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.
Location: Boston Hybrid (3 days/week in office)
Lead Software Engineer – Campaigns ConfigurationAt Klaviyo, we value the unique backgrounds, experiences and perspectives each Klaviyo (we call ourselves Klaviyos) brings to our workplace each and every day. We believe everyone deserves a fair shot at success and appreciate the experiences each person brings beyond the traditional job requirements. If you’re a close but not exact match with the description, we hope you’ll still consider applying. Want to learn more about life at Klaviyo? Visit careers.klaviyo.com to see how we empower creators to own their own destiny.
Why You Should Join the Campaigns Configuration TeamThe Campaigns Configuration team is building the foundation for how Klaviyo customers create, manage, schedule, and understand the performance of their marketing campaigns across channels. This team owns the core configuration and reporting experiences that power Klaviyo’s Campaigns product.
Campaigns are one of the most used parts of the Klaviyo application, relied on by hundreds of thousands of customers to send targeted messages (Email, SMS, Push Notifications, and more) that deepen their relationships with their own customers. By joining the Campaigns Configuration team, you will have a direct impact on over 170,000 brands that use Klaviyo every day.
The team owns an ambitious roadmap, including:
- A reimagined Campaigns experience built from the ground up
- A new Omnichannel Campaign experience allowing users to send campaigns on multiple channels
- Intelligent personalization and future channel expansion
- Refactoring Klaviyo’s system architecture through domain decomposition
- Re-architecting the Campaigns experience for performance, scalability, and reliability
As a Lead Software Engineer on this team, you’ll sit at the intersection of architecture, execution, and cross-team collaboration for one of Klaviyo’s flagship product areas.
About the RoleAs a Lead Software Engineer, you are the technical leader and primary interface between the Campaigns Configuration team and the broader engineering organization. You will:
- Provide technical oversight and direction across a portfolio of projects
- Shape and execute on the forward-looking architecture for multiple Campaigns domains
- Partner closely with the Engineering Manager, Product, and Design on strategy, planning, and execution
- Work through influence and delegation to help the team deliver reliably and at a high bar of quality
You’ll spend your time balancing hands-on work (design docs, reviews, complex implementation) with guiding the team toward solid technical decisions, especially at our largest scales (including Black Friday / Cyber Monday, when we help customers send billions of messages).
How You Will Make a Difference- Lead technical direction for Campaigns Configuration
- Provide technical oversight and direction for a portfolio of Campaigns projects, including new channels, personalization, and analytics.
- Formulate and drive a forward-looking technical vision that aligns with broader business and platform initiatives.
- Own architecture and domain evolution
- Be responsible for the technical and architectural evolution of multiple key Campaigns domains (e.g., configuration, scheduling, reporting).
- Drive domain decomposition, service boundaries, and data model design to improve scalability, performance, and operational excellence.
- Deliver high-quality, scalable features
- Lead the design and implementation of best-in-class web experiences using React and TypeScript, backed by REST and GraphQL APIs.
- Ensure backend systems are robust, observable, and performant, with an eye on peak traffic events.
Scrutinize and reduce technical ambiguity and risk for upcoming projects through design reviews, technical spikes, and clear decision records. - Create and improve engineering processes
- Work with the Engineering Manager to ensure team adherence to solid engineering practices (testing, observability, rollout strategies, incident response).
- Create, teach, and improve shared engineering processes and patterns that can be adopted by adjacent teams.
- Uplevel adjacent processes, technology, and people by sharing best practices and reusable solutions.
- Influence beyond your immediate team
- Act as the primary technical interface to other Campaigns and platform teams, ensuring cohesive end-to-end solutions.
- Regularly collaborate with technical leads in other areas to align on patterns, standards, and shared components.
- Mentor and grow others
- Guide other engineers through design feedback, pairing, and thoughtful code reviews.
- Help teammates break down complex initiatives into clear, incremental deliverables with predictable timelines.
- 7+ years of software engineering experience, including significant fullstack work
- Strong backend experience, with a track record of building and scaling services in production
Hands-on experience with: - Frontend: React, TypeScript, and modern state management patterns (e.g., Redux or equivalent)
- Backend: Python with Django, FastAPI (or equivalent web frameworks)
- APIs: RESTful and GraphQL APIs
- Data & performance: relational databases (e.g., MySQL/Postgres), query optimization, caching, and performance tuning
- Experience acting as a tech lead or lead engineer for a team or domain:
- You have driven technical vision and execution for a portfolio of projects.
