required up to 10%