Software Engineer II, Data Lake

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.

At Klaviyo, we love tackling tough engineering problems and look for engineers who specialize in certain areas but are passionate about building, owning & scaling features end to end from scratch and breaking through any obstacle or technical challenge in their way. We push each other to move out of our comfort zone, learn new technologies and work hard to ensure each day is better than the last.

Team Overview

Klaviyo operates a real-time and offline data analytics platform that is built for massive scale and hosted on Amazon Web Services (AWS). The DataLake team ingest billions of data points per day to power core, Klaviyo functionality and generate data-driven insights. These interactions are ingested from disparate sources, persisted into the Data Lake, materialized into analytical storage, and used to power AI models.

As an Engineer on the Data Lake Team, you will have ownership over defining the evolutionary, technical vision for our large-scale data processing systems. You will be responsible for designing, implementing, and optimizing mission-critical data pipelines and storage solutions, leveraging technologies like EMR, Spark, and Flink. You’ll work on ensuring scalability, performance, and reliability while mentoring team members and driving technical excellence.

Please note: this role is based in Boston, MA and requires a hybrid, in-office component.

• Python (Node or Java)
• Airflow
• MySQL
• AWS (including EMR, S3, Redshift)

How You'll Make a Difference

• Implement scalable, fault-tolerant data pipelines using distributed processing frameworks like Apache Spark and Flink on AWS EMR, optimizing for throughput and latency
• Design batch and real-time, event-driven data workflows to process billions of data points daily, leveraging streaming technologies like Kafka and Flink. - Optimize distributed compute clusters and storage systems (e.g., S3, HDFS) to handle petabyte-scale datasets efficiently, ensuring resource efficiency and cost-effectiveness.
• Develop robust failure recovery mechanisms, including checkpointing, replication, and automated failover, to ensure high availability in distributed environments
• Optimize data storage and processing systems to handle petabyte-scale datasets efficiently, ensuring performance and cost-effectiveness.
• Collaborate with cross-functional teams to deliver actionable datasets that power analytics and AI capabilities.
• Implement data governance policies and security measures to maintain data quality and compliance.
• Own the technical direction of highly visible data systems, improving monitoring, failure recovery, and performance.
• Mentor engineers, review technical documentation, and articulate phased approaches to achieving the team’s technical vision.
• Contribute to the evolution of internal data processing tools and frameworks, enhancing their scalability and usability

Must Have

• 4+ years of experience in software development, with at least 2 years focused on data engineering and distributed systems.
• Hands on with Python and SQL, with experience in backend development.
• Experience with distributed data processing frameworks such as Apache Spark and Flink.Proven track record of designing and implementing scalable ETL/ELT pipelines, ideally using AWS services like EMR.
• Strong knowledge of cloud platforms, particularly AWS (e.g., EMR, S3, Redshift), and optimizing data workflows in the cloud.
• Experience with data pipeline orchestration tools like Airflow.
• Familiarity with real-time data streaming technologies such as Kafka or Pulsar.
• Understanding of data modeling, database design, and data governance best practices.
• Excellent problem-solving skills and the ability to thrive in a fast-paced, collaborative environment.
• Strong communication skills with experience mentoring or leading engineering teams.
• Bachelor’s degree in Computer Science, Engineering, or a related field, or equivalent experience.
• 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.

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:

$120,000 — $180,000 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.

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).