Senior Software Engineer, Recommendations 

Boston, MA (Hybrid)

What you'll do

As the Senior Software Engineer for Product Recommendations, you will be a key contributor in building the machine learning–powered systems that decide which products to show to whom and when across all channels powered by our platform. This hands-on backend role focuses on converting billions of behavioral events into personalized product recommendations that drive revenue for merchants. You will define technical direction, build, and operate services and data pipelines end to end, from data ingestion and feature generation to ranking models and APIs.

• Lead the design, architecture, and operation of backend services that power product recommendations across Klaviyo experiences (email, SMS, KAgent, onsite, etc.), upholding standards for reliability, performance, and clear APIs.
• Architect and maintain robust, large-scale data processing pipelines (e.g., using Apache Spark or similar frameworks) that transform raw events and catalog data into high-quality features and inputs for recommendation models, ensuring data quality and lineage.
• Collaborate closely with ML engineers and product stakeholders to strategically productionize recommendation models—defining high-level interfaces, robust feature contracts, and advanced deployment patterns for batch and/or real-time inference systems.
• Drive the development of ML/AI systems such as vector search that power recommendation, semantic search, and sophisticated agentic use cases.
• Implement and evolve data and service observability (metrics, logging, tracing, dashboards) to proactively ensure recommendations are correct, fast, and highly available for all customers.
• Contribute to and mentor others on shared data frameworks, libraries, and architectural patterns to accelerate the development of new recommendation use cases and iteration velocity across the team.
• Work with Product to break down projects into clear milestones, balancing the need for rapid experimentation with technical soundness and long-term maintainability.
• Lead data-driven decision making and A/B testing efforts—ensuring recommendation systems are instrumented with the right metrics, and independently interpreting results to guide future product and engineering iterations.
• Participate in on-call and incident response for the systems you own, driving major post-incident follow-ups that substantially improve the resilience and operability of our recommendation stack.
• Champion and drive the transformation of engineering workflows by integrating AI from the ground up—for example, using AI to accelerate development, automate complex tests, or build smarter monitoring and debugging tools.
• Share knowledge, mentor junior/mid-level engineers, and define best practices on working with large-scale data frameworks, distributed systems, and integrating ML into production systems.

Who you are

• 5+ years of software engineering experience, with experience building and operating mission-critical backend services and systems in a production environment.
• Experience in backend and distributed systems at scale; you have a proven track record working on high-throughput, highly available services and are an skilled in optimizing for latency, reliability, and operability.
• Proficient in Python and open to working in other languages
• Comfortable with cloud-native architectures (AWS preferred) and container orchestration (e.g., Kubernetes); you manage infrastructure and CI/CD pipelines as a core part of your development process.
• Experience in data-driven decision making and A/B testing—you can define how to instrument experiments, read and interpret results, and ensure learnings are folded back into system design.
• Comfortable designing and querying data models in relational, analytical, and NoSQL datastores (e.g., Postgres, MySQL, data warehouses, Redis, vector databases).
• Feel at home with modern DevOps practices (CI/CD, monitoring, alerting) and how to apply them to architect large-scale data and recommendation systems.
• Track record of owning multi-component projects end-to-end—from initial technical design and implementation through rollout, monitoring, and sustained iteration.
• Excellent technical collaborator and communicator: you can clearly articulate complex technical trade-offs to both technical peers and non-technical partners, and you work effectively to drive alignment across ML Engineers, Software Engineers, PMs, and other teams.
• You are a self-starter who has actively experimented with AI in work or personal projects and are excited to responsibly explore and define new AI tools and workflows to enhance team productivity and system intelligence.

Nice to have

• Previous experience working on product recommendation systems or adjacent ML-powered features (ranking, personalization, search, or similar).
• Experience with big data frameworks such as Apache Spark (or similar technologies like Flink, Beam, etc.) for architecting and building complex batch or streaming pipelines.
• Experience in AI/ML systems and products, such as integrating models into production systems, building features powered by ML, or contributing to the ML infrastructure.
• Experience training and iterating on machine learning models (e.g., for ranking, prediction, or personalization).
• Experience with ML and distributed compute frameworks such as Ray or similar tools.
• Experience partnering with data science or ML teams to productionize models (designing feature stores, ensuring offline/online parity, advanced model deployment and monitoring).
• Background in e-commerce, marketing tech, or consumer personalization products.

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

Software Engineer II - Analytics Data Engineering | AI & Analytics Data Enablement

Location: Boston, MA

About the Role

Data is the lifeblood of Klaviyo. As a Data Engineer on this team, you will sit at the intersection of infrastructure and intelligence. You won’t just be moving data; you’ll be building the foundations that power our next generation of AI-driven features and enterprise-scale analytics.

You will bridge the gap between data engineering and product impact. Your work will involve developing scalable Spark pipelines, tuning our storage and query patterns to ensure low-latency performance for our enterprise customers, and modeling the high-impact datasets that drive Klaviyo's analytics and machine learning engines.

What You’ll Do

• Build Production-Grade Foundations: Develop and maintain scalable data pipelines and core tables using PySpark, Airflow, and dbt. You will implement the foundational datasets that power our AI, ML, and Analytics products.
• Optimize for Enterprise Performance: Tune Spark jobs and storage patterns to ensure low-latency data retrieval. You will help implement materialized views and efficient partitioning strategies to support high-performance reporting at scale.
• Treat Data as a Product: Contribute to the full lifecycle of datasets. This includes defining clear data contracts with upstream teams, writing maintainable code via peer reviews, and ensuring every asset is well-documented and trusted by downstream users.
• Drive Operational Excellence: Ensure the reliability of our data engine by monitoring for freshness, volume anomalies, and schema changes. You will be responsible for ensuring that when a customer loads a dashboard, the data is accurate and on time.
• Partner Cross-Functionally: Collaborate with Product, Engineering, and AI/ML teams to define consistent metrics that align with business goals. You will act as a bridge to ensure new features land with robust data support.
• Innovate with AI: Look for opportunities to put AI at the center of your workflow, whether it is using AI to generate tests, detect data anomalies, or accelerate complex analysis.

Who You Are

• The Experience: 2+ years of experience in data engineering or a data-intensive software engineering role. You’ve moved past the "beginner" phase and are comfortable taking a project from a design doc to a production deployment.
• Fluent in SQL and Python: You have a solid grasp of SQL for high-performance querying and are comfortable using Python for data manipulation and automation. You focus on writing code that balances speed with reliability.
• Distributed Systems Knowledge: You have hands-on experience with Spark (PySpark/SparkSQL) and understand how to tune jobs for performance in a cloud environment (AWS/EMR).
• Modeling Intuition: You understand the difference between a "raw table" and a "semantic layer." You’ve worked with modern modeling tools (like dbt) and understand partitioning, schema evolution, and lakehouse concepts (Iceberg/Delta).
• Performance Minded: You care about latency. You enjoy the challenge of making a query run faster and understand how to use materialized views and caching effectively.
• Collaborative & Curious: You’re an inclusive collaborator who enjoys working with Product and Data Science. You’re excited to experiment with AI tools to make your own engineering workflow more efficient.

Nice to Haves

• Experience with Iceberg table maintenance and compaction.
• Exposure to Terraform or other Infrastructure-as-Code tools.
• A background in Martech or SaaS platforms dealing with high-frequency event data.
• Experience building data products that directly power customer-facing UI components and/or support AI/ML features.
• Experience building near real-time or streaming pipelines for user-facing analytics or monitoring.
• Hands-on work with analytics engineering tools and practices (e.g., dbt, metrics layers, semantic models).
• Familiarity with statistical modeling and machine learning.

SWE II, Core Reporting (Boston, MA) 

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.

Klaviyo operates a real-time data analytics platform coded primarily in Python that is built for massive scale. Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

The Core Reporting Team is responsible for powering Klaviyo’s analytics foundation.  We deliver scalable, consistent, and trustworthy reporting infrastructure that enables every team at Klaviyo to ship analytics faster - and every customer to understand, trust, and act on their data. The team builds curated and customizable reporting experiences that serve all of Klaviyo’s customers. The team collaborates closely with Product, Design, and cross-functional partners across Klaviyo to ensure that insights are not just observed but operationalized, connecting analytics directly to action. 

As an Engineer on the Core Reporting Team, you can expect to be deeply involved in the technical strategy behind how we access, aggregate, and present data at scale across the Klaviyo platform. You'll own projects that contribute to driving adoption and retention of the analytics platform, building the reporting capabilities that are a key reason customers purchase and expand with Klaviyo. You'll work full stack, from the data access and storage layers that power enterprise-grade analytics, to the front-end experiences that make complex data intuitive and actionable. Your tech stack will include Python, TypeScript, React, AWS, and Django.

How You Will Make a Difference

• Deliver reporting capabilities that drive adoption and directly contribute to growth
• Build experiences that close the loop from insight to action, enabling customers to create segments, campaigns, and flows directly from reporting surfaces.
• Develop product-led experiences that make the value of Analytics visible and compelling.
• Work cross-functionally with Product, Design, Data Science, and partner engineering teams to shape the roadmap and technical direction of analytics at Klaviyo
• Have ample opportunities for growth as the team expands its scope across enterprise portfolio analytics, AI-assisted exploration, and agentic integrations

Who You Are

• 2+ years of experience working in a in a full stack capacity
• Proficient in at least one modern programming language (Python or TypeScript/React are a plus)
• Degree or equivalent experience in a software engineering discipline
• Able to communicate well and collaborate effectively across disciplines
• Able to work with others on a team and partner closely with product, design, and data stakeholders
• Able to learn continuously and adapt to a high-growth environment
• Able to stick with and solve difficult problems, particularly around data at scale
• Excited to work at the intersection of data visualization, analytics, and AI. Building experiences that help customers understand and act on their data
• Interested in up-market product challenges, including enterprise-grade reliability, and customization.

Technologies We Use (non-exhaustive)

• Front-end technologies like TypeScript, React, Styled Components, and CSS
• Backend primarily using Django, FastAPI, and Python
• Infrastructure on AWS and Kubernetes

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

Klaviyo is growing fast, and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech.

We love tackling tough engineering problems and look for engineers who specialize in certain areas but are passionate about building, owning, and scaling features end to end — 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.

Location:
This position is based in our Boston office, and team members are expected to be onsite at least three days per week.

Our Stack and Culture:
Klaviyo operates a real-time data platform coded in Python, built for massive scale on Amazon Web Services (AWS). Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

Team Overview:
The API team empowers product development teams at Klaviyo to create consistent, reliable, and developer-friendly public and internal APIs by providing robust frameworks, intuitive tools, and expert support.

Areas of ownership include:

• Public API Framework: Building consistent, reliable, and performant public APIs.

• Internal API Platform: A standardized platform for building, deploying, and consuming internal APIs to accelerate development and improve reliability.

• Encoded Objects: Standardized data schema definition and serialization framework ensuring consistency and compatibility across systems.

• API Rate Limiter: System enforcing request limits to protect API reliability and performance.

Responsibilities:

• Contribute to the evolution of Klaviyo’s public and internal API platforms.

• Participate in code reviews, product specifications, and scope definition.

• Collaborate with product owners and engineering peers to deliver high-quality, scalable solutions.

• Influence the direction and priorities of the API team.

Required Skills:

• 3–5+ years of experience in software engineering.

• Experience working with both monolithic and microservices architectures.

• Experience with CI/CD pipelines.

• Strong debugging and performance optimization skills.

Team Tech Stack:
Python, Django REST Framework, Django, FastAPI
MySQL / PostgreSQL, DocumentDB, ClickHouse
Redis, Memcached, RabbitMQ / Celery / Apache Pulsar

Preferred Skills:

• Experience with metaprogramming.

• Experience with Go.

• Familiarity with JSON:API.

• Experience designing and building internal or public APIs.

• Experience with Service-Oriented Architecture (preferably in Python).

• Experience working with RESTful applications, APIs, or gRPC.

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

Why you should join the Mobile App Growth team

The Mobile App Growth team, a diverse group of accomplished engineers, focuses extensively on developing new, greenfield projects within the mobile application domain. Their work is cross-functional, spanning various mobile platforms, and includes developing full-stack solutions to support product features exposed to mobile users via our SDKs.

Over the past year, the Mobile App Growth team at Klaviyo has introduced new mobile-first features (like geofencing and in-app forms) and enhanced Klaviyo’s mobile integration offerings. This expansion has augmented the scope of the team’s responsibilities. With new products to cultivate and integrations to support, the team requires a highly capable software engineer to help manage the increasing demands within Klaviyo's mobile ecosystem.

This engineer will contribute to the expansion and maintenance of the team’s mobile SDK offerings, furthering current product features and extending Klaviyo’s reach beyond traditional email marketing into comprehensive mobile engagement.

How You'll Make an Impact

• You will be a core member of the Mobile App Growth team, working on impactful mobile experiences making mobile integrations a core pillar of Klaviyo’s offerings
• Work closely with product to provide the best experience for our customers.
• Take ownership of projects from inception to release.
• Work across different mobile technologies
• Work in the Django framework to help build out a pipeline for rendered mobile experiences. 

Who you are

Deep experience modern mobile development (either Android, iOS or cross-platform experience) 

• Open to working with different technologies: Python, React, AWS, GoLang (prior experience not required but nice to have)
• Have a proven track record of leading projects and collaborating well with the wider team
• Experience working with mobile webviews and location services.
• Comfortable leveraging AI technologies effectively in personal contributions.
• Self-starter - As the member of the team, we are looking for someone who can bring with them expertise in mobile development.
• Adaptability - We will be working not just in native SDKs but also backend and frontend Klaviyo stacks, dev tooling and possible expansion into tertiary SDKs in the future.
• Ambition - We are looking for people that can take an idea and have the ambition to headline it in the future.
• Learning - To be always learning is a core value at Klaviyo and this role will require someone excited to learn new technologies and expose themselves to new approaches

Technologies We Use (not exhaustive)

• iOS (Swift)
• Android (Kotlin)
• React Native
• Flutter
• React, TypeScript, Redux
• Python, Django
• MySQL, Redis, DynamoDB
• AWS (EC2, RDS, Aurora), Terraform

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

Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech

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.

Klaviyo operates a real-time data platform built for massive scale on Amazon Web Services (AWS). Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

Responsibilities

The teams in the Data Platform area work with large scale distributed systems and databases to power core Klaviyo functionality and generate data-driven insights. As an engineer in this area, you will be responsible for designing, building, and maintaining systems that support other engineering teams across Klaviyo. You will work with a cross functional team to help design systems, write high quality code, create infrastructure, and operate large scale systems in a production environment.

Team Tech Stack

• AWS
• Python
• Kubernetes
• MySQL
• Clickhouse
• Kafka
• Spark
• Flink
• Iceberg
• Terraform
• Airflow

Required Skills

• Degree or equivalent experience in a software engineering discipline
• 2+ years of experience in a software engineering discipline
• Proficient in using at least one modern programming language
• Experience designing, building, and operating distributed systems in a cloud computing environment
• Experience with OLTP or OLAP databases
• Experience with high volume data processing and storage systems
• Experience provisioning infrastructure using Terraform or a similar infrastructure as code tool
• Experience using Linux operating systems
• Able to communicate well
• Able to work with others on a team
• Able to learn continuously and adapt to a high growth environment
• Able to stick with and solve difficult problems

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

SWE II, Advanced Reporting (Boston, MA Hybrid)

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.

Klaviyo operates a real-time data analytics platform coded primarily in Python that is built for massive scale. Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

The Advanced Reporting Team is responsible for delivering enterprise-grade, AI-powered analytics that help sophisticated brands understand their business, make confident decisions, and take action, all directly inside the Klaviyo platform. The team builds curated and customizable reporting experiences that serve all of Klaviyo’s customers with complex data, multiple channels, and advanced analytical needs. The team collaborates closely with Product, Design, and cross-functional partners across Klaviyo to ensure that insights are not just observed but operationalized, connecting analytics directly to action.

As an Engineer on the Advanced Reporting Team, you can expect to be deeply involved in the technical strategy behind how we access, aggregate, and present data at scale across the Klaviyo platform. You'll own projects that contribute to driving adoption and retention of Marketing Analytics, building the reporting capabilities that are a key reason customers purchase and expand with Klaviyo. You'll work full stack, from the data access and storage layers that power enterprise-grade analytics, to the front-end experiences that make complex data intuitive and actionable. Your tech stack will include Python, TypeScript, React, AWS, and Django.

