KL

Sr. Software Engineer, Messaging Infrastructure

Klaviyo
Dublin, Irelandfull_timePosted 18 Jun 2026

About the role

<div class="content-intro"><p><em>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 <a class="_ymio1r31 _ypr0glyw _zcxs1o36 _mizu194a _1ah3dkaa _ra3xnqa1 _128mdkaa _1cvmnqa1 _4davt94y _4bfu18uv _1hms8stv _ajmmnqa1 _vchhusvi _kqswh2mm _ect4ttxp _syaz13af _1a3b18uv _4fpr8stv _5goinqa1 _f8pj13af _9oik18uv _1bnxglyw _jf4cnqa1 _30l313af _1nrm18uv _c2waglyw _1iohnqa1 _9h8h12zz _10531ra0 _1ien1ra0 _n0fx1ra0 _1vhv17z1" href="http://klaviyo.com/careers" data-renderer-mark="true">klaviyo.com/careers</a> to see how we empower creators to own their own destiny.</em></p></div><p><strong>About Klaviyo</strong></p> <p>Klaviyo is a leading marketing automation platform that helps businesses grow by delivering personalized experiences. Our mission is to empower creators to own their destiny. We believe in providing an exceptional developer experience that enables our engineering teams to build and ship high-quality software efficiently and with confidence.</p> <p><strong>About the Team</strong></p> <p>The Messaging Infra organization at Klaviyo is focused on high-growth customer engagement through various messaging channels (email, SMS/MMS/RCS, mobile push, WhatsApp, and more). We work with multiple stakeholders to provide best-in-class service and reliability to connect a wide range of businesses, from entrepreneurs to enterprises, with their end users. The messaging platform is a mission-critical system, responsible for delivering billions of messages, and must be architected for massive scale and reliability.<strong><br></strong><strong><br></strong><strong>How You Will Make a Difference </strong></p> <ul> <li>In this role, you will own and build features/services that hundreds of thousands of Klaviyo customers rely on daily to drive their business forward.</li> <li>Work on crafting our highly-scalable, highly-available campaign pipeline that processes and delivers hundreds of millions of messages daily growing to billions scale.</li> <li>Collaborate radically with teams and stakeholders across Klaviyo on designs, implementations, and engineering practices.</li> <li>Learn new technologies, bring them to the team and apply them to evolve our systems to the next level.</li> <li>Help us improve our experimentation and development processes, and mentor other engineers on the team.</li&gt

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Company

Klaviyo

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