Senior Software Engineer, Full Stack

At Klaviyo, 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 operates a real-time data platform written in Python and 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 are seeking a frontend-leaning full-stack Senior Software Engineer who is passionate about using cutting-edge open source frameworks with emerging technologies. You’ll have the opportunity to be on the forefront of driving a major transformation within Klaviyo.

Technologies we use (not exhaustive):

• React, Typescript, Webpack, Fastly
• Python, Django
• RabbitMQ, Celery, Kafka, Apache Pulsar
• MySQL, Redis, Memcached
• Graphite, statsd, Grafana
• AWS, Kubernetes, Terraform, Docker, Jenkins, and other modern DevOps tools

How You'll Make a Difference

• Own customer-facing features that tens thousands of our customers rely on daily to reach 4B+ of consumers to drive their business forward
• Lead the development of customer-facing components in complex distributed data processing systems
• Work with a team of developers with deep experience in distributed microservices and full stack systems
• Own the technical design and development of cross-functional, multi-platform application systems
• Establish expertise in multiple internal and industry practices, patterns, tools, languages, and processes
• Lead and mentor engineers within your organization on frontend best practices

Who You Are

• Be proficient in both frontend and backend
• Extensive frontend engineering experience
• Experience working in React
• Experience developing application APIs (e.g. REST, GraphQL, JSON Schema, or JSON:API, etc.)
• Experience working with distributed systems is preferred
• Experience working with cloud technologies (AWS, GCP, Azure, etc.)
• Experience with custom frontend build systems + tooling (e.g. Webpack, Babel, TypeScript, ESLint, Jest, Jenkins, CDNs, etc.)
• Having established best practices in how a company writes, tests, and deploys frontend code
• Enjoy working on small, autonomous agile teams. 
• Enjoy shipping code early and often in an agile fashion, pairing with product management, business stakeholders, and other engineers to craft better software.