How You Will Make a Difference

• Deliver advanced reporting capabilities that drive adoption and directly contribute to growth
• Build experiences that close the loop from insight to action, enabling customers to create segments, campaigns, and flows directly from reporting surfaces.
• Develop product-led experiences that make the value of Marketing Analytics visible and compelling.
• Work cross-functionally with Product, Design, Data Science, and partner engineering teams to shape the roadmap and technical direction of analytics at Klaviyo
• Have ample opportunities for growth as the team expands its scope across enterprise portfolio analytics, AI-assisted exploration, and agentic integrations

Who You Are

• 2+ years of experience working in a in a full stack capacity
• Proficient in at least one modern programming language (Python or TypeScript/React are a plus)
• Degree or equivalent experience in a software engineering discipline
• Able to communicate well and collaborate effectively across disciplines
• Able to work with others on a team and partner closely with product, design, and data stakeholders
• Able to learn continuously and adapt to a high-growth environment
• Able to stick with and solve difficult problems, particularly around data at scale
• Excited to work at the intersection of data visualization, analytics, and AI. Building experiences that help customers understand and act on their data
• Interested in up-market product challenges, including enterprise-grade reliability, and customization.

Technologies We Use (non-exhaustive)

• Front-end technologies like TypeScript, React, Styled Components, and CSS
• Backend primarily using Django, FastAPI, and Python
• Infrastructure on AWS and Kubernetes

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

Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech

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.

Klaviyo operates a real-time data platform built for massive scale on Amazon Web Services (AWS). Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

Responsibilities

The Data Automation team builds tooling that helps our Data Platform engineers provision and test infrastructure to power core Klaviyo functionality and generate data-driven insights. As an engineer on this team, you will be responsible for designing, building, and maintaining systems that help us operate our mission critical analytics infrastructure. You will work with a cross functional team to help design systems, create infrastructure, write high quality code, and operate large scale systems in a production environment.

Team Tech Stack

• AWS
• Python
• Terraform
• Kubernetes
• Clickhouse
• DynamoDB
• MySQL
• Kafka
• Spark
• Flink
• Iceberg
• Airflow

Required Skills

• Degree or equivalent experience in a software engineering discipline
• Proficient in using at least one modern programming language
• Able to communicate well
• Able to work with others on a team
• Able to learn continuously and adapt to a high growth environment
• Able to stick with and solve difficult problems
• 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.

Preferred Skills

• Experience designing, building, and operating distributed systems in a cloud computing environment
• Experience provisioning infrastructure using Terraform or a similar infrastructure as code tool
• Experience performance tuning and scaling systems
• Experience with OLTP and OLAP databases
• Experience with high volume data processing and storage systems
• Experience using Linux operating systems

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

Why You Should Join the Mobile Channels Team:

The Mobile Channels team at Klaviyo powers text messaging across Klaviyo's platform — SMS, RCS, WhatsApp, and a growing set of future text messaging channels. As brands increasingly rely on mobile to reach their customers, our team builds the infrastructure that makes high-throughput, reliable delivery possible across a complex, multi-channel landscape. We own the systems that connect Klaviyo customers to their audiences through the fastest and most personal communication channels available.

As a Lead Software Engineer on the Mobile Channels team, you'll provide technical leadership to a group of engineers building and scaling the services that power Klaviyo's mobile messaging pipeline end-to-end. You'll drive technical strategy, own critical components of the delivery infrastructure, and help the team navigate the unique challenges of multi-channel compliance, carrier regulations, provider integrations, and global deliverability. This is a hands-on technical leadership role where you'll contribute to architecture, code, and mentorship while shaping the future of mobile messaging at Klaviyo.

If you're excited about building systems that deliver millions of messages across channels with speed and reliability — and leading a team at the center of one of Klaviyo's fastest-growing product areas — Mobile Channels is the place to do it.

How You Will Make a Difference:

• Lead a team of engineers building and scaling Klaviyo's mobile messaging infrastructure across SMS, RCS, WhatsApp, and future channels
• Own and drive the architecture of key components in the mobile messaging pipeline — from message ingestion and routing to provider delivery and status tracking
• Design and implement scalable, high-throughput services in Python and Go
• Build systems that ensure reliable delivery at scale while managing carrier compliance, opt-in/opt-out requirements, throughput limits, and international messaging regulations
• Contribute directly to architecture and code, driving best practices and quality
• Collaborate cross-functionally with product, deliverability, compliance, and platform teams to expand mobile channel capabilities
• Grow and mentor engineers while helping shape the future of mobile messaging at Klaviyo
• Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up

Who You Are:

• 8+ years of engineering experience with strong backend and systems design skills
• Proficient in Python and/or Go and be able to rapidly learn the other
• Comfortable coding and reviewing complex systems — this is a hands-on role
• Experienced working with high-throughput distributed systems
• Skilled in system design and scaling infrastructure using AWS
• Strong business and product mindset — you think beyond the code to understand customer impact and commercial value
• Able to bring clarity to ambiguous requirements, breaking down undefined problems into actionable plans
• Self-led and driven to deliver incrementally — you ship value early and iterate
• Bonus: Experience with SMS/MMS infrastructure, RCS, WhatsApp Business API, carrier integrations, telecom APIs, or messaging compliance
• Clear communicator and collaborative team player
• Able to thrive in a hybrid 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:

• Python, Go
• AWS, Terraform, DynamoDB, Redis, SQL
• Kafka

Location:

This is a hybrid role based in Boston, with 3 days in office and 2 days remote per week.

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

Why You Should Join the Mobile Channels Team:

The Mobile Channels team at Klaviyo powers text messaging across Klaviyo's platform — SMS, RCS, WhatsApp, and a growing set of future text messaging channels. Mobile is one of Klaviyo's fastest-growing product areas: as brands shift more of their owned-channel investment to mobile, our team builds the infrastructure that makes high-throughput, reliable delivery possible across a complex, multi-channel landscape. We own the systems that connect Klaviyo customers to their audiences through the fastest and most personal communication channels available — at scale, across geographies, and against a constantly evolving set of carrier, regulatory, and provider constraints.

As a Senior Lead Software Engineer on the Mobile Channels team, you'll be the technical area lead for Mobile Channels — driving architecture and technical direction across the SMS, RCS, and WhatsApp teams, and the new channels we'll add next. You'll define the cross-team technical roadmap for the pillar, own the architectural patterns that bind the channels together (ingestion, routing, provider integration, status tracking, compliance automation, deliverability), and lead the most complex, multi-team initiatives end-to-end. This is a hands-on technical leadership role: you'll contribute to architecture and code, lead design reviews, mentor Lead and Senior engineers across multiple teams, and partner closely with Engineering Managers to keep our systems healthy as the surface area grows.

If you're excited about being the senior IC who connects the technical strategy across an entire multi-channel messaging pillar — and doing it at one of Klaviyo's highest-growth product areas — Mobile Channels is the place to do it.

How You Will Make a Difference:

• Technical Strategy & Roadmap: Define and drive the cross-team technical roadmap for Mobile Channels, aligning architectural direction across SMS, RCS, WhatsApp, and emerging channels with company priorities and the broader Messaging Infrastructure strategy.
• Multi-Team Architecture: Own the architectural patterns that span the pillar — message ingestion and routing, provider integration, status tracking, deliverability, opt-in/opt-out and compliance automation, multi-region readiness — and embed them into team roadmaps, not just documents.
• Hands-On Technical Leadership: Stay in the code. Drive architecture and design across teams, lead high-stakes design reviews, build prototypes and reference implementations to de-risk decisions, and ship meaningful contributions yourself.
• Reliability & Scale: Raise the bar on reliability across Mobile Channels — drive systemic fixes for recurring incidents, lead deep dives on the highest-impact production issues, and embed stronger guardrails (end-to-end testing in CI, readiness gates, observability standards) into how the teams ship.
• Cross-Functional & Cross-Pillar Collaboration: Partner with Engineering Managers, Product, Deliverability, Compliance, and Platform leadership to sequence cross-team work realistically. Build durable peer relationships with senior technical leaders across Klaviyo's other engineering pillars to drive company-wide technical objectives that span multiple pillars — bringing the Mobile Channels perspective to those forums, and connecting our roadmap to the broader engineering strategy.
• AI-Forward Engineering: Put AI at the center of how the teams build and how the systems run — model AI-fluent engineering practices yourself, and drive concrete improvements to operational and developer workflows (anomaly detection, synthetic load, runbook automation) across the teams.
• Mentorship: Mentor other engineers regularly, primarily experienced lead and senior engineers across SMS, RCS, and WhatsApp, and represent Mobile Channels' technical bar in senior hiring.
• Continuous Improvement: Stay current with how the messaging ecosystem and engineering craft are evolving — new channels, carrier and regulatory shifts, AI tooling, performance and reliability practices — and translate that into concrete, sequenced improvements for the teams.

Who You Are:

• Experience: 12+ years of software engineering experience with a strong track record building and scaling distributed backend systems. Prior time as a Lead, Staff, or Principal engineer driving technical direction across multiple teams.
• Hands-On Technical Depth: Proficient in Python and/or Go, and able to rapidly learn the other. Comfortable coding, reviewing, and debugging complex systems — this is a hands-on role.
• Distributed Systems Expertise: Deep experience with high-throughput, event-driven, distributed architectures — ingestion pipelines, async processing, stateful workloads, eventing patterns, multi-region/data-locality concerns, and the failure modes that come with all of it.
• Architectural & Strategic Skills: Demonstrated ability to define technical strategy and drive cross-team architectural decisions in ambiguous, high-stakes environments — and to commit to a call even when there's disagreement, backed by data and prototypes.
• Cloud & Platform: Strong experience with AWS at scale; comfortable with Infrastructure as Code (Terraform), containerization, and modern observability stacks (metrics, logs, traces, SLI/SLO design).
• Business & Product Mindset: You think beyond the code — you understand customer impact, commercial value, and the cost-vs-conversion tradeoffs that come with mobile messaging — and you bring that mindset into architectural decisions.
• Influence & Communication: Exceptional communicator; can articulate complex technical concepts to engineers, product leaders, and executives, and can rally multiple teams toward sequenced, realistic improvements.
• AI Enthusiast: 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 — and the systems you build — smarter and more efficient.
• Collaborative & Self-Led: Strong cross-functional partner; thrives in a hybrid team and high-autonomy environment; ships value early and iterates.

Nice to Have:

• Experience with the SMS, RCS, or WhatsApp ecosystems, including channel-specific protocols, opt-in/opt-out semantics, and familiarity with key 3rd-party entities (carriers, providers, regulators) and compliance rules and best practices.
• Background in performance optimization and a passion for digging into performance, scalability, and reliability issues to drive breakthrough solutions across distributed systems.
• Experience with multi-region deployments, data residency, and large-scale data or service migrations with minimal downtime.
• Familiarity with complex data management for testing, including large datasets and production-like data replication.

Technologies We Use:

• Python, Go
• AWS, Terraform, DynamoDB, Redis, SQL
• Kafka

Location:

This is a hybrid role based in Boston, with 3 days in office and 2 days remote per week.

At Klaviyo, we believe the future of software lies not in productivity tools for human users but in software that can run and optimize itself based on outcome or reward metrics. We’ve built the infrastructure and application that serve as the interface between businesses and consumers. We now have over 167,000 customers, billions of consumer profiles, and hundreds of billions of customer messages and follow-on conversion data. We are building state-of-the-art AI and machine learning technologies at Klaviyo to power marketing agent, service agent, and personalization products such as smart send time, audience optimization and product recommendations.

As a Machine Learning Platform Engineering Manager, you will lead a team of engineers building the core platforms, tools, and infrastructure that ML and AI engineers rely on to create advanced agents and models powering Klaviyo’s products. Your team will own platforms for training and deploying models and scaling systems that must operate reliably at Klaviyo’s data and traffic scale.

This is a backend-heavy, hands-on technical leadership role. You will manage and grow engineers, shape the technical roadmap for ML Platform, and collaborate closely with product, ML, data science, and infrastructure partners to deliver durable, high-leverage platforms that accelerate AI development across Klaviyo.

This role is hybrid and based in Boston.

How You’ll Make an Impact

• Enable AI / ML teams across Klaviyo to ship new models and ML-powered features faster, more safely, and more reliably.
• Evolve our ML and LLM platform architecture so teams can build, evaluate, and operate production ML systems with consistent patterns and best practices.
• Improve reliability, observability, and cost efficiency of ML training, inference, and other ML workloads that serve features like smart send time, audience optimization and product recommendations.
• Raise the bar on engineering and operational excellence for systems that support 167K+ customers and billions of events.
• Build and grow a high-performing, inclusive engineering team that operates with ownership, curiosity, and strong customer focus.

What You’ll Do

• Lead, coach, and grow a team of software / ML platform engineers (typically 6–10+ direct reports).
• Set clear goals, provide regular feedback, and support career development aligned with Klaviyo’s Engineering Career Architecture.
• Stay hands-on with the technology: participate in design reviews, code reviews, and occasionally ship code for critical paths or prototypes.
• Partner with product and technical leaders to define and evolve the ML Platform strategy and roadmap, balancing short-term delivery with long-term platform investments.

Learn more about the team’s work in our blogs on Ray Jobs & Ray Tune.

Who You Are

We encourage candidates to apply even if they do not meet all the qualifications listed. ML Platform and MLOps are rapidly evolving spaces and we are all constantly learning.

• 7+ years of experience as a software engineer, ML platform engineer, or similar, building backend or distributed systems.
• 2+ years of experience in a formal people leadership role
• Demonstrated experience launching and operating AI/ML systems in production at scale
• Strong proficiency in Python (or a similar backend language such as Go, Java, or Scala).
• Experience with cloud infrastructure and platform fundamentals (AWS, kubernetes):
• Familiarity with data-intensive systems: streaming or batch processing, data modeling, and designing systems with large-scale data in mind (spark, ray-data).
• Comfortable collaborating with cross-functional technical partners (ML, product, infra, security).
• Strong communication skills and a track record of driving clarity and alignment across teams.

Why You Should Join the Onboarding Team 

The [Product Expansion / Activation] team at Klaviyo is focused on improving the early experience of Klaviyo for new customers. We work diligently to improve the rate at which customers are successfully setting up their Klaviyo account and gaining value from the platform. Engineers on the team use data to discover opportunities for improvement, implement A/B tests to validate ideas, and work across the product to iteratively improve UX and reduce friction for new customers. We are looking for great generalist software engineers with a passion for the experience-layer that have an interest in or experience with growing a user-base and building a great customer onboarding pipeline and experience.

How You Will Make a Difference 

• In this role, you will drive the technical design and lead the implementation of high-impact user-experience improvements across the Klaviyo product, focusing on areas critical to new customer success and adoption. You will own the entire project lifecycle, working through ambiguity and requirements refinement to execution and delivery.
• You will own the end-to-end experimentation process, including contributing to the definition of strategy, architecting and implementing A/B tests to validate product hypotheses, and interpreting data to drive significant iterative improvements. You will be accountable for the quality and operational health of the features you deliver.
• You will serve as a technical leader and liaison, collaborating proactively with partners across teams to define and prioritize key technical initiatives to shape the long-term product roadmap.
• You will take a lead role in mentoring and providing technical guidance to other engineers on the team, elevating our experimentation, development, and operational practices, ensuring contributions consistently leave the product area better than when you found it.
• You will define the architectural approach and technical strategy for your area of responsibility, anticipating scalability and reliability needs, including leveraging AI agents in our work and delivery, ensuring the solution is robust, scalable, and adheres to best practices for security, performance, and maintainability.
• Working from our Boston HQ at least three days a week.

Who You Are 

• Have an extensive background in full stack software engineering, demonstrating deep understanding of Klaviyo’s systems and the ability to architect, deliver, and maintain software with an emphasis on high-scale, user-facing features, and their supporting APIs and infrastructure.
• Demonstrated ability to drive technical strategy and improvement using a data-driven mindset, leading to measurable business results and upholding best practices.
• Demonstrated technical experience in using and championing AI-driven software delivery practices and methods, a passion for continuous learning and mentoring, and the ability to work productively through others to set them up for project success.
• Experience driving A/B testing strategies for products with metric-based goals to significantly improve user experience, customer acquisition, and success is a strong plus.
• Thrives in an entrepreneurial type environment that is customer focused and strategic, while bringing clarity and technical stability to ambiguous challenges and prioritizing work that enables the team to move faster.

