Senior Lead Software Engineer

Background

Klaviyo operates a real-time data platform built for massive scale on Amazon Web Services (AWS). Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

We love tackling tough engineering problems and look for Engineers who specialize in certain areas but are passionate about building, owning & scaling features end to end from scratch and breaking through any obstacle or technical challenge in their way. We push each other to move out of our comfort zone, learn new technologies and work hard to ensure each day is better than the last. Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at

Area Overview

The Data Exchange area is responsible for collecting, distributing, and orchestrating data movement into and out of Klaviyo and between Klaviyo domains through a variety of protocols and delivery mechanisms. In addition, we provide other engineering teams and 3rd-party developers with infrastructure and tools to easily build data syncing workflows. On a daily basis, we handle billions of interconnected data points with a wide range of freshness, consistency, and interoperability requirements.

What You'll Do

• Define technical strategy within the scope of Data Exchange and execute to improve the area's architecture, products, infrastructure, and processes. Contribute to defining strategic direction, planning the roadmap, escalating issues, and synthesizing feedback to ensure team success.
• Lead the technical evolution of the area, overseeing multiple teams and ensuring alignment with your pillar objectives, company goals, and long-term strategy. Ensure technical designs are properly evaluated across multiple teams, provide and respond to thoughtful feedback across the organization to improve technical designs.
• Act as domain leader and the interface between a group of teams and the rest of the organization. Build relationships with stakeholders including customers, product managers, cross-functional partners, and external partners. Communicate the strategic direction and the rationale behind it to the entire organization.
• Strategize and execute independently and through others. Set direction for multiple teams in partnership with their managers. Manage and mitigate risks to plans.
• Mentor other engineers regularly, primarily experienced lead and senior engineers. Ensure others in the area are developing skills they need to improve within the organization.

Who You Are

• 12 years of experience in software development, strong knowledge of computer science fundamentals, domain-driven design, and extensive expertise in architectural patterns, specifically within the domain of distributed systems.
• Proven expertise in applying relevant design patterns to implementing highly-scalable multi-tenant systems.
• 8 years of experience testing, developing, and launching complex software products, and 5 years of hands-on experience in software design and system architecture, with a focus on reliability, fault-tolerance, and high performance.
• Demonstrated experience in contributing to the product and platform vision, as well as defining the strategy within the broader scope of long-term organizational needs.
• Exceptional communication skills, 4 years of experience disseminating a technical vision through multiple scrum teams and across the organization
• Solid foundation in data processing systems, experience with big data stack, and expertise in building stream/batch processing applications
• Familiarity with multi-dimensional data modeling, data change management, data warehousing, data governance concepts, and serverless data architectures.
• Experience mentoring seasoned engineers, focusing on leads and seniors with 7-12 years of experience.
• BA or BS Degree in Computer Science, related field, or equivalent experience.
• You've already experimented with AI in work or personal projects, and you're excited to dive in and learn fast. You're hungry to responsibly explore new AI tools and workflows, finding ways to make your work smarter and more efficient.

Our Tech Stack

• Python, Django, FastAPI
• Apache Kafka, Apache Pulsar, RabbitMQ, Spark, Airflow, and other tech from the big data stack
• MySQL, PostgreSQL, Clickhouse, Redis
• Typescript, React, Babel, Jest, Webpack
• Graphite, statsd, Grafana
• AWS, Terraform, Docker, Kubernetes, Pantsbuild, Jenkins, Argo, and other modern DevOps tools

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