- You’ve owned architecture in at least one significant product area.
- You’re comfortable saying “no” or “not yet” when it protects long-term health.
- Strong systems and product thinking:
- Skilled in system design, reusable component architecture, and scalable frontend platforms.
- Comfortable designing systems that operate reliably at large scale and high traffic.
- Able to translate product ideas into pragmatic, incremental technical plans.
- Collaborative and influential:
- You work through influence and delegation rather than just personal heroics.
- You communicate clearly with engineers, product managers, and designers.
- You proactively provide and receive feedback within your pillar and across teams.
- Growth-oriented:
- Proven track record delivering complex features in fast-paced, product-led environments.
You’ve experimented with AI tools in work or personal projects, and you’re eager to learn how they can improve developer and customer experiences.
Experience with marketing automation, messaging platforms, or analytics-heavy products is a plus, but not required.
Technologies We UseYou don’t need to know all of these on day one, but familiarity with several is helpful:
- Frontend: React, TypeScript, Redux
- Backend: Python, Django, FastAPI
- Data & messaging: MySQL, Redis, RabbitMQ, Pulsar
- APIs: GraphQL, REST
- Infrastructure: AWS, Terraform, Kubernetes
Massachusetts Applicants:
It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.
Our salary range reflects the cost of labor across various U.S. geographic markets. The range displayed below reflects the minimum and maximum target salaries for the position across all our US locations. The base salary offered for this position is determined by several factors, including the applicant’s job-related skills, relevant experience, education or training, and work location.
In addition to base salary, our total compensation package may include participation in the company’s annual cash bonus plan, variable compensation (OTE) for sales and customer success roles, equity, sign-on payments, and a comprehensive range of health, welfare, and wellbeing benefits based on eligibility.
Your recruiter can provide more details about the specific salary/OTE range for your preferred location during the hiring process.
Get to Know Klaviyo
We’re Klaviyo (pronounced clay-vee-oh). We empower creators to own their destiny by making first-party data accessible and actionable like never before. We see limitless potential for the technology we’re developing to nurture personalized experiences in ecommerce and beyond. To reach our goals, we need our own crew of remarkable creators—ambitious and collaborative teammates who stay focused on our north star: delighting our customers. If you’re ready to do the best work of your career, where you’ll be welcomed as your whole self from day one and supported with generous benefits, we hope you’ll join us.
AI fluency at Klaviyo includes responsible use of AI (including privacy, security, bias awareness, and human-in-the-loop). We provide accommodations as needed.
By participating in Klaviyo’s interview process, you acknowledge that you have read, understood, and will adhere to our Guidelines for using AI in the Klaviyo interview Process. For more information about how we process your personal data, see our Job Applicant Privacy Notice.
Klaviyo is committed to a policy of equal opportunity and non-discrimination. We do not discriminate on the basis of race, ethnicity, citizenship, national origin, color, religion or religious creed, age, sex (including pregnancy), gender identity, sexual orientation, physical or mental disability, veteran or active military status, marital status, criminal record, genetics, retaliation, sexual harassment or any other characteristic protected by applicable law.
Top Skills
Klaviyo Boston, Massachusetts, USA Office
We're in the heart of the Financial district with easy access to public transportation and a short walk from South Station. We also have hubs in Denver, London and Sydney.
Similar Jobs at Klaviyo
What you need to know about the Boston Tech Scene
Key Facts About Boston Tech
- Number of Tech Workers: 269,000; 9.4% of overall workforce (2024 CompTIA survey)
- Major Tech Employers: Thermo Fisher Scientific, Toast, Klaviyo, HubSpot, DraftKings
- Key Industries: Artificial intelligence, biotechnology, robotics, software, aerospace
- Funding Landscape: $15.7 billion in venture capital funding in 2024 (Pitchbook)
- Notable Investors: Summit Partners, Volition Capital, Bain Capital Ventures, MassVentures, Highland Capital Partners
- Research Centers and Universities: MIT, Harvard University, Boston College, Tufts University, Boston University, Northeastern University, Smithsonian Astrophysical Observatory, National Bureau of Economic Research, Broad Institute, Lowell Center for Space Science & Technology, National Emerging Infectious Diseases Laboratories