Technologies we use (not exhaustive):

• HTML, TypeScript, JavaScript, React
• Python, Django
• MySQL, Cassandra, RabbitMQ, Redis
• Amazon Web Services (EC2, RDS, Aurora, etc.), Terraform, Ansible, Packer, and other DevOps 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

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

About the team

When you hear billing, chances are you might think of a dusty corner office with several decade old file cabinets. Klaviyo’s Billing & Monetization team is not that! We oversee the payments and enforcement infrastructure that allow hundreds of thousands of companies to send billions of emails and text messages on BFCM weekend. The team is responsible for tracking all product usage to bill customers, managing customer subscriptions and payments, and pricing for new and existing products. As Klaviyo continues to scale, our team will play an instrumental role in capturing revenue (both domestic and international), building features that help users understand where their dollar spend goes, complying with regulatory requirements, facilitating internationalization and assisting in all pricing related changes at Klaviyo.

About the role

The Billing & Monetization team is seeking a Software Engineer II to help drive Klaviyo forward in its mission to offer entrepreneurs the best possible tooling at the lowest possible price. You will drive outcomes and decisions directly related to Klaviyo’s growth in international markets, its relationship with large customers with multiple subsidiaries and unique payment requests, how new products are priced and packaged and more.

How you’ll make an impact

• Own customer facing products that help customers better understand how they are billed on Klaviyo. 
• Develop new approaches to track billions of product usage events accurately and reliably.
• Work with Klaviyo customers and stakeholders to build a platform that maximizes value for our customers and for Klaviyo. 
• Make decisions and own outcomes around infrastructure, application logic, documentation, product changes, UI and more

What we’re looking for:

• You have a track record of building high quality products and systems. You take pride in writing clean, high quality code. 
• 3+ years of experience as a software engineer
• Previous experience RESTful APIs, pub/sub systems, and 3rd party integrations 
• You have some experience developing full stack products. 
• Experience working on team projects and/or leading projects.
• You’re excited to use AI-assisted development tools thoughtfully to move faster, improve code quality, and accelerate learning, while applying strong engineering judgment. 

Nice to have:

• Experience building payment systems and or integrating with payment providers.
• Experience working with cross functional teams on bringing products to market, financial reconciliation, etc 
• Passion for understanding and experimenting with the levers that drive business outcomes, including pricing, presentation, vendor relationships and more.
• Experience talking to customers and listening deeply to their wants and needs.

Technologies we use (no experience necessary)

We currently use the list of technologies below but are always looking to find the best tools for the jobs that help our customers (and very open to adding technologies given the right circumstances). We don’t expect you to have any experience in the tools below and we will provide whatever training you need to level up and succeed!

Our current tech stack:

• Python, Django, React, Typescript
• Pulsar, Celery
• MySQL, Redis, Memcached
• AWS (EC2, RDS, S3, etc.), Terraform

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

About the Role

Klaviyo is looking for a Backend Engineer to support key initiatives that enhance our product offerings and drive company growth. In this role, you'll play a critical part in delivering end-to-end solutions using cutting-edge distributed systems and AI technologies. You’ll improve existing products and develop new capabilities that push the boundaries of what’s possible for our customers.

As a Software Engineer II, you’ll tackle complex challenges, explore multiple solutions, and weigh business and technical trade-offs to determine the best path forward. You’ll actively contribute to team discussions and help shape important technology decisions. You'll also be responsible for shipping well-designed, thoroughly tested solutions that prioritize reliability and performance.

The Channel Rendering & Engagement team builds and runs the core infrastructure that turns Klaviyo’s templates and data into the actual messages customers receive - across email, SMS, push, and previews - at massive scale and low latency. We own the high‑performance rendering pipeline, engagement tracking, and compliance-related services. These services collectively ensure that messages are delivered quickly, reliably, and safely. We are the team that guarantees every personalized message is rendered correctly, tracked accurately, and meets strict SLOs, so the rest of Klaviyo can innovate on top of a rock-solid communications platform.

We work cross-functionally by default. Partnering closely with teams across the org gives us broad exposure to the product, lets us unblock other teams, and allows us to drive impact well beyond our immediate scope. The work is fast-moving, varied, and forces us to constantly learn and adapt.

What We’re Looking For

• Experience with distributed systems
• A proven track record of building high-quality products and systems, with a focus on writing clean, maintainable code
• 3+ years of experience in a software engineering role
• Experience building end-to-end software solutions
• Familiarity with various AI tools that enhance the software development lifecycle
• Familiarity with code reviews and leading or participating in robust testing practices
• Experience working in agile, fast-paced environments

Nice to Have

• Python
• Golang
• AWS / knowledge of building cloud-native solutions

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

About the Role

Klaviyo is looking for a Software Engineer II to join the Flows Platform team. In this role, you will help build and operate the core engine that powers all automated lifecycle programs at Klaviyo. You’ll play a critical part in delivering robust, high-scale backend solutions that process billions of events, send millions of messages, and ensure our customers’ automations run reliably and without delay.

As a Software Engineer II, you’ll tackle complex challenges, explore multiple solutions, and weigh business and technical trade-offs to determine the best path forward. You’ll actively contribute to team discussions and help shape important technology decisions. You'll also be responsible for shipping well-designed, thoroughly tested solutions that prioritize reliability and performance.

On the Flows Platform team, we focus on the core of Klaviyo’s automation engine, ensuring that hundreds of millions of actions per day are processed accurately and efficiently to power user workflows. Our work revolves around the core backend systems that determine who receives a message and when, handling complex logic for triggering, filtering, and scheduling at massive scale. We also manage the data stores and infrastructure that support these operations, ensuring reliability while we actively re-architect our stack to support the next generation of event-driven features.

We are responsible for:

• Core Execution Engine: The logic for flow triggering, evaluation (filtering/branching), and action execution. We ensure that every event is processed accurately and efficiently.
• Scheduling & Orchestration: Managing time-based logic, delays, and the dispatching of millions of scheduled actions per day.
• High-Scale Infrastructure: Owning the execution data stores and pipelines that must run reliably at huge scale.

Collaboration is key to what we do. We actively partner with engineering teams across the organization, giving us exposure to diverse parts of the product and opportunities to impact various projects. This keeps us engaged with a variety of challenges and solutions, as we’re always learning and evolving.

What We’re Looking For

• 3+ years of experience in a software engineering role with a focus on backend systems and high-volume data processing.
• Strong Backend proficiency: Deep experience building robust services and APIs using Python and Django (or similar frameworks).
• Distributed Systems knowledge and experience working with asynchronous task queues (e.g. Celery, RabbitMQ, Pulsar) and understanding the challenges of eventual consistency and distributed state.
• Proficiency with relational databases (MySQL/Aurora) and high-scale NoSQL stores (Redis, or DynamoDB).
• A focus on writing clean, maintainable code, participating in code reviews, and leading robust testing practices (unit, integration, and load testing).
• Experience working in fast-paced environments and collaborating with other engineering teams to solve cross-functional problems.
• Experience using AI coding tools like Claude Code or Cursor to accelerate development.

Nice to Have

• Experience with Event-Driven Architecture and streaming technologies like Pulsar or Kafka.
• Experience with Infrastructure as Code (Terraform) and container orchestration (Kubernetes).
• Experience creating technical designs for complex features or system migrations.
• Background in building platforms that support other engineering teams.
• Experience building cloud-native solutions, ideally on AWS

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

Team overview

The Core Infrastructure – Identity & Organizations (Core IO) pillar owns the foundational substrate for identity, access, organizations, and platform integrity at Klaviyo. We manage the critical path of the user journey from login, to enforcing permissions, to operating within the correct organization and regional context so that the rest of the platform can move fast and stay secure.

Within Core IO, the Identity & Access Management (IAM) team builds and operates Klaviyo’s centralized authentication and authorization platform for both humans and machines. We power login, SSO, MFA, SCIM, internal service auth, and external API auth, and we are in the middle of transforming Klaviyo’s identity stack into a unified, enterprise-grade platform.

Why this role is exciting

• Shape Klaviyo’s identity platform: You’ll help design and build the services that every product team and customer relies on login, sessions, permissions, and secure service APIs are all on your roadmap.
• High-leverage, platform-level impact: Your work will directly affect engineering velocity (auth as a shared service), Enterprise deal wins (SSO/SCIM/RBAC/ReBAC), and Data Residency (region-aware auth flows).
• Deep systems and security learning: You’ll work on distributed systems, modern IdP integration, machine auth, and secure-by-default patterns with strong mentorship and meaningful ownership.

What you’ll do

As a Software Engineer II on the IAM team, you will:

• Own features end-to-end across design, implementation, rollout, and observability for core authN/Z capabilities such as login flows, MFA, SSO enhancements, SCIM, sessions, and role/permission enforcement.
• Contribute to auth platform extraction: Help move authentication and authorization paths out of the legacy monolith into dedicated micro services, including token verification, API key services, and internal service auth behind Kong and IdP platform.
• Build and maintain shared SDKs and contracts that let internal teams adopt IAM services quickly (OAuth, machine auth, org-scoped authZ), making “secure by default” the simplest option for new surfaces and agents.
• Collaborate with Organizations & Accounts to support org-scoped identity, multi-account SSO, and flexible org/account models that underpin enterprise experiences and cross-account analytics.
• Partner with Platform Integrity & Protection (PAA), Security, and Compliance on secure patterns for account protection (MFA, recovery, device/session risk), ensuring IAM is a strong foundation for account security and anti-abuse controls.
• Improve reliability and performance of IAM services by instrumenting metrics and alerts, debugging production issues, and contributing to on-call rotations and incident reviews.
• Help define and refine standards for authentication and authorization across the platform APIs, error semantics, audit logging, and integration patterns so product teams don’t reinvent them per-service.

Who you are

You are a mid-level software engineer who has shipped and supported production systems, and who wants to specialize in identity, security, and platform infrastructure.

• Experienced systems builder: You have 2-5+ years of professional software engineering experience, including building and operating backend or full-stack services in production.
• Strong fundamentals & debugging skills: You are comfortable reasoning about data models, API design, concurrency, and failure modes, and you can dig through logs, metrics, and traces to identify root causes and implement systemic fixes.
• Security & identity motivated: You’re excited by authentication, authorization, and account security problems and want to deepen your expertise in areas like MFA, SSO, SCIM, OAuth, and roles/permissions.
• Platform/infra mindset: You like building reusable services and tools that other engineers rely on, including libraries, SDKs, and patterns that raise the floor for quality and security across the org.
• Ownership & collaboration: You take responsibility for outcomes, not just code. You’re comfortable driving a small project or component, coordinating with partner teams, and communicating trade-offs clearly in design docs and PRs.
• 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.

Minimum qualifications

• 2-5+ years of professional software engineering experience.
• Proficiency in at least one of Python, Go, or TypeScript/JavaScript, and comfort working on backend and/or service-oriented systems.
• Experience building or operating web services or APIs backed by relational databases and/or caches (e.g., MySQL, Postgres, Redis).
• Familiarity with authentication or authorization concepts (sessions, tokens, OAuth, SSO, MFA, RBAC) and an interest in going much deeper.
• Exposure to CI/CD pipelines and modern development workflows (code review, testing, deployments, on-call participation or support).

Nice to have

You don’t need all of these, but experience in any of the following is a bonus:

• Building or integrating with IdPs and identity protocols (SAML/OIDC, enterprise SSO, SCIM, OAuth, API key management).
• Working with cloud-native infrastructure (AWS, Kubernetes, Terraform, Kong, or similar API gateways and service meshes).
• Experience with high-scale distributed systems or performance-sensitive services where availability and latency targets matter (e.g., auth endpoints, org lookups, internal service auth).
• Familiarity with observability stacks (Grafana, Datadog/Splunk, internal metrics/logging frameworks) and using them to drive reliability improvements.
• Interest or experience in adjacent Core IO domains like Organizations & Accounts or Platform Anti-Abuse (PAA), especially where they intersect with auth and account security.

Technologies we use (not exhaustive)

You’ll work with some of these on day one and have opportunities to learn the rest:

• Languages & frameworks: Python, Django, Go, TypeScript/React.
• Identity & access: OAuth, API keys, SSO, SCIM, MFA, roles & permissions, internal service auth SDKs.
• Infrastructure & platform: AWS, Kubernetes, Terraform, Kong, microservice platform for auth and organizations.

Data & observability: MySQL, Redis, Kafka/queues, Grafana, Splunk, internal logging/metrics pipelines.

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

About the Role

Klaviyo is looking for a Full Stack Engineer to join the Social team and help turn social conversations into long‑term customer relationships. In this role, you'll build end‑to‑end experiences that connect channels like Instagram DMs to Klaviyo’s core platform—capturing high‑intent profiles, consent, and engagement data from social traffic.

As a Software Engineer II, you’ll tackle complex technical challenges, explore multiple solution paths, and weigh business and technical trade‑offs to determine the best approach. You’ll contribute actively to design discussions, help shape architectural decisions, and ship well‑designed, thoroughly tested features that prioritize reliability, performance, and a great user experience.

On the Social team, we focus on crafting intuitive, high‑impact surfaces that make it easy for brands to grow their lists from social. This includes the experiences that power Instagram auto‑replies and future social entry points, the supporting APIs and services that ingest and transform social events, and the data and analytics that show customers how social programs drive profile growth and revenue. We partner closely with teams across messaging channels, onsite experiences, and profiles to create a cohesive, multi‑channel growth engine.

Collaboration is central to how we work. You’ll work with engineers, product managers, designers, and data partners across Klaviyo, gaining exposure to many parts of the stack and product. This keeps the work varied and gives you opportunities to see your code in action across different surfaces—from customer storefronts to internal analytics tools.

Looking ahead, Social is expanding beyond our first Instagram auto‑reply experiences into a broader social growth platform. We’ll be deepening our native social integrations, building smarter targeting and personalization based on profile and event data, and creating new ways to route social traffic into high‑conversion destinations like landing pages and onsite modules. Our goal is to make Social not just a feature, but a growth platform that helps brands turn every conversation into a durable customer relationship.

What We’re Looking For

• A proven track record of building high-quality products and systems, with a focus on writing clean, maintainable code
• 3+ years of experience in a software engineering role
• Experience building end-to-end software solutions or deep experience with both front-end and back-end technologies
• Familiarity with code reviews and leading or participating in robust testing practices
• Experience working in agile, fast-paced environments

Nice to Have

• Experience with Python and related technologies
• Experience with React and related technologies
• Background in digital marketing or customer data software
• Exposure to machine learning concepts or applications
• Experience building cloud-native solutions, ideally on AWS

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

About the Role

Klaviyo is looking for a Full Stack Engineer to support key initiatives that enhance our product offerings and drive company growth. In this role, you'll play a critical part in delivering end-to-end solutions using both front-end and back-end technologies. You’ll improve existing products and develop new capabilities that push the boundaries of what’s possible for our customers.

As a Software Engineer II, you’ll tackle complex challenges, explore multiple solutions, and weigh business and technical trade-offs to determine the best path forward. You’ll actively contribute to team discussions and help shape important technology decisions. You'll also be responsible for shipping well-designed, thoroughly tested solutions that prioritize reliability and performance.

The WhatsApp team builds the end-to-end experience for Klaviyo’s WhatsApp channel, making it easy and powerful for customers to use our newest messaging channel effectively. We own the core WhatsApp product surface across Klaviyo, ensuring it’s available wherever customers expect it, while building and operating WhatsApp-specific capabilities like outbound and inbound pipelines and Meta template management.

We work cross-functionally by default. Partnering closely with teams across the org gives us broad exposure to the product, lets us unblock other teams, and allows us to drive impact well beyond our immediate scope. The work is fast-moving, varied, and forces us to constantly learn and adapt.

Looking ahead, our focus is on scaling WhatsApp across Klaviyo. That means closing feature gaps, rapidly integrating new Meta capabilities, and running targeted adoption experiments to drive usage. The goal is simple: deliver the most complete, high-quality WhatsApp integration in the market—and set the bar for what a marketing platform can do with this channel

What We’re Looking For

• A proven track record of building high-quality products and systems, with a focus on writing clean, maintainable code
• 3+ years of experience in a software engineering role
• Experience building end-to-end software solutions or deep experience with both front-end and back-end technologies
• Familiarity with code reviews and leading or participating in robust testing practices
• Experience working in agile, fast-paced environments

Nice to Have

• Experience with Python and related technologies
• Experience with React and related technologies
• Background in digital marketing or customer data software
• Exposure to machine learning concepts or applications
• Experience building cloud-native solutions, ideally on AWS

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

Why You Should Join the Onboarding Team 

The [Product Expansion / Activation] team at Klaviyo is focused on improving the early experience of Klaviyo for new customers. We work diligently to improve the rate at which customers are successfully setting up their Klaviyo account and gaining value from the platform. Engineers on the team use data to discover opportunities for improvement, implement A/B tests to validate ideas, and work across the product to iteratively improve UX and reduce friction for new customers. We are looking for great generalist software engineers with a passion for the experience-layer that have an interest in or experience with growing a user-base and building a great customer onboarding pipeline and experience.

