Senior Software Engineer - Profiles, Identity, Consent at Klaviyo

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. Position Title: Senior Software Engineer About the Team: Profile data is the bedrock upon which Klaviyo’s entire product ecosystem is built. The Profiles, Identity, and Consent teams tackle massive distributed systems challenges, operating at a breathtaking scale—storing tens of billions of records and processing billions of reads and writes every single day. We own the highly available platform that defines "who" a customer is and "how" they can be reached. By partnering with data warehousing, segmentation, and messaging teams, you will architect the foundational data pipelines that power Klaviyo’s core product capabilities worldwide. Key Responsibilities: • Design and operate scalable distributed systems for identity resolution and consent • Collaborate cross-functionally to translate requirements into robust technical designs • Author technical design docs and service contracts for operational excellence • Participate in on-call rotations to continuously improve system reliability • Provide technical mentorship and conduct thoughtful code and design reviews • Delegate implementation to AI agents by defining clear intent and rigorously verifying outputs for security and correctness Required Skills: • 7+ years of software engineering experience with strong computer science fundamentals • Expertise in building backend service-oriented applications and REST/gRPC APIs • Hands-on experience scaling distributed systems for performance and consistency. • Proficiency with streaming and batch processing systems • Production experience with relational database schema design and optimization • Excellent communication skills for leading execution and driving team alignment • BA/BS in Computer Science, a related field, or equivalent practical experience • Expertise in agentic AI workflows to safely increase development throughput while preserving architectural coherence Team Tech Stack: • Languages: Python, SQL, Golang • Databases: Aurora MySQL, ProxySQL, Redis • Streaming and Batch: Apache Kafka, Pulsar, Spark, Iceberg • Infrastructure: AWS, Terraform, Docker, Kubernetes, Buildkite 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:$148,000—$222,000 USDGet 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).