Senior Software Engineer, Klaviyo

Full Stack, Frontend

$156.8-235.2k

React
AWS
Docker
Kubernetes
TypeScript
Redux
JavaScript
Python
Django
GraphQL
Kafka
Redis
Terraform
Sentry
MySQL
Cypress
Apollo
Playwright
Senior level
Boston

1+ day a week in office

Klaviyo

Intelligent marketing automation powered by customer data

Be an early applicant

Klaviyo

Intelligent marketing automation powered by customer data

1001+ employees

B2BMarketingContenteCommerce

Be an early applicant

$156.8-235.2k

React
AWS
Docker
Kubernetes
TypeScript
Redux
JavaScript
Python
Django
GraphQL
Kafka
Redis
Terraform
Sentry
MySQL
Cypress
Apollo
Playwright
Senior level
Boston

1+ day a week in office

1001+ employees

B2BMarketingContenteCommerce

Company mission

To give online brands direct ownership of their consumer data and interactions, empowering them to turn transactions with customers into long-term relationships—at scale.

Role

Who you are

  • Experienced Frontend Leader: You bring extensive professional experience in leading frontend development projects, with expert proficiency in React and other modern JavaScript frameworks
  • You have a strong grasp of state management libraries, caching strategies, RESTful APIs, Apollo GraphQL, and UI testing tools like Cypress, Puppeteer, or Playwright
  • Architecture and Design Acumen: Demonstrable ability to architect robust, scalable frontend systems
  • You can effectively break down and prioritize tasks, design reusable and modular components, and foresee potential challenges in large-scale implementations
  • You thrive in a collaborative environment, working very closely with our design and user research team to translate wireframes and designs into functional requirements
  • Customer-Oriented Developer: Committed to creating user-centric solutions, you’ll leverage our user research teams, A/B testing framework, and UX design principles to refine product features for maximum impact and usability
  • Eager Learner and Team Player: Your drive to stay ahead of technology trends is matched by your enthusiasm for sharing knowledge
  • You actively seek out opportunities to enhance both your technical and leadership skills within a dynamic team environment
  • Advocate for Quality and Precision: Known for a meticulous approach to development, you ensure that all features meet high standards of quality and performance before deployment
  • You lead by example in writing clean, testable, and efficient code
  • Mentorship and Guidance: While this is not a management role, you’ll have a track record in mentoring, you are adept at coaching less experienced engineers, providing them with career guidance and technical advice
  • You are a go-to person for code reviews, offering insightful and actionable feedback

What the job involves

  • At Klaviyo, stepping into a Senior Software Engineering role means immersing yourself in high-visibility, high-impact projects that resonate deeply with our users
  • In this role, you will be a key player on our team, directly shaping our product experience to ensure it is intuitive and engaging for a diverse customer base
  • You'll have the opportunity to work alongside a team of committed and skilled engineers who are not just passionate about technology but are pioneers in creating seamless user experiences
  • By joining us, you'll engage in meaningful work that directly enhances how businesses connect with their customers
  • Klaviyo is a place for growth and learning and you'll have ample opportunities to expand your technical and collaborative skills, owning major features from conception to deployment
  • Our environment promotes continuous learning, offering you the chance to enhance your expertise across various domains and technologies
  • Building User-Focused Features: Develop and maintain highly visible, user-facing features that enhance the intuitiveness and delightfulness of using Klaviyo
  • Use advanced frontend technologies to create scalable, efficient, and visually compelling user interfaces that directly address customer needs
  • Engineering Best Practices: Contribute significantly to the engineering culture at Klaviyo by establishing, documenting, and promoting best practices
  • Lead initiatives to introduce and standardize frontend frameworks and tools that increase development efficiency and maintainability
  • Web and Browser Performance Expertise: Ensure optimal performance of our web applications, focusing on enhancing responsiveness and efficient browser rendering to deliver a seamless user experience
  • You'll leverage tools like Sentry and browser devtools to monitor, debug, and address performance concerns
  • Team Collaboration and Mentorship: Engage actively in building a strong team environment centered on education and mentorship
  • Learn alongside your peers to continuously advance collective skills and enhance software quality

Our take

Klaviyo is a marketing firm helping growth-focused eCommerce brands drive more sales with super-targeted, highly relevant email, Facebook and Instagram marketing campaigns. From personalised newsletters to automated emails when customers abandon their shopping carts, the marketing automation platform makes it easy for businesses to capture, store, analyze, and predictively use their own data to drive measurable, high-value outcomes.

Klaviyo's CEO, Bialecki, believes that the main problem with e-mail marketing today is that there is a divide between two kinds of tools: analytics tools that help you understand what people are doing on a website, such as what products they are considering, and messaging tools that send them a marketing e-mail. Operating primarily within the retail and eCommerce industry, Klaviyo aims to solve this by offering a tool that brings together analytics and messaging. This allows companies to bring all of their first-party data into a single platform to get a deep understanding of their customers and then activate that data to deliver highly-targeted, personalised communications through email and SMS. In the process, Klaviyo's customers get a deep understanding of their consumers.

Klaviyo is a fast-growing company mainly due to its business model - the firm offers a concrete ROI for Klaviyo’s clients if the software persuades customers to make purchases by treating different types of customers differently. An IPO in 2023 has led to Klaviyo's release of Klaviyo AI, which empowers businesses to unlock revenue-driving opportunities and deliver exceptional customer experiences across channels. Still in its early days of public listing, it will be interesting to see how Klaviyo fares in the years to come.

Freddie headshot

Freddie

Company Specialist

Insights

Top investors

Some candidates hear
back within 2 weeks

46% female employees

4% employee growth in 12 months

Company

Employee endorsements

Opportunities to learn

"Not only we have a good stipend to spend on learning but we also have development days every quarter, where we can switch off and focus on the areas..."

Funding (last 2 of 6 rounds)

Aug 2022

$100m

LATE VC

May 2021

$320m

SERIES D

Total funding: $778.5m

Company benefits

  • Private health care cover
  • All full time employees receive equity
  • Commuting allowance for when you do travel to the office,
  • A very generous education allowance every year for you to spend on learning and development.
  • Free books policy - if you’re better off for having read it (or listened to it—audiobooks are covered too!) we’ll pay for it.
  • Generous and flexible PTO policy
  • Participation in Klaviyo ESPP

Company values

  • We always put our customers first.
  • We are owners.
  • We strive to make the world more equitable.
  • We are ambitious.
  • We are always learning.
  • We collaborate radically.
  • We are remarkable.

Company HQ

Financial District, Boston, MA

Leadership

Previously CTO at RockTech, Senior Engineer at Performable, Lead Engineer at Applied Predictive Technologies and an SDET Intern at Microsoft

Ed Hallen

(Chief Product Officer)

Currently an Advisor at Team Engine. Previously worked in Enterprise Business Development at Google, Summer Associate at Accel-KKR and Principal at Applied Predictive Technologies.

Salary benchmarks

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Diversity & Inclusion at Klaviyo

Katelyn Nnake headshot

Katelyn Nnake (Director of Diversity, Equity & Inclusion)

  • At Klaviyo one of our key values is "we strive to make the world more equitable"
  • In 2023 over 75% of Klaviyos participated in a Klaviyo Resource Group

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