How You Will Make a Difference 

• In this role, you will implement user-experience improvements across the Klaviyo product, especially in areas that affect new customers.
• You will design and implement A/B tests to validate ideas, and interpret the results of these tests to inform iterative improvements to the product.
• You will collaborate with marketing, data-science, sales, and engineering teams to discover areas for improvement, as well as engaging with customers directly to learn more about how we can better serve their needs.
• You will help us improve our experimentation and development processes, and mentor other engineers on the team.
• You will clearly define the goal, constraints, and context for AI agents, while remaining responsible for the correctness of the implementation, with a focus on security, performance, and maintainability.
• Working from our Boston HQ at least three days a week.

Who You Are 

• Have a background in full stack software engineering with experience building and improving products with an emphasis on user-facing features, along with the APIs and infrastructure to support them.
• Passionate about growing and improving a product on a daily basis using a data driven mindset.
• Experienced with A/B Testing products with metric based goals to improve user experience and customer acquisition and success (nice to have)
• Demonstrated ability and success in using AI-driven software delivery practices and methods and/or a willingness and excitement to learn.
• Thrives in an entrepreneurial type environment that is fast paced, customer focused, and strategic.

Technologies we use (not exhaustive):

• HTML, TypeScript, JavaScript, React
• Python, Django
• MySQL, Cassandra, RabbitMQ, Redis
• Amazon Web Services (EC2, RDS, Aurora, etc.), Terraform, Ansible, Packer, and other DevOps 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

About the Role

Klaviyo is looking for a Full Stack Engineer to support key initiatives that enhance our product offerings and drive company growth. In this role, you'll play a critical part in delivering end-to-end solutions using both front-end and back-end technologies. You’ll improve existing products and develop new capabilities that push the boundaries of what’s possible for our customers.

As a Software Engineer II, you’ll tackle complex challenges, explore multiple solutions, and weigh business and technical trade-offs to determine the best path forward. You’ll actively contribute to team discussions and help shape important technology decisions. You'll also be responsible for shipping well-designed, thoroughly tested solutions that prioritize reliability and performance.

On the Flows Insight & Management team, we focus on crafting an exceptional user experience for the Flows product area which empowers users to build, manage, and analyze automated workflows seamlessly. Our work revolves around an intuitive visual editor that lets users create and modify flows with ease, as well as the rich insights and analytics that help them understand how their flows are performing. We also manage APIs that integrate with other services, creating a powerful ecosystem for users to drive automation in new and exciting ways.

Collaboration is key to what we do. We actively partner with engineering teams across the organization, giving us exposure to diverse parts of the product and opportunities to impact various projects. This keeps us engaged with a variety of challenges and solutions, as we’re always learning and evolving.

Looking to the future, our team is focused on expanding the capabilities of Flows. We’ll be enhancing our flow editor and ecosystem to make it even easier to build and expand on flows. We’re also building smarter recommendations and actionable insights to help users optimize their flows. With our continued evolution, we envision Flows not just as a tool, but as a platform that empowers teams to do more, build more, and connect seamlessly.

About the Team

^{The Flows Insight & Management team owns how customers design, understand, and manage automated lifecycle programs across channels like Email, SMS, and WhatsApp. We are responsible for:}

• ^{The Flows User Experience: Building an intuitive visual editor, staff-side management tools, and the analytics previews that allow users to create and modify flows with ease.}

• ^{Developer APIs: Managing the configuration and APIs that handle creating, editing, cloning, and versioning flows.}

• ^{Analytics & Reporting: Delivering rich insights, node-level metrics, and revenue/conversion analytics that help users understand exactly how their automations are performing.}

• ^{Looking to the future, we are focused on expanding the flow editor ecosystem and building smarter recommendations and actionable insights to help users optimize their strategies.}

What We’re Looking For

• 3+ years of experience in a software engineering role with a proven track record of building high-quality products.
• Strong Full Stack proficiency: Experience building end-to-end solutions using Python and Django on the backend, and React and TypeScript on the frontend.
• API Design experience: Ability to design and maintain robust RESTful APIs (experience with developer-facing APIs is a plus).
• Infrastructure & Database knowledge: Familiarity with relational databases (MySQL/Aurora) and exposure to cloud infrastructure, specifically AWS.
• Engineering best practices: A focus on writing clean, maintainable code, participating in code reviews, and leading robust testing practices.
• Agile collaboration: Experience working in fast-paced environments and partnering effectively with Product and Design teams.
• Experience using AI coding tools like Claude Code or Cursor to accelerate development.

Nice to Have

• Experience with infrastructure as code, such as Terraform.
• Familiarity with asynchronous task queues and event-driven architecture (Pulsar, Kafka, RabbitMQ, Celery).
• Background in digital marketing, customer data software, or building analytics products.
• Exposure to machine learning concepts, as we work towards building smarter recommendations for our users.
• Experience building cloud-native solutions, ideally on AWS.

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

Team Overview:

The Amplify Engineering team builds internal tools, platforms, and AI-powered automation that help Klaviyos work more efficiently and at scale as the company grows. We partner across the organisation, including Sales, Marketing, Engineering & Product, Customer Service & Success, and Finance, to solve real operational problems with practical, well-designed software.

Our work spans internal applications, 3rd-party integrations, interactive dashboards, CMS integrations, and robust AI systems and agents that automate repetitive tasks, surface the right information at the right time, and help teams make better decisions. We operate in tight feedback loops with our internal customers, shipping quickly, learning fast, and seeing the impact of our work immediately in how deals move faster, tickets resolve sooner, and launches go more smoothly.

This role is for builders and leaders who enjoy turning real-world pain points into reliable, scalable solutions. The work is highly visible and deeply impactful, shaping how thousands of Klaviyos get their work done every day through fast iteration, high ownership, and clear outcomes.

How You’ll Make an Impact:

The Amplify team builds the internal platforms, automation, and AI-driven systems that power how Klaviyos work every day. As an Engineering Manager, you will:

• Lead one or more engineering teams and help shape the technical direction for internal tools and platforms that improve efficiency, automation, and productivity.
• Lead a portfolio of internal systems supporting Sales, Marketing, Customer Service & Success, R&D, and Finance, including AI-powered workflows, internal web applications, data and event pipelines, third-party integrations, and support tooling.
• Balance technical leadership and people leadership, setting direction, modelling best practices, and enabling teams to deliver effectively through others.
• Partner closely with engineers, product managers, designers, and senior stakeholders to translate organisational challenges into scalable, high-quality software solutions.
• Learn and evolve Klaviyo’s end-to-end internal workflows, scaling platforms and processes to support the company’s next phase of growth.
• Foster a culture of collaboration, systems thinking, technical excellence, and curiosity around new technologies, including AI.
• Make a direct and visible impact on how thousands of Klaviyos get their work done every day.

Who You Are:

• You are passionate about building software for the long term, balancing technical quality, delivery pace, and business impact.
• BA or BS Degree in Computer Science, related field, or equivalent experience.
• You have 5+ years of hands-on software development experience building and operating highly available, full-stack SaaS products, with a solid understanding of modern web architectures and scalable, multi-tenant systems.
• You have 3+ years of experience as an engineering manager, leading high-performing teams that deliver complex, cross-team initiatives using an agile, iterative approach.
• You are a technically curious leader with hands-on experience using modern AI tools and workflows (e.g. OpenAI, Anthropic, Gemini, n8n) and an interest in helping teams apply them thoughtfully to improve productivity and outcomes.
• You are comfortable setting technical direction and standards, working with peers and senior leadership to evolve architecture, development practices, and shared engineering processes.
• You have experience owning work end-to-end – from design through delivery and deployment, including planning, estimation, and managing delivery risks.
• You are an effective cross-functional communicator, able to work closely with product, design, and business partners to align priorities and move work forward.
• You are a people-first leader who enjoys hiring, onboarding, mentoring, and developing engineers, creating an environment where individuals and teams can grow and do their best work.
• You enjoy leading teams that build internal platforms, tools, or systems that improve productivity, automation, and operational efficiency across an organisation.
• You like to question convention, continuously improve how work gets done, and thrive in small, autonomous teams that ship early and often in close partnership with their stakeholders.

Nice to have:

• Experience building internal tools, platforms, or automation for developers and/or non-technical teams.
• Hands-on experience in full-stack environments, including diagnosing and improving application performance.
• Strong practical experience using AI tools and patterns (e.g. APIs/SDKs, prompt and context design, automated or agentic workflows, RAG, and evaluation or monitoring).
• Experience working with cloud infrastructure (AWS preferred), including infrastructure-as-code and containerised environments (Terraform and Kubernetes). Familiarity with GCP or Azure is a plus.

30 / 60 / 90 / 6-12 Month Plan:

30 Days: Build context across the Amplify domain by learning the teams’ areas of ownership, architecture, and core workflows. Establish trust with engineers and partners while contributing to technical discussions and trade-off decisions.

60 Days: Assess team roadmaps and delivery practices, incorporating input from engineers and stakeholders. Align priorities with the technical direction and business goals you are helping to shape, and begin contributing to hiring and team growth.

90 Days: Improve how teams and stakeholders work by introducing or refining tools, processes, or architectural approaches. Provide technical leadership through reviews, guidance, and targeted hands-on contributions where helpful.

6-12 months: Be a trusted owner of your teams’ platforms and systems, known for delivering meaningful, scalable impact. Partner closely with product and design to drive adoption of Amplify systems and evolve them to support Klaviyo’s continued growth.

Technologies We Use:

Klaviyo’s platform is primarily built with Python and React and runs on AWS. New hires join us from a wide range of technical backgrounds and are supported in learning our stack. Core technologies include:

• Python / Django / FastAPI
• Typescript / React
• MySQL / Redis / Memcached
• RabbitMQ / Celery / Apache Kafka / Apache Pulsar
• AWS / Terraform / Kubernetes

Location & Work Model

This role is based in Dublin, Ireland, and follows a hybrid working model. Klaviyo supports work authorization and relocation for this position.

At Klaviyo, we enjoy tackling meaningful engineering challenges and value people who take ownership, learn continuously, and collaborate openly. We are committed to building inclusive teams and encourage applications from candidates of all backgrounds.

Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech

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

#indeedDUB

Location: Boston Hybrid (3 days/week in office)

Why You Should Join the Team

The Klaviyo Conversational AI Platform team is building the foundation for how Klaviyo customers plan, create, edit, and iterate on their marketing strategy through an in‑app, AI‑powered conversational experience. We own the native chat surface, the agent orchestrator, and the agentic UI framework that other teams across Klaviyo will plug into.

 By joining the Klaviyo Conversational AI Platform team, you will have the opportunity to have a direct impact on over 170,000 brands that use Klaviyo every day to engage with their customers. You’ll also help define and build Klaviyo’s Autonomous Marketing platform: an ecosystem of LLM‑powered agents that can analyze, create, and optimize marketing programs across campaigns, flows, forms, and more.

As the Engineering Manager for Klaviyo Conversational AI Platform, you will lead a fullstack team that owns the main Conversational AI Platform UI while designing the core intent-routing orchestrator and shared agent platform that other teams use to plug in.

This role requires excellent communication and collaboration skills. You will work closely with product managers, product designers, and many other engineering teams to extend and drive evolution of the product.

How You Will Make a Difference

• Lead a team of engineers delivering fullstack, customer-facing features used across Klaviyo’s Conversational AI Platform product offering
• Set the technical direction for the orchestrator that handles intent detection, routing, planning, and multi‑step LLM workflows across many expert agents.
• Own end-to-end execution: scope initiatives, break down work, align dependencies, and deliver high-quality releases on predictable timelines
• Drive architectural decisions that prioritize scalability, reliability, and maintainability across services, data models, and shared component systems
• Partner closely with Product and Design to translate vision into intuitive, performant user experiences
• Drive cross-team collaboration with Engineering to ensure the smooth integration of AI agents across teams.
• Grow and mentor engineers, fostering a high-performance and inclusive team culture
• Collaborate across Klaviyo to align roadmaps and ship cohesive, customer-delighting solutions
• Contribute hands-on via design docs, code reviews, and technical spikes to de-risk complex bets and model engineering excellence

Who You Are

• 8+ years of software engineering experience with strong frontend and backend skills
• 5+ years of engineering management experience, ideally managing fullstack teams.
• Familiarity with frontend technologies like React, TypeScript, and state management tools such as Redux
• Comfortable contributing to backend systems using Python and Django, FastAPI (or equivalent)
• Skilled in system design, reusable component architecture, and scalable frontend platforms
• Familiarity DevOps tooling, cloud infrastructure (AWS), Terraform, etc.
• Proven track record delivering complex features in fast-paced, product-led environments
• Clear communicator, collaborative leader, and committed to continuous team improvement
• Experience designing or leading systems that use LLMs, tools, or agent‑like workflows

Technologies We Use

• React, TypeScript, Redux
• Python, Django, FastAPI, Langchain
• MySQL, Redis, RabbitMQ, Pulsar, 
• GraphQL, RESTful APIs
• AWS, Terraform, Kubernetes

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

Why You Should Join the PLS (Profiles, Lists and Segments) Team:

The PLS team is responsible for building and scaling the core customer data experiences at Klaviyo — profiles, lists, and real-time segments. We own the tools that let customers understand who their users are, group them into meaningful audiences, and keep those audiences up to date as new data flows in. Our work underpins how customers target, personalize, and measure every message they send, making this product area core to Klaviyo’s continued success.

As a Senior Software Engineer on the team, you’ll play a key role in designing and building scalable systems that power how customers manage and activate their data. Partnering closely with product managers, data scientists, and other platform teams, you’ll help define scope, translate complex data and UX problems into practical implementations, and build intuitive workflows that give customers confidence in their audiences. This role leans frontend, with a strong focus on crafting thoughtful, reusable components and seamless user experiences using technologies like TypeScript, React, Python, and Django. There are ample opportunities for growth given the scope of this role and the team’s central role in Klaviyo’s product.

How You Will Make a Difference:

• You will be a core member of the PLS team, working on impactful customer-facing features that will make our product the best in the industry.
• You will work on creating easy-to-use editors that are highly performant.
• You will work closely with Product, Design, and Data Science to provide the best experience for our customers.
• You will mentor team members and drive initiatives that help the team learn new skills.

Who You Are:

• 5+ years of experience in full-stack development with strong hands-on skills in React, Redux, JavaScript, HTML, and CSS, along with familiarity with general web best practices.
• Has a track record of delivering and shipping work powered by or accelerated through AI.
• Experience conducting code reviews and running a robust testing cycle using automated testing practices and frameworks, including end-to-end and integration tests (e.g., cypress, pytest).
• Experienced with RESTful and GraphQL APIs, and evolving APIs and data models to support product success.
• You take ownership of your work—from requirements and edge cases to implementation and testing—and are motivated by solving tough problems with others.
• Proven track record of leading complex, multi-quarter projects involving cross-team collaboration and being accountable for their outcomes

Technologies We Use (not exhaustive):

• React, TypeScript, Redux
• Python, Django
• Amazon Web Services (EC2, RDS, Aurora, S3, etc.), Terraform, and other DevOps tools
• MySQL, RabbitMQ, Redis, ProxySQL

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

Hybrid 3x/week out of Boston.

At Klaviyo, we empower creators and businesses to own their customer relationships. Our platform processes billions of events and powers real-time personalization, automation, and analytics for thousands of customers. At the core of this platform is our data infrastructure — the systems that ingest, store, transform, and serve customer data at scale.

About the Role

The Profile Traits team owns how customer profile data is represented, stored, mutated, and served across Klaviyo. Profile traits are one of the most critical primitives in the platform: they power segmentation, personalization, flows, analytics, and emerging AI-driven features.

As Engineering Manager, Profile Traits, you will lead a team of engineers responsible for building and scaling these foundational systems. This role sits at the intersection of distributed systems, data modeling, and product semantics, with a strong emphasis on correctness, performance, and long-term platform evolution.

You will partner closely with product managers and adjacent platform teams (Events, Identity & Consent, Segmentation, Flows) to ensure profile data remains reliable, fast, and easy to reason about as Klaviyo continues to grow.

