Klaviyo

Klaviyo is a data science company that helps brands grow faster. We’re profitable, engineering-driven and growing incredibly fast. We have over 12,000 paying customers and are doubling year over year and ingesting an order of magnitude more data every year. We run a DevOps culture and love full stack engineers who code in both Python and Javascript (we use React and TypeScript). Our tech stack is predominantly Python (Django), Java and JS/React running on AWS at massive scale. We run thousands of EC2 boxes, 100s of Aurora MySQL and PostgreSQL clusters and petabyte scale Cassandra clusters. We’re heavy users of Kafka, RabbitMQ and Redis. We’ve just recently launched our first workloads on Kubernetes. We send billions of emails every month and fire customers that send spam--our goal is helping customers have more effective long-term relationships with their customers. We also do push notifications, website personalization and soon SMS. We recently raised one of the largest fund-raising rounds in Boston history ($150m) but don’t intend to change our core values which includes growing our business organically.