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.

Email Engineering has direct technical responsibility for Klaviyo’s most-used engagement channel. Our systems send over 500M emails each day, and drive billions of dollars of revenue for Klaviyo customers. Our technical ownership stretches all the way from the email sending and tracking infrastructure, to high-reliability and high-performance asynchronous services, and ultimately to the user-experience where customers configure and analyze their campaigns.

To support and help drive Klaviyo’s rapid growth (2x per year the past several years) the team is initiating a major project to deploy and operate an MTA installation that will eventually become Klaviyo’s centerpiece email-sending option. The target for this system is billions of emails per day with global presence. 

How You Will Make a Difference 

  • Architect and implement a world-class email sending service that equals and exceeds performance of market-leading ESPs.
  • Be a leader on a team dedicated to all aspects of message sending and tracking operations, including: deliverability, maintaining compliance with relevant global regulations and standards, SLOs/SLAs, system reliability and scale.
  • Evangelize and educate other Klaviyos on all things email sending and deliverability.
  • Collaborate with teams across Klaviyo on design, integration and operation of email sending services.
  • Mentor engineers and analysts. Assist with team growth and development through technical interviewing.
  • Contribute to Klaviyo strategy by developing options and plans that align with company worldwide growth.

Who You Are 

  • Have 6+ years of email systems experience: SMTP, POP, SPF, DKIM, DMARC, RBL, CAN-SPAM.
  • Have led design and implementation of a high-scale / high-reliability MTA deployment; specific hands-on experience with at least one MTA solution, PowerMTA preferred. 
  • Have strong knowledge of email deliverability, IP reputation, blocklists.
  • Have experience with deployment and in structure management tools, such as : Terraform, Chef, Ansible, Jenkins.
  • Have experience with cloud-first monitoring, logging, and alerting infrastructure that support 24/7 enterprise platforms.
  • 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

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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At Klaviyo, we strive to make the world more equitable - it’s one of our core values. Klaviyos (our employees) believe that everyone deserves a fair shot at success. We strive to be a diverse company, where we seek opinions and experiences different from our own. Individuals seeking employment at Klaviyo are considered without regard to 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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