What You’ll Do

• Lead, mentor, and grow a team of engineers building Klaviyo’s profile traits platform
• Own systems responsible for profile attribute storage, mutation, and serving
• Drive technical and execution excellence across correctness, latency, and cost
• Partner with product and platform teams to define roadmaps and priorities
• Guide architectural decisions around schema evolution, consistency, and scale
• Participate in design and code reviews to maintain a high technical bar
• Foster a culture of ownership, collaboration, and continuous improvement

What You’ll Work On

• High-QPS, stateful systems supporting real-time and nearline profile updates
• Schema evolution and backward compatibility for long-lived customer data
• Mechanisms for trait computation, backfills, and data migrations
• Improving debuggability, observability, and operational maturity
• Scaling profile read and write paths to support new product capabilities

Who You AreRequired Qualifications

• 8–10+ years of software engineering experience
• 3+ years of engineering management experience
• Experience owning and evolving stateful or data-intensive systems at scale
• Strong understanding of distributed systems tradeoffs
• Proven ability to coach and develop senior engineers
• Experience partnering with Product on ambiguous, platform-oriented problems

Nice to Have

• Experience with high-QPS OLTP systems
• Background in data consistency, data modeling, or schema evolution
• Experience supporting both online and analytical workloads
• Familiarity with cloud-native systems (AWS preferred)

Why This Role Matters

Profile traits are how customers experience their data in Klaviyo. Small decisions in these systems can have outsized impact — from segmentation accuracy to real-time personalization to AI-driven insights. This role offers the opportunity to shape a core platform capability while leading a team solving complex, high-impact technical problems.

Technologies We Use

Our stack evolves with our needs, but today includes:

• Distributed services built primarily in Python and Go
• Cloud infrastructure on AWS
• Stream processing and data pipelines at scale
• A mix of real-time, nearline, and analytical data systems

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

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 data analytics platform written primarily in Python that is built for massive scale and hosted on Amazon Web Services (AWS). The Data Automation team builds tooling and establishes best practices and technology choices that help enable the Data Platform area to power core Klaviyo functionality and generate data-driven insights.

As a founding member on the Data Automation team, you will have ownership over defining the technical and organizational vision for the team. You will be responsible for leading the team to design and build systems that help us operate our mission critical analytics infrastructure.

Team Tech Stack:

• AWS
• Terraform
• Python
• Kubernetes
• Clickhouse
• DynamoDB
• MySQL
• Kafka
• Spark
• Flink
• Airflow

How You'll Make a Difference

• You will be responsible for building and managing a team of 7+ engineers to fulfill your data automation vision and roadmap.
• Responsible for coaching engineers, managing/reviewing technical documentation and articulating a phased approach to achieving the team's overall technical vision.
• Be responsible for the mission, technical direction and operations of projects that have immediate impact.
• Wholly owning the frameworks that enable us to provision, update, test, monitor, and scale infrastructure to power features that 183,000+ customers rely on daily to reach 4B+ consumers to drive their business forward.
• Optimizing infrastructure with the teams that own Klaviyo’s analytics system that provides insight on hundreds of terabytes of data.
• Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up.

Required Skills

• BA or BS Degree in Computer Science, related field, or equivalent experience
• 8+ years of software engineering experience in a DevOps environment with specific experience in data processing systems.
• 3+ years of people management experience
• Hands-on experience designing, building, and operating reliable, fault-tolerant, and high performance distributed systems
• Ability to handle yourself in outage situations and to drive failures to root cause analysis and prevention of future issues
• Experience writing code using best practices in a language such as Python, Ruby, Go, etc.
• 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.
• Proven ability to come up to speed quickly
• Hybrid office work 3x/week out of our Boston office

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

Senior Software Engineer, AI & Analytics Data Enablement

Location: Boston, MA

As a Senior Software Engineer on Klaviyo’s AI & Analytics Data Enablement team, you’ll build and own the data foundations that power our Analytics & AI engine. You’ll design resilient pipelines and analytics models that turn billions of events and domain objects into trusted, actionable insights for Analytics and AI product features. “Your work will help our customers understand the performance of their marketing and power AI & Analytics experiences for our customers.”

About the Role

You’ll join a cross-functional R&D team focused on the availability, quality, and usability of AI and Analytics data for our customers. In this Senior-level role, you’ll lead complex software and data engineering projects across multi-component systems, from shaping requirements to design, implementation, and long-term operation. You’ll be a go-to expert for AI and analytics data, collaborating with product managers, AI, analytics, and other engineering teams to ensure our data is accurate, observable, and ready to drive insights and enable AI/ML products at scale.

You’ll also help evolve our technical standards for data engineering, raising the bar on data modeling, performance, and reliability, while mentoring other engineers on best practices and modern data tooling.

What You’ll Do

Lead the design and implementation of robust, scalable data pipelines and core tables for Klaviyo. These pipelines are crucial for powering customer facing analytics features and powering AI models to unlock the next stage of Klaviyo's products

Partner with Product, Engineering, and AI/ML teams to define clear, consistent metrics and data contracts that align to business goals and product outcomes.

Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up for example, using AI to generate tests, detect anomalies, summarize data issues, or accelerate analysis.

Mentor other engineers in data engineering best practices, code quality, observability, and system design; contribute to shared libraries, patterns, and tooling that improve developer velocity across R&D.

Who You Are

6+ years of software engineering with at least 4 or those being data engineering experience, with a strong track record building and operating data pipelines and analytics models in production.

Deep proficiency in large-scale SQL and data modeling for analytics. 

Strong programming skills in a modern language commonly used for data engineering (e.g. Python), and familiarity with orchestration and transformation tooling (e.g., Airflow, EMR, Spark/pyspark, or equivalents).

Experience working with modern data platforms (e.g., columnar data warehouses, object storage) and processing frameworks (batch and/or streaming).

Demonstrated ability to lead complex projects spanning multiple components and engineers—driving clarity, making tradeoffs, and delivering measurable impact on reliability, performance, or business outcomes.

Comfortable owning systems in production: you think about observability, incident response, incremental rollouts, and long-term maintainability as part of the design.

Excellent communication skills; you can explain data tradeoffs and constraints to non-technical partners and influence decisions with clear reasoning.

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.

Inclusive, low-ego collaborator who values diverse perspectives and is motivated by helping the team succeed, not just shipping your own code.

Nice to Haves

Experience in a product-led SaaS environment with large-scale event data

Experience in a customer facing data engineering role supports AI/ML features and Analytics Dashboards.

Hands-on work with analytics engineering tools and practices (e.g., dbt, metrics layers, semantic models).

Experience building near real-time or streaming pipelines for user-facing analytics or monitoring.

Domain experience in martech, marketing automation, or customer engagement platforms.

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

About the Role

Our team is looking for a Senior Full Stack Engineer to lead key initiatives that will enhance our product offerings and support our company’s growth. In this role, you'll play a crucial part in shaping outcomes by developing innovative end-to-end solutions using both front-end and back-end technologies. You’ll optimize existing products and create new solutions that redefine what’s possible for our customers.

As a Senior Engineer, you’ll tackle complex challenges, develop multiple solutions, and evaluate business and technical trade-offs to determine the best path forward. You’ll also act as a leader and mentor, and drive key technology decisions. Additionally, you’ll be responsible for deploying well-designed, thoroughly tested solutions that ensure reliability and performance.

The New Products team drives Klaviyo’s most ambitious innovations—creating and scaling the company’s boldest new bets. As a nimble group with a flat structure and fast-moving culture, we prioritize simplicity, speed, and impact. Every team member is expected to take radical ownership—rolling up their sleeves, collaborating across disciplines, and pushing beyond traditional role boundaries to make things happen. Success in this role means delivering exceptional work that sets the standard for velocity and results company-wide, while helping shape Klaviyo’s future through experimentation, creativity, and executional excellence.

What We’re Looking For

• A proven track record of building high-quality products and systems, with pride in writing clean, high-quality code.
• 7+ years of experience in a software engineering role.
• Strong experience developing end-to-end software solutions or extensive experience with both front-end and back-end technologies.
• Experience leading projects and being accountable for their outcomes.
• Experience mentoring team members or driving initiatives that help the team learn new skills.
• Experience conducting code reviews and running a robust testing cycle.
• Experience working in agile, fast-paced environments.
• 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.
• Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up.

Nice to Have

• Skills with Python and related technologies
• Skills with React and related technologies
• Experience developing digital marketing or customer data software solutions.
• Experience with machine learning.
• Experience building cloud-native solutions, ideally with AWS.

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

#indeedRD

Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech

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.

Klaviyo operates a real-time data platform coded in Python built for massive scale on Amazon Web Services (AWS). Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

Team Overview: 

DevX is a hybrid product–platform team focused on empowering external developers and partners by supporting applications they build on top of Klaviyo’s Public APIs and features. Examples of these areas of ownership include:

• our Application directory, which is used to promote and allow Klaviyo customers to discover applications that they can enable for their account
• the self-serve application process for a Partner to submit an Application and the ability for Klaviyo staff to review and approve an Application
• API Analytics is a system used by developers and partners to diagnose issues in their applications and understand their API usage. It is powered by a near real–time data pipeline that processes over 160,000 events per second.
• Autogenerated API docs, SDKs, CLIs & MCP servers

Responsibilities:

You will have an opportunity to make a major impact on the direction and priorities of the team.

As an engineer on this team, you will work on Klaviyo’s app marketplace, application publishing workflows, and the developer-facing tools and systems that support our app ecosystem. Additional responsibilities include providing quality PR reviews for our code-owned areas of the application, collaborating with product owners and providing technical expertise on upcoming Product Specifications, and participating in the definition of well-defined, estimated, and planned scopes of work.

Required Skills: 

• 5+ years of experience in a software engineering discipline
• Experience with full stack application development
• Experience working with both monolithic and microservices architectures
• Experience with CI/CD pipelines
• Experience debugging performance issues and improving application performance

Team Tech Stack:

• Python
• Django REST Framework, Django, fastAPI
• React, React Query
• MySQL / postgreSQL
• DocumentDB
• Clickhouse
• JSON Forms
• Redis
• Memcached
• RabbitMQ / Celery / Apache Pulsar

Preferred Skills:

• Experience working with Service Oriented Architecture (preferably in Python)
• Experience working with RESTful applications/APIs/gRPC

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

Location: Boston Hybrid (3 days/week in office)

Why You Should Join the Flows Insights & Management Team

The Flows Insights & Management team is building the foundation for how Klaviyo customers create, manage, and configure their Klaviyo-powered automations.  This team also owns the reporting experiences that allow our customers to understand the performance and impact of their Flows. By joining the Flows I&M team, you will have the opportunity to have a direct impact on over 170,000 brands that use Klaviyo every day to engage with their customers.

As the Engineering Manager for the Flows Insights & Management team, you will lead a group of fullstack engineers and collaborate with other engineering teams to build and evolve Klaviyo’s Flows product as our customer’s needs evolve.

You will be responsible for guiding execution on major new Flows features, including additional sending channels, intelligent personalizations, technical evolution, and scalability. This role blends technical leadership, architectural direction, and people management. 

As the Engineering Manager of one of our flagship products, this role requires excellent communication and collaboration skills. You will work closely with product managers, product designers, support, and many other engineering teams to extend and drive evolution of the Flows product.

How You Will Make a Difference

• Lead a team of engineers delivering fullstack, customer-facing features used across Klaviyo’s Flows product offering
• Set technical direction for multi-channel Flows (e.g., email, SMS, push), including intelligent personalization and future channel expansion
• Own end-to-end execution: scope initiatives, break down work, align dependencies, and deliver high-quality releases on predictable timelines
• Drive architectural decisions that prioritize scalability, reliability, and maintainability across services, data models, and shared component systems
• Partner closely with Product and Design to translate vision into intuitive, performant user experiences
• Grow and mentor engineers, fostering a high-performance and inclusive team culture
• Collaborate across Klaviyo to align roadmaps and ship cohesive, customer-delighting solutions
• Contribute hands-on via design docs, code reviews, and technical spikes to de-risk complex bets and model engineering excellence

Who You Are

• 8+ years of software engineering experience with strong frontend and backend skills
• 5+ years of engineering management experience, ideally managing fullstack teams.
• Familiarity with frontend technologies like React, TypeScript, and state management tools such as Redux
• Comfortable contributing to backend systems using Python and Django, FastAPI (or equivalent)
• Skilled in system design, reusable component architecture, and scalable frontend platforms
• Familiarity with DevOps tooling, cloud infrastructure (AWS), Terraform, etc.
• Proven track record delivering complex features in fast-paced, product-led environments
• Clear communicator, collaborative leader, and committed to continuous team improvement
• 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

• React, TypeScript, Redux
• Python, Django, FastAPI
• MySQL, Redis, RabbitMQ, Pulsar, 
• GraphQL, RESTful APIs
• AWS, Terraform, Kubernetes

#IndeedRD

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

Team Overview:

The mission of the Asynchronous Processing team is to design, build, and operate Klaviyo’s high-scale, event-driven backbone so that every product team can reliably move data through our systems with confidence, no matter the volume. By providing opinionated, self-service platforms for queueing and background processing–grounded in technologies like Golang, Python, Apache Pulsar, Kafka, SQS, AWS, and Kubernetes–we enable engineering teams to focus on customer impact while we ensure their workloads are fast, observable, cost-efficient, and resilient by default.

As a Senior Platform Engineer on the Asynchronous Processing team, you will architect, build, and operate the large-scale, event-driven backbone that powers Klaviyo, crafting paved-path primitives on top of Golang, Python, Apache Pulsar, Kafka, and SQS running in AWS and Kubernetes. You’ll design and evolve resilient, multi-tenant queueing and processing platforms that safely handle massive spikes in traffic, process millions of messages per second with low latency, and provide simple, self-service APIs and tooling that enable product teams to move fast and with confidence. From core data models and routing patterns to observability, autoscaling, and failure isolation, you’ll own systems that must be rock solid at scale, partnering closely with engineers across the company to turn complex distributed-systems problems into intuitive, reliable building blocks.

This role is for senior engineers who love taming large-scale distributed systems and turning real-world asynchronous workloads into reliable, scalable platforms. You’ll work on highly visible infrastructure at the heart of Klaviyo’s event-driven backbone, directly shaping how thousands of Klaviyos build, ship, and operate products every day.

How You’ll Make an Impact:

The Asynchronous Processing team builds and operates Klaviyo’s high-scale, event-driven backbone that powers reliable, low-latency async workloads for every product team. As a Senior Platform Engineer on the Asynchronous Processing team, you will:

• Build a deep understanding of engineering needs across the organization, guiding the design and development of appropriate platform primitives in queueing that align with the platform's vision and practically empower product teams.
• Design, develop, and deliver software to dramatically improve the availability, scalability, latency, and efficiency of Klaviyo's asynchronous and queueing services.
• Design and develop systems and processes that enable highly available & scalable systems, with a focus on asynchronous processing.
• Leverage technology such as Python, Golang, AWS, and Kubernetes to advance Klaviyo's platform, with a deep focus on Apache Pulsar, SQS, and Kafka. 
• Champion best practices by actively collaborating with other teams in a culture that values technical design review.
• Mentor and pair with other Klaviyo engineers to build better software by focusing on performance, self-healing systems, configuration as code, and defensive programming.
• Participate in periodic on-call duties with a focus on solving issues when they are discovered, preventing recurrences and minimizing alert fatigue.

Who You Are:

• You are passionate about building software effectively and for the long term, balancing technical quality, velocity, and business impact.
• BA or BS Degree in Computer Science, related field, or equivalent experience.
• You typically bring 6+ years of hands-on software development experience building and operating highly available, full-stack SaaS products at scale, or have demonstrated equivalent proficiency and impact.
• You are independently responsible for the full lifecycle of complex projects or features, including discovery, technical design, implementation, rollout, and ongoing maintenance. You provide clear technical direction for others involved.
• You own the operational health of the systems you build, including performance, reliability, and observability. You are comfortable defining and upholding SLOs, participating in on-call, and driving follow-through on incidents and RCAs.
• Familiarity with cloud infrastructure (AWS preferred), infrastructure-as-code (Terraform), and containerized environments (Kubernetes), including how to design services that run reliably at scale in those environments.
• Expertise and hands-on experience with asynchronous processing and queueing systems like SQS, Kafka, or Apache Pulsar.
• Ability to handle yourself and complex systems in outage situations and to drive failures to root cause analysis and prevention of future issues.
• 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.
• You question convention and proactively look for ways to improve, whether that’s workflows, architecture, tooling, or team processes. You are intrinsically motivated to drive incremental and step-change improvements that deliver value to the business.
• You are an excellent communicator and collaborator. You lead technical discussions at the project and product-area level, write clear technical design documents and RFCs, and keep stakeholders aligned on progress, risks, and trade-offs.
• You mentor and support other engineers, offering thoughtful feedback in design and code reviews, helping refine specifications, and investing in the growth of more junior engineers on the team.
• You enjoy working on small, autonomous, agile teams, shipping early and often, pairing with product managers, business stakeholders, and other engineers to craft better software.

