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Lead Software Engineer - SMS

  • Boston, MA
  • Engineering

At Klaviyo, we value the unique backgrounds, experiences and perspectives each Klaviyo (we call ourselves Klaviyos) brings to our workplace each and every day. We believe everyone deserves a fair shot at success and appreciate the experiences each person brings beyond the traditional job requirements. If you’re a close but not exact match with the description, we hope you’ll still consider applying. Want to learn more about life at Klaviyo? Visit to see how we empower creators to own their own destiny.

Why You Should Join the Messaging Channels Team :

As a Lead Software Engineer joining the Messaging Channels team you can expect to be deeply involved in technical discussions on how we scale our systems, roll out new features, and grow the team.

Channels Engineering works on high growth customer engagement through various messaging channels. The team works with multiple stakeholders to provide the best in class service and reliability to connect a wide range of customers, from entrepreneurs to enterprises, with their end users. The messaging platform for Klaviyo delivered over 25 Million messages during BFCM 2021 (Black Friday/Cyber Monday).

Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines. All engineers are expected to become extremely proficient in the technologies we use (not exhaustive): 

  • Python, Django, Celery
  • MySQL, Cassandra, RabbitMQ, Redis, Pulsar
  • React, HTML, JavaScript, Backbone.js
  • Amazon Web Services (EC2, RDS, Aurora, etc.), Fastly Cache, Kubernetes on EKS
  • Twilio, Sendgrid, Firebase, APNS

How You Will Make a Difference 

  • Build and improve systems for high volume message delivery using multiple engagement channels. 
  • Provide technical leadership to drive architectural decisions across multiple teams and provide solutions for complex problems around scalability, throughput, performance etc.
  • Strive towards a cohesive technical vision across multiple roadmap items that are built across multiple teams.
  • Be a technical point of contact for the team for various projects and features where there are dependencies. 
  • Define technical strategy within their scope and executes to improve the functional area's products, infrastructure, or processes.
  • Support Engineering Managers and Product Managers within the Organization from a technical point of view.
  • Mentor multiple engineers to develop new technical leadership for the company.

Who You Are 

  • Have 7+ years of experience and have architected, built and delivered at least one complex system.
  • Have multiple years of proven experience building products that matter and pushing yourself and your team to be better engineers and build a product with passionate advocates
  • Have proven that you can build & scale complex distributed systems including solving problems in sustainable ways, balancing pragmatic development with ideal architecture, breaking through technical obstacles with vigor, and leading teams through crises by working side by side with them in the trenches.
  • Enjoy working with new technologies ranging from the frontend to backend, and are particularly passionate and an expert in multiple stack areas. You show this by having strong and opinionated experience with various technologies and know how to pick the right tool for any job. 
  • Love digging into performance and scalability issues to drive breakthrough solutions--whether it's a slow loading UI or too many clicks in a workflow, a database query timing out, or a queue that just won’t drain. You recognize all problems can be solved.
  • Enjoy shipping code early & often in an agile fashion, pairing with product management to craft better software by soliciting feedback from thousands of end users. 
  • Like working on small, autonomous agile teams. At Klaviyo, you will have ownership of features, but you'll collaborate with everyone to make sure we produce the right solution.

Get to Know Klaviyo

Klaviyo is a world-leading marketing automation platform dedicated to accelerating revenue and customer connection for online businesses. Klaviyo makes it easy to store, access, analyze and use transactional and behavioral data to power highly-targeted customer and prospect communications. The company's hybrid customer-data and marketing-platform model allows companies to grow by fostering direct relationships with customers, without giving up their valuable data to popular big-tech ad platforms. Over 265,000 innovative companies like Unilever, Custom Ink, Living Proof and Huckberry sell more with Klaviyo. Learn more at .

If you are a Colorado or New York City resident and this role is a remote role, you can receive additional information about the compensation and benefits for this role, which we will provide upon request. Requests can be submitted here . Additional information regarding benefits can be found here .

Klaviyo is committed to diversity and to a policy of equal employment opportunity and non-discrimination. We do not discriminate on the basis of race, color, religion, national origin, age, sex, marital status, ancestry, physical or mental disability, veteran status, gender identity, sexual orientation or any other characteristic protected by applicable law.

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