Senior Software Engineer - Identity and Access Management

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

At Klaviyo, we value the different backgrounds, experiences, and perspectives that each Klaviyo brings to work. If you are close, but not an exact match, we hope you will still apply.

About the team

Identity and Access Management (IAM) controls how people, services, integrations, and AI agents access Klaviyo.

We build authentication and authorization for users, agents, and machines that access the Klaviyo platform.

This is a chance to solve hard identity problems that affect nearly every part of our product.

How you will make an impact

As a Senior Software Engineer, you will lead complex projects across several components while staying hands-on with the software. You will:

• Lead business-critical projects from design through launch and long-term operation.
• Build secure, reliable services for authentication, authorization, delegation, auditing, and revocation.
• Break ambiguous problems into clear work that several engineers can deliver together.
• Own the customer impact, reliability, and technical quality of your work in production.
• Improve the architecture of your area as scale, security, and product needs change.
• Define and maintain SLOs for the systems that you own.
• Partner with Security, Product, Platform, and product engineering teams.
• Create reusable patterns that make IAM easier and safer for other teams to adopt.
• Mentor engineers and help project contributors succeed.
• Apply new engineering and AI tools responsibly, then share what you learn with the team.
• Take on important unowned work that helps the team move faster.

Who you are

• You have 7+ years of experience building and operating production software.
• You have hands-on experience developing production services in Go or Python.
• You have experience with authentication, authorization, identity, or related security systems.
• You have built networking systems, API gateways, APIs, or SDKs.
• You have led complex projects that spanned multiple engineers and several months.
• You take end-to-end ownership and stay with your work after launch.
• You communicate clearly, work well across teams, and make practical technical decisions.
• You mentor other engineers and raise the quality bar through feedback and example.
• You balance long-term improvements with steady customer delivery.

Nice to have

• Experience with auth or policy systems.
• Experience building secure platforms used by other engineering teams.
• Experience with AWS, Terraform, Kubernetes, React, or Django.
• Experience with enterprise security, auditability, data residency, or compliance needs.

You do not need to know every part of our stack on day one. We care most about strong judgment, ownership, and care for the customer experience.

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.

This role may require up to 10% travel for purposes such as new hire onboarding, client or partner work if applicable, team meetings, and industry events. Travel is coordinated in advance.

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.