Nice to Have:

• Fundamental understanding of Linux and all layers of the networking stack; you should be confident administering and debugging production Linux systems.
• Practical experience building high availability systems at scale with Apache Pulsar.

Technologies We Use:

Klaviyo’s platform is primarily built with Python and React and runs on AWS. Engineers join us from a wide range of technical backgrounds and are supported in learning our stack. Core technologies include:

• Python / Django / FastAPI / GoLang
• Protobuf
• Apache Pulsar / Apache Kafka / SQS
• AWS / Terraform / Kubernetes / Argo / Istio / Kong

Location & Work Model:

This role is based in Boston, Massachusetts and follows a hybrid working model. Klaviyo supports work authorization and relocation for this position.

At Klaviyo, we enjoy tackling meaningful engineering challenges and value people who take ownership, learn continuously, and collaborate openly. We are committed to building inclusive teams and encourage applications from candidates of all backgrounds.

Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech

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

Background

Klaviyo operates a real-time data analytics platform coded primarily in Python that is built for massive scale and hosted on Amazon Web Services (AWS). Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

Klaviyo’s Core Data Platform consists of 3 key entities: Profiles (our customer’s customer), Objects (ex: Products & Custom), and Events (the actions taken). Events are the backbone of Klaviyo. Most of our customers view Klaviyo through the lens of events. Events are key to our real time automations, insights and emerging AI feature set. 

At Klaviyo, we love tackling tough engineering problems and look for employees 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. Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech.

How you’ll make an impact:

This team is the backbone of klaviyo’s data platform enabling all our segmentation, flows, and analytics. As an Engineering Manager, you’ll be contributing to the vision, mission, and strategy of Klaviyo’s evolution. You’ll lead and mentor a team of talented and experienced software engineers who are eager to grow fast and make an impact on the company.

What You Will Do

• Lead, manage, and mentor a team of software engineers that designs and develops the event platform
• Own features that thousands of our customers and internal teams rely on daily to drive their business forward
• Coordinate a team of 6-10 engineers to deliver projects that enhance Klaviyo’s event platform capabilities
• Work closely with cross-functional teams to define project scope, requirements, and timelines, and ensure timely and successful project delivery
• Think in systems, help design and improve architectural patterns to ensure they are performant and scalable
• Actively participate in code reviews and contribute to the development of technical solutions to complex problems
• Foster a culture of innovation, continuous learning, and collaboration within the Engineering and Product organizations
• Participate in the technical interview process to help maintain a high bar for our growing teams

What We’re looking for: 

• 10+ years of experience in software development with 3+ years of experience in Engineering Management
• You are passionate about and have proven experience being a coach and a mentor for team members and helping them grow
• You’re a hands-on manager, able to contribute to design documents, write code, and perform code reviews when necessary
• Experience working with internal stakeholders on feature, technical, and architectural specifications
• Proficiency in managing all aspects of PDLC/SDLC and successfully driving complex projects to completion
• Experience working with data storage technologies and patterns, including distributed storage, data modeling, and relational databases
• You have architected, built and delivered at least one complex data processing system
• Experience with large scale data pipelines and real time data ingestion
• You know how to apply off-the-shelf technologies to solve technical problems, and know when it’s time to build your own
• Excellent communication and interpersonal skills

Nice to have:

• Experience working with both monolithic and microservices architectures
• Experience debugging performance issues and improving system performance
• Experience working with cloud technologies (AWS, GCP, Azure)

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

#IndeedRD

• Lead and manage a team of full-stack and AI engineers and directly manage some workstreams yourself.
• Collaborate on project planning, define achievements, identify dependencies, and ensure business goals are met.
• Actively participate in interviewing, hiring, and team leveling.
• Develop SMART goals and career development plans for direct reports.
• Develop and execute technical strategies aligned with Klaviyo's business goals, ensuring exceptional products and a reliable, user-friendly AI systems roadmap.
• Engage with internal and external stakeholders to understand needs, resolve blockers, manage expectations, and translate customer needs into valuable AI-driven roadmaps and solutions.
• Advise the team on modeling, system design, experimental design, and implementation decisions.
• Improve engineering-wide processes such as recruiting, performance development, communication, and agile development.
• Stay current with emerging AI trends and technologies, identifying and leveraging opportunities within Klaviyo’s ecosystem.

• Experience building AI-driven product features in a full-stack capacity and leading teams who have built scaled systems.
• 5+ years of experience in software engineering, 2+ years of experience  managing engineering teams, including remote members and lead engineers.
• Exceptional communication skills, capable of collaborating with diverse stakeholders to translate business/product roadmaps into AI-driven technical roadmaps and solutions that add significant customer and business value.
• Motivated to grow the team through developing current members and attracting new talent to expand capabilities.
• Eager to engage with code, understand the product area, and provide applicable technical mentorship.
• In-depth understanding of common engineering architectures for highly scalable systems.
• Proven ability to lead and deliver complex, multi-quarter projects involving at least two teams.
• Comfortable conducting performance reviews and mentoring team members at all levels.

• We love recovering entrepreneurs. If you’ve ever run your own thing, you’ll have company on our team.

Boston, MA - Hybrid Role

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

Why you should join the SMS International team that is part of Mobile Platforms

The Mobile Platforms team at Klaviyo is responsible for empowering the over 150,000 Ecommerce clients we work with on a global scale to deliver effective experiences on mobile devices. This team focuses on performance optimization and continuous development of our Mobile Marketing Channels (SMS, Push Notifications, In App Messages, WhatsApp and RCS), Mobile SDKs (iOS, Android and React Native). While Email was how Klaviyo began, Mobile messaging is truly the way of the future.

The SMS International team within Mobile Platforms is responsible for the expansion of SMS capabilities into new countries and regions and is also spearheading the development of RCS as a new capability to be offered to customers alongside existing channels. We have an ambitious roadmap for 2026 that puts the team at the heart of the company’s objectives and it is an exciting time to join the team!

About the Role

As a Fullstack Software Engineer II joining the SMS International team you will be working with a team of 5 other colleagues to deliver RCS and SMS International expansion to meet the company’s objectives. You will get the chance to build brand new services, understand how they fit into the bigger picture and plan how to architect and scale them successfully to serve our customers. 

Technologies we use (not exhaustive):

• Python, Django, Go, React, SQS, Celery, MySQL, DynamoDB, Elasticache, Redis
• Amazon Web Services (EC2, RDS, Aurora, etc.), Terraform, Kubernetes, Splunk, Buildkite, Grafana, Chronosphere and other modern DevOps tools

What we are looking for

• 3-5 years of experience in a software engineering discipline
• Experience with full stack application development
• Experience working with both monolithic and microservices architectures
• Experience with database design that can withstand high query volumes
• Experience with CI/CD pipelines
• Experience debugging performance issues and improving application performance
• An interest and aptitude for collaboration across teams and disciplines

Nice to Have

• Experience creating new services with scalability in mind. Exposure to large-scale system design
• Experience with AWS or any similar cloud provider
• Communication domain experience

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

The Catalog Insights Team’s mission is to arm Klaviyo customers with the data they need to drive sustainable business growth through efficient and effective product placement. Beyond analytical views, this team is also highly focused on actionability: finding creative ways for customers to go from catalog insight to revenue-driving marketing action in a matter of clicks.

As an Engineer on the Catalog Insights team you can expect to be deeply involved in the technical discussions and delivery of the features our customers need. You'll have ownership of projects that contribute to the team's mission, goals, and roadmap. You'll collaborate alongside technical product owners and product managers to build a product and develop a technical strategy to deliver products that make it easy for users to understand their data and performance. Your tech stack will include Python, Typescript, React, AWS, Kubernetes, Django, and Spark. 

How You Will Make A Difference

• Deliver key product capabilities for Catalog Insights to support our recently launched Marketing Analytics product.
• Design and build systems and data pipelines that process large volumes of data to deliver experiences providing value to Klaviyo customers of all sizes
• Work cross functionally with product, design, and data science teams to develop product requirements and technical solutions.
• Own product solutions end-to-end, including technical design, implementation, maintenance, monitoring, and participation in on-call rotations for the services we ship.
• Have ample opportunities for growth. 

Who You Are

• 2+ years experience working in a SaaS product in full stack capacity
• Proficient in at least one modern programming language
• Degree or equivalent experience in a software engineering discipline
• Able to communicate well
• Able to work with others on a team
• Able to learn continuously and adapt to a high growth environment
• Able to stick with and solve difficult problems
• Excited to learn and understand data visualization in addition to full stack engineering

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

Team Overview:

The Amplify Engineering team builds internal tools, platforms, and AI-powered automation that help Klaviyos work more efficiently and at scale as the company grows. We partner across the organisation, including Sales, Marketing, Engineering & Product, Customer Service & Success, and Finance, to solve real operational problems with practical, well-designed software.

Our work spans internal applications, 3rd-party integrations, interactive dashboards, CMS integrations, and robust AI systems and agents that automate repetitive tasks, surface the right information at the right time, and help teams make better decisions. We operate in tight feedback loops with our internal customers, shipping quickly, learning fast, and seeing the impact of our work immediately in how deals move faster, tickets resolve sooner, and launches go more smoothly.

This role is for software engineers who enjoy turning real-world problems into reliable, scalable solutions. The work is highly visible and has a direct impact on how thousands of Klaviyos get their work done every day.

How You’ll Make an Impact:

The Amplify team builds the internal platforms, automation, and AI-driven systems that power how Klaviyos work every day. As an AI Software Engineer II on Amplify, you will:

• Design, build, and maintain internal products and platforms, including internal web applications, APIs, data and event pipelines, and AI-powered workflows used daily by Sales, Marketing, Customer Service & Success, R&D, and Finance teams. You will own features and small-to-medium projects end to end, from design through deployment and iteration.
• Deliver project work with increasing autonomy and scope. You will break down problems into actionable pieces, refine requirements with your team, and collaborate to ship high-quality solutions that meet reliability and performance expectations.
• Work closely with internal customers to understand their workflows and constraints, and translate operational challenges into pragmatic, maintainable software and AI-enabled tools that improve productivity and reliability.
• Contribute to the technical and architectural evolution of Amplify’s systems by participating in design discussions, proposing improvements, and helping ensure our platforms remain scalable, observable, and reliable as usage grows.
• Take responsibility for the quality and operational health of the code you ship, including testing, deployment, monitoring, debugging issues in development and production, and participating in on-call rotations for the systems your team owns.
• Use modern AI tools as part of your day-to-day engineering workflow, including for coding, testing, documentation, and experimentation, and share learnings to help the team continuously improve how it works with AI.
• Help improve the developer experience and engineering practices on Amplify by contributing to tooling, CI/CD, automation, tests, and shared utilities that support consistent, high-quality delivery.
• Collaborate closely with Product, Design, Data, and operational partners, contributing to discovery, evaluating trade-offs, and ensuring the work you deliver is tied to clear success criteria and business outcomes.

Who You Are:

• You care about building software for the long term, balancing technical quality, delivery pace, and business impact.
• You have strong hands-on experience building and operating full-stack or backend-focused software systems, including SaaS products, platforms, or internal tools.
• You can take a well-defined feature or small-to-medium project from design through implementation, testing, rollout, and ongoing maintenance, seeking input when needed and moving work forward independently.
• You are comfortable questioning and refining requirements, working with product managers and stakeholders to clarify scope, identify edge cases, and propose pragmatic solutions.
• You have experience in at least one area of modern web engineering such as backend services, data pipelines, internal tools, integrations, or AI-enabled workflows, and understand how to build secure, scalable, and maintainable systems.
• You are comfortable using AI-powered tools to support your development workflow and are interested in continuing to grow your AI skills over time.
• You care about operational excellence and are comfortable debugging issues, improving tests, adding logging and metrics, and working within reliability goals.
• You are a clear communicator and collaborative teammate, contributing thoughtfully to technical discussions, writing clear tickets or lightweight design docs, and keeping others informed on progress and risks.
• You enjoy working in small, autonomous, agile teams, shipping iteratively, and partnering closely with product managers and other engineers to deliver meaningful outcomes.
• You are motivated to continuously improve how things work, whether that is tooling, workflows, architecture, or team practices.

Nice to Have:

• Experience building internal tools, platforms, or automations for developers and/or non-technical stakeholders, with a track record of improving reliability, productivity, or operational efficiency.
• Hands-on experience in full-stack environments, including diagnosing and improving application performance, database queries, and complex, multi-service workflows.
• Practical experience building or integrating AI-powered systems and agents; e.g., workflows using LLM APIs/SDKs, agentic or automated workflows, RAG pipelines, or evaluation/monitoring frameworks.
• Familiarity with cloud infrastructure (AWS preferred), infrastructure-as-code (Terraform), and containerized environments (Kubernetes), including how to design services that run reliably at scale in those environments.

Technologies We Use:

Klaviyo’s platform is primarily built with Python and React and runs on AWS. Engineers join us from a wide range of technical backgrounds and are supported in learning our stack. Core technologies include:

• Python / Django / FastAPI
• Typescript / React
• MySQL / Redis / Memcached
• RabbitMQ / Celery / Apache Kafka / Apache Pulsar
• AWS / Terraform / Kubernetes

Location & Work Model:

This role is based in Dublin, Ireland and follows a hybrid working model. Klaviyo supports work authorization and relocation for this position.

At Klaviyo, we enjoy tackling meaningful engineering challenges and value people who take ownership, learn continuously, and collaborate openly. We are committed to building inclusive teams and encourage applications from candidates of all backgrounds.

Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech

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

Team Overview:

The Amplify Engineering team builds internal tools, platforms, and AI-powered automation that help Klaviyos work more efficiently and at scale as the company grows. We partner across the organisation, including Sales, Marketing, Engineering & Product, Customer Service & Success, and Finance, to solve real operational problems with practical, well-designed software.

Our work spans internal applications, 3rd-party integrations, interactive dashboards, CMS integrations, and robust AI systems and agents that automate repetitive tasks, surface the right information at the right time, and help teams make better decisions. We operate in tight feedback loops with our internal customers, shipping quickly, learning fast, and seeing the impact of our work immediately in how deals move faster, tickets resolve sooner, and launches go more smoothly.

This role is for lead engineers who enjoy turning real-world problems into reliable, scalable solutions. The work is highly visible and has a direct impact on how thousands of Klaviyos get their work done every day.

How You’ll Make an Impact:

The Amplify team builds the internal platforms, automation, and AI-driven systems that power how Klaviyos work every day. As a Lead AI Software Engineer on Amplify, you will:

• Provide technical oversight and direction for a portfolio of Amplify systems, including internal web applications, APIs, data and event pipelines, and AI-powered workflows used daily by Sales, Marketing, Customer Service & Success, R&D, and Finance teams. You will help ensure they are reliable, scalable, secure, and straightforward to evolve.
• Formulate and drive a forward-looking technical vision for key Amplify domains in partnership with your Engineering Manager, Product, Data, and cross-functional stakeholders, aligning that vision with our AI-first strategy and the business outcomes we are accountable for.
• Lead the end to end lifecycle of complex, multi component projects and platforms that span multiple internal customers and engineering teams, from discovery and technical design through implementation, rollout, and long term ownership.
• Act as the primary technical interface between your areas of ownership in Amplify and the rest of engineering, helping clarify requirements, reduce technical ambiguity and risk, and ensure the team delivers roadmap and OKR commitments on time with the right quality bar.
• Take responsibility for the technical and architectural evolution of multiple significant domains within Amplify, anticipating scalability, reliability, security, and observability needs as usage grows and new use cases emerge.
• Define, refine, and uphold operational standards for the systems you and your team own, including SLOs, monitoring and alerting, incident response practices, and post incident learning that continually improves our operational excellence.
• Create, teach, and improve shared engineering processes, patterns, and internal platforms that make it easier for Amplify and other teams across Klaviyo to build high quality internal tools and AI-powered systems consistently.
• Use modern AI tools as part of your day-to-day engineering workflow and help the team adopt AI effectively, from design and coding through testing, documentation, and evaluation. You will help establish sensible guardrails, evaluation practices, and patterns for AI-first development.
• Work through influence and delegation to get work done, setting clear technical direction, breaking down projects into actionable workstreams, and enabling other engineers to deliver successfully.
• Mentor and coach other engineers across levels through design reviews, pairing, and thoughtful feedback. You will help grow future technical leaders, raise the technical bar for the team, and ensure knowledge is shared rather than concentrated.
• Collaborate closely with Product, Design, Data, and operational partners to define problems, shape trade offs, and agree on success metrics, ensuring Amplify’s work focuses on the highest value opportunities and that outcomes are clearly measured.
• Represent Amplify’s systems and strategy in broader engineering forums, contributing to architectural discussions, technical RFCs, and cross team initiatives, and helping ensure our internal platforms fit well into the wider Klaviyo ecosystem.

