Senior Software Engineer - Email Platforms

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 careers.klaviyo.com to see how we empower creators to own their own destiny.

Why You Should Join the Email Platforms Team:

The Email Platforms team at Klaviyo is building the next generation of infrastructure to support reliable, scalable, and performant email delivery. Our mission is to help Klaviyo reach enterprise scale by evolving and owning our email sending pipeline end-to-end. We're investing heavily in our homegrown email delivery infrastructure, giving us greater control, performance, and reliability in how we deliver emails for some of the largest brands in the world.

You’ll join a high-impact, high-ownership team tackling technical challenges around high-throughput systems, distributed messaging, and service performance at scale. Our work directly impacts customer satisfaction and business success. If you’re excited about email infrastructure, systems design, and high-scale backend development in Go, this is the role for you.

How You Will Make a Difference:

• Own and drive key components of the email pipeline architecture

• Design and implement scalable, high-throughput services in Go

• Develop systems that manage message queues and email delivery

• Help ensure our systems scale with customer growth, especially as we bring on larger enterprise accounts

• Collaborate cross-functionally to ensure the highest standards of performance, reliability, and deliverability

• Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up.

Who You Are:

• Senior-level backend engineer with strong systems design skills

• Proficient in Go (required). experience with Python is a plusExperienced working with high-throughput distributed systems

• Familiar with message queues (e.g., Pulsar, Kafka, RabbitMQ, SQS)

• Bonus: Experience with email infrastructure, MTAs, deliverability, or mailops

• Comfortable working independently on projects from design through production

• Able to thrive in a mostly remote team and deliver in a high-autonomy environment

• You’ve already experimented with AI in work or personal projects, and you’re excited to dive in and learn fast. You’re hungry to responsibly explore new AI tools and workflows, finding ways to make your work smarter and more efficient.

Technologies We Use:

• Languages: Go, Python

• Infrastructure: AWS, DynamoDB, Kubernetes, Terraform

Frameworks: Gin (Go), Django (Python)

• Messaging: Pulsar, Kafka, other message queues

• Email Systems: MTA’s (GreenArrow), Proxy servers, email deliverability tools, monitoring tools

We use Covey as part of our hiring and / or promotional process. For jobs or candidates in NYC, certain features may qualify it as an AEDT. As part of the evaluation process we provide Covey with job requirements and candidate submitted applications. We began using Covey Scout for Inbound on April 3, 2025.

Please see the independent bias audit report covering our use of Covey here

Massachusetts Applicants:
It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.

Our salary range reflects the cost of labor across various U.S. geographic markets. The range displayed below reflects the minimum and maximum target salaries for the position across all our US locations. The base salary offered for this position is determined by several factors, including the applicant’s job-related skills, relevant experience, education or training, and work location.

In addition to base salary, our total compensation package may include participation in the company’s annual cash bonus plan, variable compensation (OTE) for sales and customer success roles, equity, sign-on payments, and a comprehensive range of health, welfare, and wellbeing benefits based on eligibility.

Your recruiter can provide more details about the specific salary/OTE range for your preferred location during the hiring process.

Base Pay Range For US Locations:
$152,000—$228,000 USD

Get to Know Klaviyo

We’re Klaviyo (pronounced clay-vee-oh). We empower creators to own their destiny by making first-party data accessible and actionable like never before. We see limitless potential for the technology we’re developing to nurture personalized experiences in ecommerce and beyond. To reach our goals, we need our own crew of remarkable creators—ambitious and collaborative teammates who stay focused on our north star: delighting our customers. If you’re ready to do the best work of your career, where you’ll be welcomed as your whole self from day one and supported with generous benefits, we hope you’ll join us.

AI fluency at Klaviyo includes responsible use of AI (including privacy, security, bias awareness, and human-in-the-loop). We provide accommodations as needed.

By participating in Klaviyo’s interview process, you acknowledge that you have read, understood, and will adhere to our Guidelines for using AI in the Klaviyo interview Process. For more information about how we process your personal data, see our Job Applicant Privacy Notice.

Klaviyo is committed to a policy of equal opportunity and non-discrimination. We do not discriminate on the basis of race, ethnicity, citizenship, national origin, color, religion or religious creed, age, sex (including pregnancy), gender identity, sexual orientation, physical or mental disability, veteran or active military status, marital status, criminal record, genetics, retaliation, sexual harassment or any other characteristic protected by applicable law.

IMPORTANT NOTICE: Our company takes the security and privacy of job applicants very seriously. We will never ask for payment, bank details, or personal financial information as part of the application process. All our legitimate job postings can be found on our official career site. Please be cautious of job offers that come from non-company email addresses (@klaviyo.com), instant messaging platforms, or unsolicited calls.

By clicking "Submit Application" you consent to Klaviyo processing your Personal Data in accordance with our Job Applicant Privacy Notice. If you do not wish for Klaviyo to process your Personal Data, please do not submit an application. You can find our Job Applicant Privacy Notice here and here (FR).