Who You Are:

• You care deeply about building software and platforms for the long term, balancing technical quality, delivery pace, and measurable business impact, and you are comfortable making and explaining trade offs at that intersection.
• You have strong hands on experience building and operating highly available, full stack or backend focused SaaS systems, and have been responsible for the health and evolution of multiple services or product areas, not just a single application.
• You have led delivery of business critical projects that span multiple engineers and months, including discovery, technical design, implementation, rollout, and ongoing maintenance. You are comfortable scrutinising requirements, reducing ambiguity, and setting technical direction for others.
• You have deep expertise in several areas of modern web engineering such as backend services, data pipelines, internal platforms, or AI enabled systems, and a strong understanding of scalable, multi-tenant architectures and the operational realities of running them in production.
• You regularly use AI powered tools in your development workflow and are interested in shaping how a team or organisation uses AI thoughtfully to improve engineering productivity, system capabilities, and internal customer experiences.
• You take ownership of operational excellence for the systems you and your team build, including performance, reliability, observability, and on-call participation where required. You are comfortable defining and maintaining SLOs and holding systems to them.
• You are effective at working through influence and delegation. You know when to keep a task for yourself and when to hand it to others, and you enjoy creating the clarity, patterns, and guardrails that let other engineers move quickly and safely.
• You enjoy questioning convention and continuously improving how things work, whether that is architecture, tooling, workflows, or team processes, and you are comfortable introducing change in a way that brings people along with you.
• You are a clear communicator and collaborative teammate, comfortable leading technical discussions, writing design docs or RFCs, and keeping stakeholders aligned from early discovery through delivery and follow up.
• You enjoy working in small, autonomous, agile teams, shipping incrementally, and partnering closely with product managers, data partners, and other engineers to deliver better outcomes for internal customers.

Nice to Have:

• Experience building internal tools, platforms, or automations for developers and or non technical stakeholders, with a track record of improving reliability, productivity, or operational efficiency across multiple teams.
• Experience providing technical leadership across several related systems or domains, including defining technical vision, setting design patterns, and aligning multiple teams on shared approaches.
• Practical experience building or integrating AI powered systems and agents such as workflows using LLM APIs or SDKs, agentic or automated workflows, retrieval augmented generation pipelines, or evaluation and monitoring frameworks for AI systems.
• Experience working with cloud infrastructure (AWS preferred), infrastructure as code (Terraform), and containerised environments (Kubernetes), and designing services that run reliably at scale in those environments.
• Experience partnering closely with customer service & support, go to market, or operations teams to understand complex workflows and build internal tools that drive measurable efficiency gains.

Technologies We Use:

Klaviyo’s platform is primarily built with Python and React and runs on AWS. Engineers join us from a wide range of technical backgrounds and are supported in learning our stack. Core technologies include:

• Python / Django / FastAPI
• Typescript / React
• MySQL / Redis / Memcached
• RabbitMQ / Celery / Apache Kafka / Apache Pulsar
• AWS / Terraform / Kubernetes

Location & Work Model

This role is based in Dublin, Ireland and follows a hybrid working model. Klaviyo supports work authorization and relocation for this position.

At Klaviyo, we enjoy tackling meaningful engineering challenges and value people who take ownership, learn continuously, and collaborate openly. We are committed to building inclusive teams and encourage applications from candidates of all backgrounds.

Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech

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

#indeedDUB

Team Overview:

The Amplify Engineering team builds internal tools, platforms, and AI-powered automation that help Klaviyos work more efficiently and at scale as the company grows. We partner across the organisation, including Sales, Marketing, Engineering & Product, Customer Service & Success, and Finance, to solve real operational problems with practical, well-designed software.

Our work spans internal applications, 3rd-party integrations, interactive dashboards, CMS integrations, and robust AI systems and agents that automate repetitive tasks, surface the right information at the right time, and help teams make better decisions. We operate in tight feedback loops with our internal customers, shipping quickly, learning fast, and seeing the impact of our work immediately in how deals move faster, tickets resolve sooner, and launches go more smoothly.

This role is for senior engineers who enjoy turning real-world problems into reliable, scalable solutions. The work is highly visible and has a direct impact on how thousands of Klaviyos get their work done every day.

How You’ll Make an Impact:

The Amplify team builds the internal platforms, automation, and AI-driven systems that power how Klaviyos work every day. As a Senior AI Software Engineer on Amplify, you will:

• Design, build, and own complex internal products and platforms, including internal web applications, APIs, data and event pipelines, and AI-powered workflows used daily by Sales, Marketing, Customer Service & Success, R&D, and Finance teams.
• Lead the end-to-end lifecycle of projects and features – from discovery and technical design through implementation, rollout, and long-term ownership.
• Partner closely with internal customers to understand their workflows and constraints, and translate real operational challenges into scalable, maintainable solutions that measurably improve productivity, quality, and reliability.
• Take ownership of the technical and architectural evolution of parts of the Amplify platform, anticipating scalability, reliability, and observability needs as usage grows.
• Define and maintain operational standards for the systems you own, including SLOs, monitoring, incident response, and follow-up on root-cause analysis.
• Use modern AI tools as part of your day-to-day engineering workflow (e.g. LLM-based tooling for design, coding, testing, and documentation), and help shape best practices for how the team applies AI responsibly and effectively.
• Contribute to shared patterns, tooling, and processes that make it easier for teams across Klaviyo to build high-quality internal tools and AI-powered systems consistently.
• Mentor and support other engineers through design reviews, pairing, and constructive feedback, leaving the codebase and systems better than you found them.
• Collaborate closely with Product, Design, Data, and operational partners to define requirements, trade-offs, and success metrics, ensuring Amplify’s work focuses on the highest-value problems.

Who You Are:

• You care deeply about building software for the long term, balancing technical quality, delivery pace, and business impact.
• You have strong hands-on experience building and operating highly available, full-stack SaaS systems, and are comfortable owning complex problems end to end.
• You’ve led the delivery of significant projects or features independently, including discovery, technical design, implementation, rollout, and ongoing maintenance, and you’re comfortable providing technical direction to others.
• You have deep expertise in one or more areas of modern web engineering (e.g. backend services, data pipelines, internal platforms, or AI-enabled systems) and a solid understanding of scalable, multi-tenant architectures.
• You regularly use AI-powered tools in your development workflow and are curious about applying AI thoughtfully to improve engineering productivity and system capabilities.
• You take ownership of operational excellence for the systems you build, including performance, reliability, observability, and on-call participation where required.
• You enjoy questioning convention and continuously improving how things work, whether that’s architecture, tooling, workflows, or team practices.
• You are a clear communicator and collaborative teammate, comfortable leading technical discussions, writing design docs or RFCs, and keeping stakeholders aligned.
• You enjoy working in small, autonomous, agile teams, shipping incrementally, and partnering closely with product managers and other engineers to deliver better outcomes.

Nice to have:

• Experience building internal tools, platforms, or automations for developers and/or non-technical stakeholders, with a track record of improving reliability, productivity, or operational efficiency.
• Hands-on experience in full-stack environments, including diagnosing and improving application performance, database queries, and complex, multi-service workflows.
• Practical experience building or integrating AI-powered systems and agents; e.g., workflows using LLM APIs/SDKs, agentic or automated workflows, RAG pipelines, or evaluation/monitoring frameworks.
• Experience working with cloud infrastructure (AWS preferred), infrastructure-as-code (Terraform), and containerised environments (Kubernetes), and designing services that run reliably at scale.

Technologies We Use:

Klaviyo’s platform is primarily built with Python and React and runs on AWS. Engineers join us from a wide range of technical backgrounds and are supported in learning our stack. Core technologies include:

• Python / Django / FastAPI
• Typescript / React
• MySQL / Redis / Memcached
• RabbitMQ / Celery / Apache Kafka / Apache Pulsar
• AWS / Terraform / Kubernetes

Location & Work Model:

This role is based in Dublin, Ireland and follows a hybrid working model. Klaviyo supports work authorization and relocation for this position.

At Klaviyo, we enjoy tackling meaningful engineering challenges and value people who take ownership, learn continuously, and collaborate openly. We are committed to building inclusive teams and encourage applications from candidates of all backgrounds.

Klaviyo is growing fast and we have openings for all skill levels across all of our teams. Learn more about our engineering culture at https://klaviyo.tech

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

Job Title: Senior Software Engineer - Marketing Agent

Location: Boston, MA (Hybrid 3x week)

At Klaviyo, we believe the future of software lies not in productivity tools for human users but in systems that do the hard work for them. We’ve built the infrastructure and applications that power the interface between businesses and consumers — supporting over 183,000+ customers, billions of consumer profiles, and hundreds of billions of customer interactions. Now, we’re building the next generation of AI agents that can automatically create, execute, and optimize marketing and customer experience strategies for any business.

As a Senior Software Engineer on Klaviyo's Marketing Agent team, you'll be at the forefront of one of the most impactful bets we're making — building an AI-powered system that autonomously creates and executes high-stakes marketing strategies on behalf of thousands of customers. This isn't backend plumbing: the work you ship directly drives revenue for the businesses that rely on Klaviyo every day. Partnering closely with product managers and technical product owners, you'll shape the scope of what's possible, turn ambitious ideas into production reality, and craft tools so intuitive they feel like superpowers to the marketers using them.

This role is primarily backend, with a strong focus on crafting robust and maintainable AI powered systems that deliver high quality strategies and marketing content that’s ready to use to our customers. There are ample opportunities for growth given the scope of this role and the team’s central role in Klaviyo’s product.

How you’ll make a difference:

• You will dramatically increase ROI for Klaviyo customers by automating most of the marketing process for them.
• You will lead and design the next generation of agentic systems at Klaviyo, pushing the frontier of AI capabilities.
• You will collaborate with AI Engineers and AI Infra Engineers to ensure our system consistently produces high quality outputs at low latency.
• You will leverage your experience to mentor and level up junior team members on engineering best practices and patterns.
• You will transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up.

Who you are: 

• A proven track record of building high-quality products and systems, with pride in writing clean, high-quality code.
• 6+ years of experience in a software engineering role.
• Experience leading projects and being accountable for their outcomes.
• Experience mentoring team members or driving initiatives that help the team learn new skills.
• Experience conducting code reviews and running a robust testing cycle.
• Experience working in agile, fast-paced environments.
• Proficient in Python and modern web stack components such as FastAPI, Django, MySQL, Postgres.
• Experience working in cloud environments (AWS preferred).
• 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.

 Nice to have: 

• Prior work experience with AI tools such as Arize, Langgraph, Langchain
• Prior work experience building with LLMs such as GPT, Gemini, Claude

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

At Klaviyo, we believe the future of software lies not in productivity tools for human users but in software that can run and optimize itself based on outcome or reward metrics. We’ve built the infrastructure and application that serve as the interface between businesses and consumers. We now have over 167,000 customers, billions of consumer profiles, and hundreds of billions of customer messages and follow-on conversion data. We have a big opportunity to build state-of-the-art AI and machine learning technologies at Klaviyo to power our products and develop AI agents that can automatically create and execute marketing or customer experiences, strategies, and campaigns for any business.

As a Sr. AI Engineer at Klaviyo, you’ll play a key role in designing and building scalable backend systems and user experiences that power our AI products and AI agent solutions. You’ll partner closely with product managers, machine learning engineers, and data scientists, to drive real-world impact at scale. This is a backend-heavy role with opportunities to influence architecture, async processing pipelines, distributed systems, and more.

How You Will Make a Difference

• Design and build backend systems that support scaling our AI solutions for 167K+ customers.

• Develop robust, reliable and scalable data collection and processing pipelines for machine learning models to train and consume.

• Develop robust, reliable and scalable services to serve AI models in production environments.

• Contribute to evolving our agentic architecture — making our AI agents more self-sufficient and performant.

• Contribute to a culture of ownership, experimentation, and customer-centric product thinking.

Who You Are

• 5–7 years of professional experience in software engineering, with a strong focus on backend systems and distributed architectures.

• Have hands-on experience building and deploying generative AI and agentic AI applications into production, with expertise in prompt engineering, few-shot learning, fine tuning and evaluation.

• Experienced backend engineer with a strong track record of building scalable, distributed systems, especially in the service of AI agent capabilities.

• Proficient in Python and modern backend frameworks (FastAPI, Django preferred).

• Experience creating human and automated evals to ensure high AI model quality.

• Proficient in big data tools such as Apache Spark and Hadoop.

• Deep experience with asynchronous processing and distributed task queues (Celery, Kafka, SQS, RabbitMQ, Redis).

• Strong understanding of database technologies and ORMs (SQLAlchemy, Alembic).

• Comfortable with cloud-native architectures (AWS) and container orchestration (Kubernetes); can manage infrastructure and CI/CD pipelines.

• Skilled at designing and building robust APIs.

• Able to operate with a high degree of autonomy, handle ambiguity, and thrive in a fast-moving, startup-like environment.

• Driven by curiosity. You're someone who learns and stays up to date with this rapidly evolving field.

• Comfortable collaborating directly with product managers and customers to shape solutions.

Nice to Have

• Trained ML models in the past and deployed them in production systems to generate impact to businesses.

• Experience in reinforcement learning.

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

About Klaviyo

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.

About the Team

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.

As a Senior Lead Software Engineer within the Messaging Infra organization, you will serve as the primary technical architect for our high-volume message delivery systems while driving the overarching technical vision for channel expansion. You will partner with leaders across all channels to ensure a scalable, reliable, and performant platform strategy, acting as a key technical liaison to the broader Mobile Channels and Messaging Infrastructure pillar. Your leadership will ensure that our core systems are not just maintained, but architected to accelerate innovation and business impact while raising the bar on scalability and reliability.

What You'll Do

As a Senior Lead Software Engineer, you will have an overarching responsibility for the architecture, health, and scaling of the Messaging Infra platform with a focus on high-volume message delivery. Your role will involve:

• Technical Strategy: Define the technical strategy and architectural vision for the Messaging Infra platform, ensuring all system improvements align with long-term business goals for massive scalability, high reliability, and low latency message delivery.
• System Architecture and Improvement: Serve as the primary architect to build and improve high-volume message delivery systems across multiple channels, focusing on throughput, performance, and reliability.
• Cohesive Technical Vision: Drive technical leadership to guide architectural decisions across multiple teams, striving towards a cohesive technical vision across multiple roadmap items and providing solutions for complex problems around scalability and performance.
• Platform Rollouts and Product Execution: Oversee and execute the planning and seamless rollout of major software releases and updates for the platform, managing the entire lifecycle from design to deployment in production environments including significant individual contributions.
• Problem Solving and Reliability: Act as a go-to expert for diagnosing and resolving complex performance, scalability, and reliability issues across the messaging platform. Implement proactive monitoring and telemetry to identify and address problems before they become critical incidents.
• Mentorship: Mentor other engineers regularly, primarily experienced lead and senior engineers, to develop new technical leadership for the company.
• Cross-functional Collaboration: Partner with product managers, deliverability and compliance specialists, and other stakeholders to gather requirements, resolve conflicts, and ensure alignment across all teams and projects.
• Continuous Improvement: Stay current with emerging technologies and industry trends, evaluating new tools and practices to identify how they can improve systems and internal processes.

Who You Are

• 12 years of experience in software development, strong knowledge of computer science fundamentals, domain-driven design, and extensive expertise in architectural patterns, specifically within the domain of distributed systems.
• Have proven that you can build and scale complex distributed systems, including solving problems in sustainable ways, balancing pragmatic development with ideal architecture, breaking through technical obstacles with vigor, and leading teams through crises by working side by side with them in the trenches.
• BA or BS Degree in Computer Science, related field, or equivalent experience.
• Technical Expertise: Deep expertise in relevant programming languages (e.g., Python, Go) and cloud platforms (AWS, Azure, GCP), containerization (Kubernetes, Docker), and Infrastructure as Code (Terraform). You are particularly passionate and an expert in multiple stack areas, with strong and opinionated experience with various technologies, and know how to pick the right tool for any job.
• Technical Strategy: Demonstrated experience in contributing to the product and platform vision, as well as defining the strategy within the broader scope of long-term organizational needs.
• Architectural Skills: Strong understanding of software architecture, design patterns, and system integration, with the ability to define technical strategies and influence architectural decisions across multiple teams.
• Soft Skills: Exceptional problem-solving, analytical, leadership, and communication skills, with the ability to articulate complex technical concepts to both technical and non-technical audiences.
• AI Enthusiast: 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 efficiently.

Nice to Have

• Experience with the email and/or SMS ecosystem, including understanding of channel-specific protocols and security specifications (e.g., DKIM, DMARC, SPF), and familiarity with key 3rd-party entities (like mailbox providers, anti-abuse groups, and telecoms) and compliance rules/best practices.
• Background in performance optimization and a passion for digging into performance and scalability issues to drive breakthrough solutions.
• Familiarity with complex data management for testing, including large datasets and production-like data replication.

Our Tech Stack

• Python, Django, FastAPI, Celery
• Apache Kafka, Apache Pulsar, RabbitMQ, Spark, Airflow, and other tech from the big data stack
• MySQL, PostgreSQL, Clickhouse, Cassandra, Redis
• Typescript, React, Backbone.js, HTML, JavaScript, Babel, Jest, Webpack
• Graphite, statsd, Chronosphere
• AWS (EC2, RDS, Aurora, etc.), Terraform, Docker, Kubernetes (EKS), Pantsbuild, Argo, and other modern DevOps 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

Lead Software Engineer, Reliability (Dublin)

Team Overview

As a Lead Software Engineer, Reliability, you will set technical direction and lead reliability strategy for Klaviyo’s most critical platforms. You’ll ensure our systems are reliable, scalable, and sustainable while enabling rapid product development across the company.

We treat reliability as a core product feature. Our work spans security, infrastructure, and software engineering, requiring deep systems thinking and strong technical leadership. We build foundational services that must be extremely reliable, secure, and performant at global scale.

The SRE team’s charter is to design, build, and operate foundational infrastructure and services, define reliability standards, reduce operational toil through automation, and continuously improve systems based on production learnings. As a lead, your work will be highly visible and will directly influence how Klaviyo builds software and how customers experience our platform every day.

How you’ll make an impact

As a Lead Software Engineer, Reliability, you will provide technical leadership while remaining hands-on with the systems that underpin Klaviyo’s reliability and operational excellence. You will:

• Set the technical vision and long-term strategy for reliability, availability, and operational excellence across critical platforms
• Lead the design, implementation, and evolution of foundational, security-critical services with strong guarantees around availability, scalability, latency, and fault tolerance
• Drive adoption of SRE best practices across engineering teams, including SLIs, SLOs, error budgets, and reliability-based decision making
• Identify systemic reliability risks and architectural bottlenecks, and lead cross-team initiatives to address them with durable, preventative solutions
• Apply software engineering principles to automate infrastructure, eliminate operational toil, and improve system reliability at scale
• Own and continuously improve observability, alerting, and incident response practices to reduce mean time to detection and recovery
• Guide on-call strategy and operational processes to ensure sustainability, automation, and healthy operational load
• Perform and lead quantitative analysis around system behavior, capacity planning, scaling limits, and performance characteristics
• Partner closely with product, platform, and security leaders to influence system architecture early and ensure reliability is built in from the start
• Lead incident response for high-severity events, driving effective mitigation, communication, and follow-up
• Mentor senior and mid-level engineers, raising the bar for technical quality, operational maturity, and reliability culture across the organization
• Review and influence technical designs, platform APIs, operational runbooks, and system documentation at an organizational level
• 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.

Who you are

You are a senior technical leader who combines deep systems expertise with strong judgment and influence. You:

• Are a cloud-native, platform-focused SRE who uses software to design and operate highly reliable production systems at scale
• Write and maintain production-quality code (e.g. Python, Go, or similar) to build internal platforms, automate operations, and improve system reliability
• Have led the design and operation of distributed, cloud-native systems and deeply understand failure modes such as partial outages, dependency failures, resource saturation, and cascading impact
• Have extensive experience operating containerized workloads and platforms (e.g. Kubernetes) in production, including deployment strategies, scaling behavior, and service networking
• Are comfortable owning on-call strategy and participating in escalation for complex production incidents
• Have designed and evolved observability platforms and alerting strategies that reflect real customer and service impact
• Apply SRE concepts such as SLIs, SLOs, error budgets, and burn-rate–based alerting to guide engineering priorities and trade-offs at a team or org level
• Have strong hands-on experience with infrastructure as code and declarative configuration (e.g. Terraform, Kubernetes manifests, policy-as-code)
• Have led capacity planning, load testing, and performance analysis efforts for large-scale distributed systems
• Drive high-quality post-incident reviews and ensure concrete, code-focused follow-up actions are delivered and sustained
• Are comfortable leading technical discussions, influencing architecture, and providing clear guidance across multiple teams

Nice to have

• Experience leading or supporting critical platforms or internal tooling
• Familiarity with identity, access management, secrets management, or policy enforcement systems
• Experience operating systems at scale in cloud environments (AWS preferred)
• Background in resilience testing, fault injection, or chaos engineering
• Strong understanding of algorithms and data structures as they apply to large-scale systems

Tech Stack

Klaviyo’s platform is primarily built with Python and React and runs on AWS. Engineers join us from a wide range of technical backgrounds and are supported in learning our stack.

Core technologies include:

• Python / Django / FastAPI
• MySQL / Redis / Memcached
• RabbitMQ / Celery / Apache Kafka / Apache Pulsar
• AWS / Terraform / Kubernetes

Location & Work Model

This role is based in Dublin, Ireland and follows a hybrid working model. Klaviyo supports work authorization and relocation for this position.

At Klaviyo, we enjoy tackling meaningful engineering challenges and value people who take ownership, learn continuously, and collaborate openly. We are committed to building inclusive teams and encourage applications from candidates of all backgrounds.

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

Klaviyo’s mission is to help businesses own their growth. AI is at the center of that mission — and we’re building the engineering organization to match. As Director, Engineering – AI, you’ll lead the teams turning our AI strategy into real, daily leverage for hundreds of thousands of customers: from the underlying AI platform and agent framework to the product experiences embedded throughout Klaviyo.

You’ll own the technical vision and execution strategy for AI-powered capabilities across Klaviyo’s product surface, partnering deeply with Product, Design, ML, Data Science, and GTM to define what to build, ship it quickly and safely, and measure real impact in customer outcomes — not just model demos. This is a hands-on, execution-first role for a product-minded engineering leader who is fluent in modern LLMs, agent patterns, and what it takes to bring AI capabilities to production at scale.

How You’ll Make a Difference

• Own the AI engineering charter. Define the technical vision and roadmap for AI-powered capabilities on Klaviyo’s platform, and translate it into clear plans, OKRs, and milestones for your teams.
• Design and evolve the AI platform. Lead the architecture for LLM-powered and agentic systems — orchestration, tool/function calling, retrieval and memory, evaluation harnesses, observability, and safety guardrails tuned for real-world product workflows.
• Ship remarkable, AI-native product experiences. Partner with Product, Design, and partner engineering teams to prioritize the highest-value use cases, break them into shippable iterations, and launch experiences that feel intuitive and powerful — not just demos bolted onto existing UI.
• Make safety, reliability, and measurability non-negotiable. Define success metrics and guardrails for AI systems (e.g., time-to-first-value, uplift over baselines, override rates, hallucination/error rates, latency, SLOs), and build the tooling to monitor and continuously improve them in production.
• Integrate deeply with Klaviyo’s data and platform stack. Collaborate with Data Platform, Production Infrastructure, and product engineering teams to ensure AI systems can safely and efficiently access the right data while respecting privacy, security, and governance constraints.
• Raise the bar on AI engineering craft. Build shared patterns, libraries, and best practices for prompt and chain design, evaluation, human-in-the-loop review, and observability that other teams can reuse; champion rigorous experimentation, A/B testing, and fast feedback loops.
• Lead high-performing engineering teams (ICs and managers). Hire, develop, and retain high-performing, inclusive teams; set crisp expectations, coach for impact, and create a culture of urgency, accountability, and psychological safety.
• Partner across Klaviyo to land changes. Work closely with GTM, Support, and Customer Success to roll out new AI capabilities safely, enable the field, and close the loop between customer feedback, product decisions, and system improvements.
• Measure what matters. Own a clear scorecard for your area — adoption, activation, uplift vs. baselines, quality/satisfaction, AI system reliability, and developer velocity — and use it to drive prioritization and investment decisions.
• Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up, and continuously experimenting with AI tools — testing, learning, and sharing insights to keep Klaviyo ahead of the curve.

Who You Are

• An experienced, product-minded engineering leader. ~10+ years in software engineering, including 5+ years leading multiple teams and managers building user-facing products in high-growth SaaS or similar environments. You’re energized by building things customers love, not just infrastructure for its own sake.
• Hands-on with modern AI and agentic systems. You’ve led teams building with LLMs, retrieval-augmented generation, or agent frameworks — designing multi-step flows, tool calling, memory, evaluation, and safety guardrails — even if you’re not coding every day.
• A deep systems and product thinker. You can dive into architecture and data flows, but also reason from first principles about customer workflows, jobs-to-be-done, and where AI can produce step-change improvements vs. incremental shortcuts.
• An outcome-oriented operator. You define clear success metrics and hold teams accountable to them; you’re comfortable saying “no,” narrowing scope, and iterating fast.
• A builder of high-performing, inclusive teams. You’ve hired and developed diverse engineering teams, grown new leaders, and created cultures where people do the best work of their careers while feeling respected and included.
• An exceptional collaborator and communicator. You translate complex AI/ML and systems topics into clear narratives for non-technical partners; you influence peers and executives, drive alignment across Product, Engineering, Data, and GTM, and model Klaviyo’s values in how you work.
• Adaptable and resilient. You stay close to the work, dive deep when needed, and lead your teams through ambiguity and change with clarity and calm.
• A practitioner of AI-first ways of working. You know how to lead your whole team to use AI in day-to-day engineering development cycles, and you’ve experimented with or practiced fully agentic coding workflows.
• 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.

Nice to Haves

• Experience building AI-powered products for end users in complex SaaS workflows (e.g., martech, CRM, growth tooling, developer platforms).
• Prior work on agentic or copilot-style experiences embedded in production products at scale.
• Background combining experimentation platforms, offline evaluation, and human review loops to improve AI systems over time.
• Experience operating in multi-product, multi-team environments where clear interfaces and ownership boundaries are critical.
• Comfort working from our Boston hub with distributed teams across time zones.

Why This Role Matters

AI will reshape how businesses plan, execute, and optimize across every workflow — and Klaviyo is investing to make those capabilities real, safe, and accessible to every customer, not just the most technical ones. As Director, Engineering – AI, you’ll define and deliver the next generation of AI-native experiences in our core product, shaping both how our customers work and how our teams build. You’ll help ensure Klaviyo stays ahead in AI while staying true to our values: putting customers first, moving fast without shortcuts, and staying hungry and humble as we scale.

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

#IndeedRD

Klaviyo’s mission is to help businesses own their growth. As the Director, Engineering - Growth & Engagement, you will lead a portfolio of product engineering teams that sit directly on the customer journey: how customers are acquired, how they get to value, and how they experience Klaviyo-powered commerce on site.

This role will lead three teams with distinct but connected charters. K-Social turns social conversations, content, and engagement into structured, actionable data that enriches the Klaviyo profile and unlocks new marketing value. Growth owns onboarding, activation from free to paid, and cross-sell across our product-led growth motion. Customer Hub powers a personalized onsite account experience that brings together merchandising, support, offers, and self-service in one seamless destination.

You’ll lead an org of roughly 30+ engineers across these areas, including multiple people leaders, and partner closely with Product, Design, Data, GTM, and Support. This is a Director-level role for a product-minded, AI-first engineering leader who can connect strategy to execution, build a strong experimentation culture, and raise the bar on customer-facing product quality. 

What You’ll Do

• Own the engineering strategy, execution, and operating cadence across K-Social, Growth, and Customer Hub, ensuring each team’s roadmap ladders into Klaviyo’s broader growth strategy.
• Lead the engineering evolution of K-Social, connecting social engagement to the Klaviyo customer profile and building the technical foundation for products like Social Auto-Replies, engagement intelligence, retargeting ads, and content activation.
• Drive the Growth portfolio across onboarding, free-to-paid activation, and cross-sell, building systems and team habits that improve conversion, shorten time-to-value, and create measurable business impact.
• Shape Customer Hub into a best-in-class personalized onsite experience that encourages signed-in shopping, delivers proactive support, surfaces recommendations and offers, and makes self-service account management intuitive and useful.
• Build a high-velocity experimentation culture across the portfolio, including the instrumentation, frameworks, and decision-making rigor needed to run rapid tests and learn quickly.
• Partner deeply with Product, Design, Data, Marketing, Support, and other engineering leaders to turn ambiguous opportunities into clear priorities, scoped plans, and shipped outcomes.
• Raise the bar on frontend quality, product polish, performance, and reliability across customer-facing surfaces so teams can move fast without compromising craft.
• Balance near-term delivery with longer-term investments in experimentation infrastructure, identity/profile foundations, personalization capabilities, and product architecture.
• Define and operate against a clear scorecard for the portfolio, with metrics such as social profile capture, activation rate, free-to-paid conversion, experiment velocity, cross-sell attach, signed-in engagement, self-service completion, and product adoption.
• Build and develop a strong leadership bench by coaching managers and senior engineers, clarifying ownership, and creating an inclusive environment where teams can do the best work of their careers.
• Bring an AI-first mindset to both the product and the organization, identifying where AI can improve personalization, accelerate experimentation, strengthen support experiences, and help teams make better decisions faster.
• Continuously experiment with AI tools—testing, learning, and sharing insights to keep the team and organization ahead of the curve, as well as championing new applications that accelerate workflows and elevate quality responsibly.

Who You Are

• You have 10+ years of experience in software engineering, including significant experience leading multiple product engineering teams in a high-growth SaaS environment.
• You have experience managing managers and senior engineers, and you know how to scale your impact through clear expectations, healthy operating systems, and strong leadership talent.
• You bring meaningful product-led growth (PLG) experience, including ownership of onboarding, activation, conversion, monetization, cross-sell, or adjacent growth motions.
• You have built or scaled strong experimentation practices, whether through formal experimentation platforms or highly effective lightweight frameworks, and you know how to use them to drive product and business outcomes.
• You are a product-minded engineering leader who connects technical choices to customer value, adoption, and revenue impact.
• You have strong product sense and experience leading customer-facing application teams where UX quality, time-to-value, and iteration speed mattered.
• You bring enough frontend fluency to credibly lead teams building highly interactive, personalized customer experiences, and you care about polish, usability, and performance.
• You are highly data-driven in how you operate. You know how to identify funnel friction, define success metrics, evaluate tradeoffs, and course-correct quickly.
• You work exceptionally well with Product, Design, Data, GTM, and Support partners, and you can create clarity across ambiguous, cross-functional spaces.
• You move with urgency and judgment, set a high bar for execution, and are comfortable making hard tradeoffs in service of outcomes.
• 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.
• You use AI tools to accelerate exploration, shorten iteration cycles, and bring sharper ideas to the table.
• You bring a practical point of view on where AI meaningfully improves customer-facing products and internal engineering workflows, and you know how to balance speed with privacy, safety, and human judgment.

Nice to Haves

• Experience in martech, ecommerce, personalization, customer data, identity, or profile-linked products.
• Experience integrating with social platforms or building products on top of external ecosystem APIs.
• Experience with signed-in customer experiences, self-service support flows, merchandising, or account-management surfaces.
• Experience in zero-to-one product areas alongside more mature, scaled product portfolios.
• Familiarity with experimentation platforms, growth analytics, or personalization systems at scale.

Why This Role Matters

This role sits at the intersection of three high-leverage growth surfaces for Klaviyo: turning social engagement into richer customer profiles, helping customers activate and expand through product-led growth, and creating a more personalized onsite experience that keeps brands connected to their customers. The right leader will help turn these into a more connected portfolio—one that compounds customer value, accelerates growth, and raises the quality of Klaviyo’s product experience.

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